GeoTalks Express – Session 12 Questions & Answers

The twelfth of Blue Marble’s GeoTalks Express online webinar series entitled Global Mapper Tips and Tricks – Part II, was conducted on August 19th, 2020. During the live session, numerous questions were submitted to the presenters. The following is a list of these questions and the answers provided by Blue Marble’s technical support team.

 

How do you get the different binning method options (like variance) in the grid creation options?

The additional binning method options, Binning (Variance) and Binning (Median Value), in the Elevation Grid Creation tool will be available in the Global Mapper  Lidar Module version 22.0, which is being released later this year. 

 

I notice your current windows “order of presentation” seems reversed from my own experience. I experience the first loaded being placed “under” the next loaded data.

You can reverse the order of presentation for the layers in the Control Center with a right-click option. Right-click on Current Workspace the Control Center and select the option to Display Layer List In Reverse Order (Last is Drawn First).

 

When you feather elevation data can you then export the new feathered DEM?

Yes, Global Mapper will export the data that is displayed including any feathering settings for image or elevation layers. To capture these display settings involving multiple layers be sure to export all elevation layers involved. 

 

Is it possible to make a vector data transparent in Global Mapper?

You can completely hide a vector layer of features by unchecking the layer in the control center. There are some Null or No Symbol vector feature styles you can set to use for a layer or specific features. This will keep the features in the workspace and technically displayed, but they will not have a visible symbol used to display them. 

 

Can I export .shp data to .kml file complete with text display and full attribute data?

Yes, you can export vector features with attributes to KML/KMZ format. When exporting to this format be sure to choose the second Feature Descriptions option for Feature Description, Links, and Attribute Values. This KML/KMZ export option will be sure to export the attributes associated with each feature. 

 

Does Global Mapper have a function to create TIN? 

You can generate a gridded TIN and a vector TIN layer with the Elevation Grid Creation tool using 3D vector source data. When setting up the Grid Creation Options choose the Grid Method as Triangulation (Grid TIN of Points) to generate the gridded TIN layer. If you would like to also save the vector TIN, check the option to Save Triangulation Network (TIN) as a Vector Layer

 

Can these webinars be downloaded and saved to a pc or are they only available for review on YouTube?

Currently, the recorded webinar sessions are available on Blue Marble’s YouTube Channel. As a registered attendee, you will receive an email granting access to all of the GeoTalks Express session recordings. 

 

What happens when the attributes are null or blank?

With the Info Tips, if a feature has no label the Info Tip will display the text <NO LABEL> in place of the feature label. 

If you have configured the Info Tips to display a custom string of attributes and a feature does not contain a value for one of the attributes, the Info Tip will not display a value, it will just show a blank space for that attribute value. 

 

Can you set up a hotkey to toggle info tips on and off?

Unfortunately at this time there is no shortcut to toggle the Info Tips on and off, and there is no option to create a custom shortcut for this function. 

What you can do is add a custom toolbar button and place it on an existing toolbar to more easily turn the Info Tips on and off without having to navigate the view menu. 

 

Can we see info tips for 3D Points in 3D Viewer?

The Info Tips popup does not appear in the 3D viewer, it is only displayed when working in the 2D view. You can select individual points or features with the digitizer in the 3D view to display label and feature type information for the feature, but it will not be the information set up for the Info Tips. 

 

Can we merge DEM at various pixel sizes?

To merge multiple elevation layers, export them to a new file. When exporting elevation layers you will have the option to set the sample spacing or pixel size for the exported file. By default, this will be set to an average of the loaded layers, but you can alter these values to your desired pixel size for the merged file. 

 

Can you burn a DEM, like you want to change the depth of the river?

If you have a 3D area feature representing the river area, you can create a section of elevation grid for the river area only. After creating this smaller elevation grid, display the layers together and export them or use Combine/Compare Terrain Layers to combine them into a new gridded elevation layer. 

Alternatively, you could generate points from your existing elevation grid using the Layer Menu option to Create Point Features at Elevation Grid Cell Centers, and then create a new elevation grid layer using the generated points and your 3D river feature. 

 

Will there be a webinar on the LIDAR module?

We have some existing videos and recorded webinars on the Lidar Module available here on our YouTube Channel including this GeoTalks Express session on why you may need the Lidar Module. I also recommend this playlist on Lidar Processing in Global Mapper with the Lidar Module

 

Will the “Info Tips” work for “View in Google Earth”?

The Zoom to View in Google Earth option opens Google Earth on your machine. Info Tips are a function of Global Mapper and therefore will not work in Google Earth. 

 

After you split the layers, can you reverse them back into one?

There is no undo function for splitting a layer into multiple layers. In Global Mapper you do have the ability to select and copy (ctrl + c) and paste (ctrl + v) features between layers or to a new layer. You can select all the features in the split layers to then copy and paste them into a single layer again. 

Another option would be to export multiple layers to a single file in order to create a new un-split version of the layer. Load the exported layer into Global Mapper to see all the features appear in a layer together again. 

 

Can you bring in the Google Earth image to Global Mapper?

If you are able to save an image from Google Earth in a supported format, you will be able to load that image into Global Mapper. For the image to automatically display in the correct location in Global Mapper it will need to be saved as a fully georeferenced from Google Earth.  You can also render high-resolution imagery similar to Google Earth using the Online Data function.

 

Do the Info Tips work on 2 dem files?

The Info Tips can be set to work on multiple elevation files. In the Configure Info Tips dialog check the option to Include Values from All Layers Under Cursor to display the Info Tip information for multiple overlapping layers at the cursor location. 

 

Can you produce volume info between 2 of these contours like a stage storage?

If you have the source elevation layer you would need to limit the elevation grid layer to only display elevations between the contours of interest and then calculate the pile volume for the area. 

To restrict the elevation grid layer elevations open the Layer Options and on the Alter Elevations Tab, set the Minimum and Maximum Valid Elevations to the contour intervals you are interested in. Be sure to check the box to Clamp Out of Bound Values to Valid Range so there are no holes in the altered elevation grid. 

Next, use the digitizer to select the contour that bounds the area you would like to measure (the lower elevation for a pile, the higher elevation for a depression), right-click, and select Analysis/Measurement > Pile Volume

If you do not have the source elevation grid and only have the contour lines, create an elevation grid from the desired contours, and then calculate a pile volume using the contour lines and generated elevation grid. 

 

What size would a PDF be like that one?

When exporting data to PDF or 3D PDF format you do have options to specify the page size and orientation for the generated PDF file. The file size of the generated PDF depends on the resolution and size of the data you are exporting to this format.  For the example used in the presentation, the file size was a little over 5MB.

 

Can we apply display transparency to Google Earth displays?

Altering the display of the Google Earth imagery would be done in Google Earth, not Global Mapper. 

You can export raster imagery with transparency applied from Global Mapper to KML/KMZ format and load that file into Google Earth. In the KML/KMZ Export Options be sure to select the Export Image Format as PNG to support the image transparency in Google Earth. 

 

​How do I import custom shaders I set up in previous version​s?

From the Shader Options in the Configuration dialog box, you can choose to Edit a custom shader. There you should be able to Save to Surfer CLR File. You can then share this file to another machine or user and they should be able to create a custom shader and choose to Initialize from Surfer CLR File

If you are working in the current version 21.1 of Global Mapper, you can use the Import/Export User Settings option to share shaders and other Global Mapper settings from one machine to another. 

GeoTalks Express – Session 8 Questions & Answers

The eighth of Blue Marble’s GeoTalks Express online webinar series entitled Got a drone, now what? An Introduction to Pixels to Points, was conducted on June 24th, 2020. During the live session, numerous questions were submitted to the presenters. The following is a list of these questions and the answers provided by Blue Marble’s technical support team.

 

Can you see the orthoimage in 3D?

The orthoimage generated by the Pixels to Points tool is a 2D image. The image will appear in the 3D view, but it will be flat and appear below loaded 3D data layers. 

 

Do you have to purchase the Global Mapper Lidar Module to work with the drone data?

The Lidar Module is an add-on to the Global Mapper program that includes point cloud editing, viewing, and processing tools as well as the Pixels to Points tool shown in this webinar. 

If you are interested in testing out the Global Mapper program and the Lidar Module, I encourage you to download Global Mapper from our website and activate a trial license.

 

Can you perform tree height: DSM-DTM?

In Global Mapper you can use the Combine/Compare Terrain Layers tool to subtract one layer from another, like DSM – DTM as you have noted, to find tree heights. This does require having both a DSM (Digital Surface Model) and DTM (Digital Terrain Model) created for an area. 

Going back a step, you can generate elevation grid layers, DSM and DTM, using the Elevation Grid Creation tool in Global Mapper with point cloud data. The Elevation Grid Creation tool supports multiple binning methods, one uses maximum values to generate a DSM and another uses minimum values to generate a DTM. 

One of the drawbacks to photogrammetrically derived point cloud layers, those created from 2D drone images, is that ground area underneath tree cover is not usually identified accurately. This is due to the fact that the images only show the treetops, and not the ground so the process cannot identify features and create points representing the ground. If you are looking to generate your own DTM layer modeling ground, I would recommend true lidar data. That being said, if your collected images allow for a good reconstruction of the tree canopy you can create a DSM from the generated point cloud and compare that to an existing DTM layer. 

 

​What are the recommended camera orientation and drone height above the surface?​

​The height and angle at which you fly your drone when collecting images depend on the goals for your data collection. ​For instance, if you are planning to map the ground in a wide-open area, you can fly back and forth over the area collecting images looking straight down at the area of interest. 

If you are looking for more detail on terrain features or features on the surface, you may want to fly at a lower height, still taking nadir or maybe slightly oblique images, flying back and forth over the area. Then, to increase the views you have on the features in the area, continue flying over the area in straight lines crossing your original flight lines perpendicularly. This will provide views of terrain features from additional angles. 

To model a specific feature or pile, capture oblique images of the feature as the drone flies in a circle around it. This will capture many angles of the same feature, but with more oblique images you may need to use the masking tool in Pixels to Points to crop out areas along the sky and horizon. 

 

Each image file has coordinates of presumably the center point of the image. Where do those coordinates come from? Is it a drone camera or control function?

The drone collected images load into Global Mapper as Picture Points. These are point features, represented with a camera icon, that appear at the location of the camera when the image was captured. These coordinates are recorded and attached to the image by the GPS enabled camera that captured the image. The coordinates along with other information about the camera and image are stored in the EXIF data for each image. 

 

Do you have to use control points or is this an optional step to improve accuracy?

You do not need to use control points when generating your outputs using the Pixels to Points tool. Including ground control points will help to improve the accuracy of the outputs as they are placed in 3D space. Without ground control points the outputs generated from the Pixels to Points tool will still be accurate to themselves. 

You can also choose to incorporate some control points after generating your outputs. You can rectify layers in x, y, z, or use the Lidar QC tool to vertically adjust your generated point cloud layer. 

 

Is there anything in GM documentation regarding camera types? ie. pinhole 1, 2, or 3, etc?

Yes, additional information on the Camera Type options can be found here in the Global Mapper knowledge base. The information on the Pinhole camera types is as follows: 

  • Pinhole – A classic Pinhole camera
  • Pinhole Radial 1 – A classic pinhole camera with a best-fit for radial distortion defined by 1 factor to remove distortion.
  • Pinhole Radial 3 – A classic pinhole camera with a best-fit for radial distortion by 3 factors to remove distortion.
  • Pinhole Brown 2 – A classic pinhole camera with a best-fit for radial distortion by 3 factors and tangential distortion by 2 factors.

 

Can low-res lidar be used to calibrate Pixels to Points projects?

While you cannot use an existing point cloud to calibrate or help generate a new point cloud in the Pixels to points process, you may be able to derive some control points from your existing point cloud that could be used in Pixels to Points. 

In the Lidar Module of Global Mapper, there is a Fit Point Clouds tool that can be used to adjust one point cloud to better fit another. After generating your new point cloud with Pixels to Points, you may be able to use the Fit Point Cloud tool to adjust the new point cloud based on your existing lidar point cloud layer. 

 

Do you have to identify the control point in each of the green-colored images?

Yes, you should identify each ground control point in each image that it appears. With a ground control point selected in the Pixels to Points dialog the green listed images are suggestions on where the ground control point is likely to appear based on the coordinates of the point and the calculated image coverages for each input image. 

 

Is there some automatic tool in order to make placing the control points easier?

Placing the ground control points in images through the Pixels to Point tool is a manual process. With a control point selected the Pixels to Points tool will list some of the input images in green to suggest where the selected control point may appear. This suggestion based on the coordinates of the control point and the image coverages helps to narrow down the images to look through when placing the control point. 

 

Do you have a documented workflow for the drone data processing?

There is a workflow outline as well as details on the various steps, settings, and options for the Pixels to Points tool here in the Global Mapper Knowledge Base

If you would like more guidance on using the Lidar Module we do offer Lidar Module training, as well as Global Mapper training. These training sessions have been moved to an online format and more information can be found here on our website.  

 

After tagging a GCP in one image, can Global Mapper estimate the location in the overlapping images so that the user only needs to refine the location and not place it in every single image?

Tagging a ground control point in an image in the Pixels to Points tool only places it in that one image. Placing the ground control points in images is a manual process that must be done for each image, no ground control points are placed automatically.

 

I have seen in some cases where users put white paint markings on the ground or use trig beacons as control points. Is this a normal standard? 

Yes, you can absolutely paint a control point on the ground in your study area or use a trig beacon or other feature. A ground control point should be a point on the ground that you can survey the location of and that can be easily and accurately identified in your drone-collected images. 

 

How critical are the ground controls points when you do a drone survey? In other words, can you trust the data collected without any control points?   

You do not need to use control points when generating your outputs using the Pixels to Points tool. Including ground control points will help to improve the accuracy of the outputs as they are placed in 3D space. Without ground control points, the outputs generated from the Pixels to Points tool will still be accurate to themselves.

You can also choose to incorporate some control points after generating your outputs. You can rectify layers in x, y, z, or use the Lidar QC tool to vertically adjust your generated point cloud layer. 

 

Are hills and mountains identified as ground?

Hills and mountains should be identified as ground as they are ground area. The automatic ground classification tool in the Lidar Module requires some user-entered parameters to help guide the tool to more accurately classify ground. A couple of these parameters are Maximum Height Delta, the approximate range in elevation for ground in the area, and Expected Terrain Slope, the maximum expected terrain slope in the area. Adjusting these parameters appropriately will help to better classify ground in areas of steeper slope and higher elevation such as hills and mountains. 

 

Is it possible to load the GPS data in a separate text file that is not in the EXIF? We currently use full-size airplanes with medium format cameras that record the EO data separately from the EXIF. 

Yes, you can load the image position information from an external text or CSV format file. With images loaded into the Pixels to Points dialog, select images and right-click in the Input Images box. Select to Load Image Positions from External File and point to the file containing the image positions. More information on this right-click option can be found here with information on the input Images section of the Pixels to Points tool. 

As long as your captured images meet the data recommendations and have sufficient overlap and clear features, you should be able to use them with the Pixels to Points tool. 

 

Is it possible to create a point cloud with ground control only and no camera GPS positions?

Yes, the Pixels to Points tool can create outputs using images that do not have camera coordinate information. These images cannot be loaded into the main view of Global Mapper and would need to be loaded directly into the Pixels to Points tool

 

By downsampling the quality of the images, will the resolution of the exported data will also change?

Reducing the image sizes will reduce their resolution thus resulting in a lower level of detail in the input images. This may cause the program to find fewer like features based on the recurring pixel patterns ultimately slightly reducing the density and resolution of the outputs. 

For the best possible outputs it is recommended to use the full image resolution, but depending on the image sizes, settings, and machine specifications, that is not always possible. If you do end up needing to reduce the image sizes, try to reduce them by the smallest factor possible with your data and your machine. 

 

Is it possible to import metadata for images such as External orientation file instead of EXIF?

Yes, you can load the image position information from an external text or CSV format file. With images loaded into the Pixels to Points dialog, select images and right-click in the Input Images box. Select to Load Image Positions from External File and point to the file containing the image positions. More information on this right-click option can be found here with information on the input Images section of the Pixels to Points tool.

 

Is there a way to incorporate existing point cloud/lidar data to help with the mesh process? 

While you cannot use an existing point cloud to help generate the mesh feature from the Pixels to Points tool, you can create a mesh from a selected point cloud. If you have multiple point clouds loaded and selected for an area, all selected points will be used to generate the 3D mesh feature. 

 

​Can you load a file of post-processed GPS coordinates and replace the GPS coordinate in each image?​ To use GM to process drone mapping data it needs the ability to improve the image geotag with post-processed coordinates. Is this possible?​

​Yes, you can load positions for images from an external text or CSV format file in the ​Pixels to Points tool dialog. This can be used to add positions to images without any or to update and replace the existing image positions. 

With images loaded into the Pixels to Points dialog, select images and right-click in the Input Images box. Select to Load Image Positions from External File and point to the file containing the image positions. More information on this right-click option can be found here with information on the input Images section of the Pixels to Points tool.

 

Can you use any camera with the ability to geotag images?

Yes, any image taken with a GPS enabled camera should load into Global Mapper as a picture point. While the Pixels to Points tool is geared toward drone collected imagery you may be able to use any images as long as they meet the data recommendations

 

Can you have more than one ground control point in an image?

Yes, if multiple ground control points appear in a single image you should place them in that image. To place each ground control point, select the point from the ground control point list and then click Add Control Point to Image, and place the control point. Select another control point from the ground control point list and complete the same steps to add that point to the image. 

 

The kml file generated by Global Mapper needs to have the code edited after export so that DJI drones can read them. Are there plans to change kmls to be compatible with DJI?

Yes, we do have an open issue on resolving the incompatibility of Global Mapper produced KML files with DJI systems. The fix for this issue is temporarily slated for the Global Mapper 22.0 release. 

 

Do photo locations and GCP’s need to be in WGS84 coordinates or can other coordinate systems be used?

The photo location coordinates are assumed to be GPS derived and therefore implicitly bound to WGS84. Do you have collected images that use a different coordinate system for the photo locations? If so, could you share a few sample images? This would allow us to look at the EXIF info and look into a way to load them using the correct coordinate reference system.

Ground control points can be in any supported coordinate system. When loading a layer of ground control points into the main view of the Global Mapper workspace, they will be treated as any other point layer and loaded using the projection specified in the file, or selected by the user if needed. When loading control points from a text file into the Pixels to Points tool, you will be met with the Generic Text File Load Options, and since text files do not contain projection information, you will be prompted to select the correct projection for the file. 

 

Is MGA2020 projection supported in the output coordinate system?

The MGA (Map Grid of Australia) is a supported projection in Global Mapper, and GDA 2020 (Australian Geodetic 2020) is a supported datum. The workspace projection set in Configuration > Projection will be the coordinate system used when exporting files from a workspace. 

 

You need a pretty robust PC to process this data!

To process many images at full resolution it will take a more powerful machine. System requirements and recommendations for Global Mapper and the Pixels to Points tool can be found here in the Global Mapper knowledge base

 

I’ve noticed that when selecting the GCP, it sometimes does not exactly select the center of the GCP, is that OKAY?

You should try to tag the ground control points as precisely as possible in the Pixels to Points tool. Zooming and panning in the image preview window will help to place them at the desired location in the images. When placing ground control points on an image, you may see the control points snap to the image pixel center.  

 

How did you generate the flight line?!?

The flight line is automatically generated by loading the picture points via the Pixels to Points tool dialog. To generate a flight line, open the Pixels to Points tool and load the images directly into this dialog with the option to Load Image File(s)… Once the images have loaded into the Input Images list, go to the Map Menu in the Pixels to Points tool and choose to Load Image(s) as Picture Point(s). This option will load a group of layers in the Global Mapper workspace containing all the picture points for the drone images as well as a Flight Line layer with the flight path. 

 

Can you use a Global Mapper script to automate the process of Pixels to Points transformation?

Global Mapper script does support the command GENERATE_POINT_CLOUD to set up and run the Pixels to Points process. Running the process through a script does not allow you to perform manual tasks like placing ground control points or masking sections of images. 

 

Any recommendations for good flight plan apps?

We don’t have any recommendations for flight plan apps as there are many out there. We generally suggest working with the one most compatible with your drone model. 

 

Will you be supporting the GLB file in your next version?

We do not have any current plans to include the GLB format for 3D objects. Supported 3D model formats are listed here in the Global Mapper knowledge base

 

Do you have to fly the second time to capture the sides of the buildings/house at an oblique angle instead of nadir?

 

The flight path of your drone and the images captured should be designed with your end goal in mind. If you are planning to more accurately model building features as well as ground area you may want to capture oblique images from many angles. Keep in mind that the Pixels to Points tool and the Structure from Motion process can only construct the area for which there are clear views from overlapping images. 

Check out this blog post with some more details on drone flight tips when collecting images for use in the Pixels to Points tool. 

 

How many GCPs do you need for a certain area of your flight?

Your ground control points should be evenly spread over the area of interest and each ground control point should appear in multiple images. There is no rule on how many ground control points you should have in a given area. More control points will improve accuracy to a point, but eventually, the addition of more control points will not result in much improvement in the outputs. 

 

So the data altitude is assumed to be in NAVD88 instead of NGVD29?

Global Mapper does not work with vertical reference systems or transform between them. The assumed vertical system for Pixels to Points is Ellipsoidal Height. 

 

If you have two sets of flight plans with different altitudes for the same area, will it distort the 3d model because they have different ground sample distance size?

If both flights use the same camera, the lighting in both image sets is similar and fairly even, and the images are clear, the results from using the two datasets from different heights should process together fine. 

 

Should I use a special application or program to create my flight plan and make it compatible with Global Mapper? I mean, does Global Mapper have an application to create the drones flight plan? 

Global Mapper cannot create flight plans that can be used by drones on flights. You will need to use another app to create and execute the flight. Global Mapper does support many file formats, so if you are able to save your flight line you can then import it into a Global Mapper instance as you work with your drone collected images. 

Additionally, you can recreate your flight from your collected drone images using the Pixels to Points tool. To generate a flight line, open the Pixels to Points tool and load the images directly into this dialog with the option to Load Image File(s)… Once the images have loaded into the Input Images list, go to the Map Menu in the Pixels to Points tool and choose to Load Image(s) as Picture Point(s). This option will load a group of layers in the Global Mapper workspace containing all the picture points for the drone images as well as a Flight Line layer with the flight path. 

 

Can Global Mapper do the corresponding coordinate system transformation: in this case, could Global Mapper transform UTM coordinates to the German Gauß-Krüger coordinates?

You can reproject data in Global Mapper by changing the workspace projection in Configuration > Projection. Both UTM and Gauss-Kruger are supported projections in Global Mapper. The workspace projection set in Configuration > Projection will be used when exporting layers from Global Mapper. 

 

How long does it take Global Mapper to process 200 photos, with its best performance? What must be the specifications of my computer to achieve this processing time?

The length of time it takes to process an image set through the Pixels to Points tool depends not only on the number of images and the machine specifications, but also the size of the images and the settings applied in the Pixels to Points tool. Machine recommendations and requirements for using Global Mapper and the Pixels to Points tool can be found here in the Global Mapper knowledge base

 

Can we do all this processing with an Unregistered copy as my Registered Version is at my workplace but I am working from home?

An unregistered version of Global Mapper does have limitations that will likely prevent you from being able to process images with the Pixels to Points tool. If you need help with a Global Mapper license please reach out to our licensing team at authorize@bluemarblegeo.com with your most recent order number.

 

Any particular drone which works better with the Global Mapper LiDAR module?

We don’t have any specific drone recommendations, but you can find some data collection recommendations for the Pixels to Points tool in the Global Mapper knowledge base. 

 

Can you use scripting for all these processes?

Global Mapper script does support the command GENERATE_POINT_CLOUD to set up and run the Pixels to Points process. Running the process through a script does not allow you to perform manual tasks like placing ground control points or masking sections of images. 

 

We are watching while flying our drone doing a mapping job. I’d love for you to email the PowerPoint later. We want to start using global mapper and LiDAR vs drone2map or pix4d. We just need to learn it. 

I am glad you are interested in using Global Mapper for your drone data processing! We have thorough documentation on the tool and options here in the Global Mapper knowledge base. Additionally, as a registered attendee you should receive an email within the next week with access to the recording of this webinar.

If you have any questions about using Global Mapper, the Lidar Module, or the Pixels to Points tool specifically, you can reach out to our technical support team at geohelp@bluemarblegeo.com. 

 

Can you export to google earth?

Yes, Global Mapper supports many file formats for both import and export including raster and vector KMZ/KML formats compatible with Google Earth. 

 

Is it required to have a base overall image pre-loaded or can you do this work with captured images only?

A base image is not required. In the example shown in the webinar, the imagery simply provided a visual reference for the project. You can absolutely view and process your drone collected images without any background data, only loading the images and the generated outputs from the Pixels to Points tool

 

If possible please provide the best image capture settings for the fly-over? Or a couple of scenarios? 

The flight plan to fly your drone when collecting images depends on the goals for your data collection. Keep in mind that the Pixels to Points tool and the Structure from Motion process can only construct the area for which there are clear views from overlapping images. For instance, if you are looking to map the ground in a wide-open area, you can fly back and forth over the area collecting nadir images of the area of interest.

If you are planning to gather more detail on terrain features or features on the surface, you may want to fly at a lower height, taking slightly oblique images, flying back and forth over the area. Then, to increase the views you have on the features in the area, continue flying over the area in straight lines crossing your original flight lines perpendicularly to capture additional angles of the features.

Check out this blog post with some more details on drone flight tips when collecting images, and the data collection recommendations for images with the Pixels to Points tool. 

 

I use Microdrones mdLidar 1000 which has a 5mp camera which is primarily for colorizing the lidar point cloud. Can I generate just an orthoimage without generating a point cloud or 3D mesh?

You can select to only output the orthoimage from the Pixels to Points tool. Since this image is generated from the point cloud, the point cloud will still be constructed in the processing, but only the selected output, the orthoimage, will be saved. 

 

Does your workflow optimally utilize highly accurate camera coordinates in lieu of the use of GCPs?

If you do not choose to use ground control points with the Pixels to Points tool the camera coordinates alone will be used as the positioning information when generating the output layers. Increased accuracy of the camera coordinates will result in more accurately positioned outputs from the tool. 

 

Can you build a model without any coordinates i.e. without GCP or camera coordinates?

Yes, the Pixels to Points tool can create outputs using images that do not have camera coordinate information. The collected images with no coordinates cannot be loaded into the main view of Global Mapper as picture points and will need to be loaded directly into the Pixels to Points tool. With no camera coordinates or ground control points, the outputs will be placed at the origin (lat/long 0,0) since the program will have no coordinate references for the data.

 

Can I enter camera coordinates via a list rather than through EXIF embedded coordinates?

Yes, you can load camera positions from an external file text or CSV format file. With images loaded into the Pixels to Points dialog, select images and right-click in the Input Images box. Select to Load Image Positions from External File and point to the file containing the image positions. More information on this right-click option can be found here with information on the Input Images section of the Pixels to Points tool. 

 

Where in the object space do you specify “ground height”?

The Use Relative Altitude Based on Ground Height parameter in the Pixels to Points tool allows you to specify a ground height for the first image. Other points will use the entered value to calculate the vertical component for the outputs. 

 

Are there Points to Pixels tutorials available?

There is a workflow outline as well as details on the various steps, settings, and options for the Pixels to Points tool here in the Global Mapper Knowledge Base.

If you would like more guidance on using the Lidar Module we do offer Lidar Module training, as well as Global Mapper training. These training sessions have been moved to an online format and more information can be found here on our website.

Additionally, as a registered attendee you should receive an email in the next week with access to the recording of this webinar. 

 

The accuracy improvement of using ground control vs NOT using… are we talking metres, decimetres, or even better improvement? Under what conditions would the use of ground control points lead to marginal improvements? 

The accuracy of the outputs generated without control points depends on the accuracy of the image positions. If the cameras are using RTK/PPK then the output model should already be in the decimeter accuracy range. If the camera collects less accurate GPS coordinates, then high accuracy ground control points can definitely increase the accuracy from a few meters to closer to the GCP accuracy, which is also likely in the decimeter range depending on how they were collected.

Generally, we do recommend the use of high accuracy ground control points, or at least points collected with the use of some GPS averaging, if the collected image positions are not highly accurate. 

 

Also, can we have access to some test data like this for self-training?

We do not currently have a Pixels to Points lesson in the Global Mapper self-training available on our website. If you are interested in further training on the Lidar Module and the Pixels to Points tool we do have some public training classes scheduled in the upcoming months. These classes have been moved to an online format and you can find out more about training here on our website

 

What about PPK data?

High accuracy image positions or ground control points collected with a PPK system can be used with Global Mapper and the Pixels to Points tool. Using higher accuracy position information will help to improve the accuracy of the Pixels to Points outputs. 

 

Do the help files (or some discussion on a web site) discuss parameters for when you might want to adjust settings – e.g. analysis method, checkboxes for higher quality/resampling?  I’m thinking similarly to suggesting using masks for sky, water, snow cover, etc.

The Pixels to Points tool documentation contains information about the tool in general as well as an outline of the steps to use the tool and specific information on the options and settings available. 

 

How would I know which camera type my drone camera fits?

I recommend researching your drone model and contacting the manufacturer for information on compatible camera models. 

 

I would also like some information about processing time – some reference points of number of images, processor speed, cores, etc.

The time it takes to process an image set with the Pixels to Points tool depends on the number of images, the image resolution, the settings selected in the Pixels to Points dialog, and the machine on which you are running the process. You can find some system requirements and recommendations for Global Mapper and the Pixels to Points tool specifically in the Global Mapper knowledge base. 

 

Can I add EXIF info to images from a separate exterior orientation file like the one created from Trimble Applanix IMU/GPS?

Yes, you can load image positions from an external text or CSV format file. While I am not familiar with the format file created by your specific GPS device, information on the options to image positions from an external file can be found here with other information on the Image Input list in the Pixels to Points tool. 

 

​How accurately does the GPS of the drone need to be? Most camera GPS is no better than 5m accuracy.  Should potential drone purchasers be looking for any particular standard of GPS capture?

While more accurate image position information will produce more accurate outputs from the Pixels to Points tool, the use of high accuracy ground control points can help to significantly boost the accuracy of the outputs when using less accurate image position coordinates.

 

Looks like Global Mapper is projecting the images on-the-fly. Is that true?

The quick individual orthoimages loaded into Global Mapper are being projected to fill the approximate image coverage areas calculated from the camera position and view parameters.

 

I tried this with our new DJI Mavic 2 Enterprise Dual drone and Global Mapper asked what the focal length was. I had no idea so the Pixels to Points tool never worked.

If some camera parameters, like focal length, cannot be read from the image EXIF information Global Mapper will ask for the missing information. To find this I suggest looking through documentation on your drone and camera model and reaching out to the manufacturer for the hardware specs. 

 

​Is there any limitation when loading images like size, resolution,…?

There is no limitation on the image size, file size, or image resolution ​in Global Mapper. When working with large high-resolution images you may run into some hardware limitations when you attempt to process the images in the Pixels to Points tool. The most common limitation users run into when processing large datasets is an insufficient amount of available memory on the machine. In this case, the solution would be to reduce the image size by a factor.

​System recommendations for using Global Mapper and the Pixels to Points tool can be found here. Keep in mind that these are recommendations, and having more available memory will be beneficial when processing larger images. ​

 

Sometimes the images do not have EXIF, how to add this information using a CSV file?

You can load the image position information from an external text or CSV format file. With images loaded into the Pixels to Points dialog, select images and right-click in the Input Images box. Select to Load Image Positions from External File and point to the file containing the image positions. More information on this right-click option can be found here with information on the input Images section of the Pixels to Points tool. 

 

My images were generated by a camera which is not in the list of cameras, what can I do?

What camera do you use for image collection? Typically the camera information can be read from the image EXIF information, if it is not you will be prompted to enter some parameters. If you can provide the camera model and specifications I would be happy to pass them along to our team to get the camera added to the Camera Model list in the Pixels to Points tool. 

 

Is the irregularity in the trees and vegetation due to the way the data was collected or as a result of the SfM?

Since the goal of this image set was to reconstruct the farmhouse area, the irregularities and distortion in the trees stem from a combination of the data collection and the Structure from Motion (SfM) process. 

The images are nadir images and the tree areas where distortion is seen are on the edges of the study area. Being toward the edge of the study area with top-down images means that there aren’t as many good overlapping views of the trees in the source images. 

Additionally, trees and vegetation areas are often difficult for the Structure from Motion process because the images are noisy making it hard for the program to identify the match points for reconstruction. 

 

Does Pixels to Points work on non-nadir pointing images?

Yes, you can use non-nadir images, like oblique images, with the Pixels to Points tool.

 

Can you add different columns to the Image list, i.e. Roll/Pitch/Yaw?

If the Roll/Pitch/Yaw information is stored in the EXIF info for an image, it should appear as attributes for the picture point when the image is loaded into the main view of Global Mapper. If this information is detected, it will be used when ortho-rectifying individual images

However, these additional view parameters, Roll/Pitch/Yaw, are not currently used when generating the Pixels to Points outputs and cannot be viewed in the Input Images list information. 

 

Is it best to maintain a constant AGL or constant altitude when collecting imagery?

It is recommended to keep a constant altitude and in general, when capturing nadir images, fly the drone as high as possible. 

 

What is the camera type for DJI Phantom 3 Pro?

If the camera model and information cannot be read from the EXIF information in your drone images, the Pixels to Points tool will prompt you to select the camera and enter some specific parameters. I recommend you refer to the manufacturer for the specific camera model information for your drone. 

 

Can Global Mapper create true, not distorted, orthophoto? 

The Pixels to Points tool can remove distortion from the orthoimage by using the generated 3D mesh when generating the orthoimage layer. To generate the best quality texture for the mesh, you should select the Quality setting of Highest in the Pixels to Points settings. This combination of checking the option to Generate Orthoimage from Mesh and using the Highest Quality setting will remove distortion when generating the orthoimage layer. 

You can also choose to individually ortho-rectify images through Pixels to Points. By checking the option to Ortho-rectify Each Image Individually in the Pixels to Points tool settings each image will be placed on the map. With this method, there will likely be some noticeable seams between the images. 

 

Can we apply this workflow to satellite images within RPCS?

No, stereo imagery is generally collected with satellites, and with the Pixels to Points tool, you need multiple images (at least a dozen) that have a 60% overlap.

 

Can Global Mapper create disparity maps for export?

By using Global Mapper script to run the Pixels to Points tool you can add additional command options. One of these advanced options will generate depth map images. These depth maps are equivalent to disparity maps for the Pixels to Points and Structure from Motion process.

 

I take 360° panoramics for radar coverage prediction, will Global Mapper be able to process the pans to make a screen profile looking at the horizon?

Unfortunately, the Pixels to Points tool does not support the use of panoramic images, so processing your images would likely fail. If you were to collect images of the area with an alternate camera, you could use the Pixels to Points tool to create some 3D outputs of the area in order to view and analyze the area and the horizon line. 

 

Can Pixels to Points work underwater (clear) if you mask out the land and add a few control points underwater?

We have not tested with an underwater set of images. If the water does not cause noise or distortion in the images, the Pixels to Points tool may be able to generate an output, but it is unknown. There are various factors concerning how light travels through water that are not accounted for in our algorithms. 

If you have a dataset of clear underwater images that you would be able to share with us for testing purposes, that would be appreciated as we do not currently have test data of that type.

 

Are there any plans to incorporate flight planning within Global Mapper?

Currently, Global Mapper cannot create flight plan features that can be used by drones on flights to capture images. This is something being considered by our development team.

 

Can I use a QC tool to create and RSME for a surface vs check shots? I have used the LiDAR QC tool to do this but I am hoping to do this with a grid.

​While the Lidar QC tool can only be used with point cloud data at this time, we do have an open ticket, #GM-6634, on adding ​a QC tool for gridded elevation data. I have added your request to this ticket that our development team is considering. 

In the meantime, you could create points at the elevation grid cell centers for your gridded elevation layer and then use the Lidar QC tool to compare your control points to the created points from the elevation grid. 

 

​Can a camera and lens calibration be interpreted in Global Mapper?

Currently, camera calibration is not ​calculated and used in the Pixels to Points tool process. There is an open issue on adding some camera calibration tool to the program. This ticket is #GM-9644 and I have added your request to this ticket. 

Geo-Challenge — June 2020 Answers

How Well Did You Do?

Name the Country? – Uruguay

 

Name the Island? – Kodiak Island

 

Name the Body of Water? – Gulf of Corinth

 

Name the Mountain Range? – Atlas Mountains

 

Name the Capital City? – Hanoi

GeoTalks Express – Session 7 Questions & Answers

The seventh of Blue Marble’s GeoTalks Express online webinar series entitled Using Lidar for Archaeological Research, was conducted on June 10th, 2020. During the live session, numerous questions were submitted to the presenter, Forrest Briggs from LiDARUSA. The following is a list of these questions and the answers.

 

What kind of ASPRS points do you use to build DTM with buildings?

Ground classified points for the surface (DSM) and first returns for the DTM.

 

For the aerial mission did you employ ground control points? If so, how many targets on a typical project?

LiDAR is an active sensor meaning each point already has an XYZ, Photogrammetry does not provide that natively meaning control points are required to determine the position of the data. We always recommend using control points for survey-grade or construction-grade accuracy projects, however, for more archeology projects, it is not necessary. We recommend control, but it’s not required. It depends on the project.

 

What about bidirectional nadir satellite imagery?

Satellite and UAV don’t go hand in hand. Geo-referenced data (lidar and/or imagery) can be used together regardless of the source.

 

How is the laser aligned to the photogrammetry? Do you combine the reconstruction data from the photogrammetry with the laser scan data?

All of the instruments are bore-sighted, calibrated, and then geo-referenced to a common coordinate system.

 

If you scan it for free who owns the data you collect?

We own the data, along with the sponsor of the project and normally the country or landowner.

 

Can this be used to get bathymetry in a shallow lake?

We don’t manufacture green laser systems for bathymetric surveys, they are one very expensive and have a very limited application. They work well in clear water, zero turbidity, and Secchi depth.

 

Are your drones equipped with PPK/RTK module or do you need a typical base/rover setup?

We utilize PPK systems for LiDAR systems, RTK is far too limiting for LiDAR projects, you will either need a local base station near the project or take advantage of satellite or CORS networks base stations or utilize the advanced PPP algorithms that are created during an extended static aliment.

 

For the post processing of the data, do you exclusively ues GM?

We utilize our propriety software to create and fuse the lidar data with the IMU and GNSS to create a las or laz file format, that is what you import into global mapper for classification and feature extraction.

 

How do you separate the data from the different channels? Are there distinctions in the wavelength?

It varies with the scanner. The LAS files allow for annotating every point per channel, which we do.

 

What would you say are the main advantages of Lidar against photogrammetry and vice-versa?

With lidar, you can get points on the ground in most cases whereas photogrammetry is a “first return” system (so tops of grass and trees). Lidar is also better at sharp linear features such as transmission lines and railroads. Water boundaries are much easier with lidar as well. It is not a matter of accuracy on a hard surface as you can always get a better camera for this. Images are easier for a normal person to interpret.

 

How long did it take to fly the Uxmal area and what was the point density?

The 25 acres was collected in a 12-minute flight with 20% battery left. We were using our Revolution 120 lidar system mounted to the V1 DJI M200.

 

Do channels equate to returns?

A channel typically refers to the laser number and orientation. Each laser or channel has either 2 or 3 returns depending on the system. For instance, a VLP-16 is a 16 channel system, capable of 2 returns per channel.

 

Are the flights automated or are you manually flying the drone?

Generally, flights are automated in fixed-wing mode, you can fly manually in a pinch.

 

Is the output proprietary or .las/.laz format?

We export into las / laz / e57 / txt / XYZ / and several other formats. The most common are las and laz.

 

Did you have to file a flight plan with the FAA to be able to fly this mission?

Generally speaking, no flight plan is required to fly a UAV in the USA.

 

How much detail can you get on vegetation?

Can you identify individual species? Generally, the detail on the trees would need to be combined with on our LiDAR systems that integrates a LiDAR and camera to ensure you were to determine leaf and color and design.

 

Do you encounter a lot of high/low noise with your systems and do you find the Global Mapper auto noise classifier is sufficient in cleaning the data or do you need to couple it with manual noise cleaning?

Yes, all lidar systems create noise, regardless of what presented data is shown in marketing material. We use the GM automatic feature for the majority but almost always you will need to clean the data using manual methods as well.

 

What kind of drone you used for the lidar survey?

We use lots of different drones, multirotor, RC helicopters, gasoline, battery-powered. Your application and budget will determine what type of drone to use.

 

For water applications, how deep does lidar penetrate below the water surface?

We do not offer bathymetric lidar.

 

Do you use full waveform?

All LiDAR is waveform but only a few companies actually store it in raw form (it’s expensive to store and process). Most systems store discrete returns, which has proven sufficient for 20 years. We offer both for some systems.

 

Can you tilt the equipment when flying it on a helicopter, for looking sideward?

We offer 360-degree lidar systems as well as nadir lidar systems. Yes, you can mount the lidar whichever way you want and we of course will provide our expertise to ensure you are satisfied with the end result.

 

Flying time is the one limitation, but the other one surely is the data volume. So what is the max storage capacity onboard?

Flight time is a function of the drone, we offer a long-range drone with a 2-hour flight time, the data volume is also not an issue we provide with the system and external drive that can store 14 hours of scan data. We started building lidar systems for mobile ground-based scanning and normal scanning days can easily reach 8-10 hours, we have carried that technology forward to our UAV LiDAR systems to ensure you can scan all day without stopping.

 

Has LiDAR been used to find things that are underground?

LiDAR does not penetrate the ground, you will need GPR for that type of work.

GeoTalks Express – Session 6 Questions & Answers

The sixth of Blue Marble’s GeoTalks Express online webinar series entitled What’s New in Geographic Calculator 2020, was conducted on May 27th, 2020. During the live session, numerous questions were submitted to the presenters. The following is a list of these questions and the answers provided by Blue Marble’s technical support team.

 

Does Geographic Calculator acknowledge the ~2m difference in WGS84 to NAD83 origins yet?

Yes, Geographic Calculator has non-zero-shift coordinate transformations available between NAD83 and WGS 84 for many areas of use.

 

Can we take a lidar dataset in a projection with elevations in NAVD88 using Geoid12A, can we strip off that Geoid and add in Geoid18 utilizing this tool?

Yes, a 2-step vertical transformation can be performed (NAVD88 to WGS 84 ellipsoidal height via Geoid 12A and then back to NAVD88 via Geoid 18).

 

Can you briefly explain the proper way to use time-dependent / Date conversation inputs?

Enter the source and target epoch for most time-dependent coordinate transformations. Enter the target epoch for both the source and target dates for 14-parameter transformations. This will perform a transformation between the target epoch and the reference epoch. Note that starting with Calculator 2020, the dates are not prefilled to encourage users to be thoughtful about date selection as time-dependent transformations become the norm.

 

I take it that the Point Database Best Fit employs methods of least squares?

Yes, the control points can be fit with affine, or 2nd-5th order polynomial functions.

 

Can you convert a LAS file in a US State Plane 83 grid coordinate system to a local ground-based system?

Yes, a fitted coordinate system can be derived from control points recorded in both coordinate systems with the Point Database Best Fit job.

 

Would this work with 3D formats too? Such as 3D shapefile or 3D DWG/DXF also with 3D LiDAR data?

For context, we were discussing vector file conversions when this question came in.  The answer is yes, all of the jobs in the Geographic Calculator use both 2D and 3D coordinate systems.  If you have a 3D shapefile or any type of file that supports heights, you can perform conversions on those.

 

Is it possible to explain Special Features DEM? If any DEM is in a different coordinate system, how can we convert that DEM into other coordinate system in Geographic Calculator?

DEM files convert just like any other file.  You set the horizontal and vertical coordinate systems and select the appropriate Geoid to get between those surfaces.  DEM files may either be written back out to a DEM format or to flat colorized raster images.

 

When can we perform coordinate transformations – between different data sets when they are opened by the  Global Mapper or on the final data processing step?

In Global Mapper, transformations are done on the fly when data is loaded, but this only affects the data inside the GM session and not the source files that are brought in.  To permanently transform the data you must also export the layers to new files.  The projection set for the workspace in Configuration>Projection will be used for those outputs.

 

Are the SWARM data used in the IGRF13 and WMM2020 models?

Yes, the European Space Agency’s SWARM satellites are used in both the IGRF13 and WMM2020 geomagnetic models.

 

Can GeoCalc be used to help establish an unknown coordinate system if the site location is known?

The Point Database Best Fit job allows you to derive a polynomial best fit coordinate system between a known and an unknown (local) coordinate system if you have control points recorded in both systems.

The Projection Recovery Tool (part of the Georeferencer) allows you to estimate a known coordinate system that fits data recorded in an unknown system from a set of reference points.

 

GM will do that quickly too – is there any difference in accuracy please     Geographic Calculator often has more coordinate transformation options than Global Mapper, depending on the source and target datums, and area of use? ie EN to lat long.

Geographic Calculator has more coordinate transformation options than Global Mapper, depending on the source and target datums, and area of use.

In the case of a projection change, Geographic Calculator generally uses the same formulas as Global Mapper; however, Geographic Calculator has additional specialized projections available.

 

Can Geographic Calculator import custom a geoid file?

Geographic Calculator supports 16 established grid-based transformation formats.  If your file were in another format that is one of the many formats supported by Global Mapper, a “Blue Marble Gridded Data” (BGD) file can be created there and then exported to Geographic Calculator. There are also eight additional vertical transformation methods including unit change, height/depth reversal, offset and slope, and US VDATUM.

 

Is the Geographic Calculator covered by the standard Global Mapper license?

Geographic Calculator and Global Mapper each require a separate license/subscription. This includes accessing GeoCalc Mode in Global Mapper.

 

Can you input files of many coordinate pairs for inverse calculation that outputs a file with the results or does it work only for single point pairs?

Yes, the Point Database Forward Inverse job allows you to perform Forward or Inverse calculations on tabular/spreadsheet data. Excel, ODS, text, and several other formats are supported.

 

Can I convert an ASCII table with single line vectors defined by coordinate pairs to a shapefile?

The Point Database jobs have the option to write output to a number of vector formats, including shapefile, where one pair of columns is selected for the vector geometry (and all columns in the table are saved as attributes). Therefore, this vector output would contain point features.

If you have multiple columns (coordinates) per row that represent the vertices of line features, the Multiple Conversion feature in the Point Database Conversion job allows for the conversion of these coordinate columns in a single process. Writing this out to an ASCII file, this text output can easily be loaded into Global Mapper as one line feature per row.

 

Seven parameter 3D transformations?

The Geographic Calculator Datasource contains many 7-parameter coordinate frame rotation and position vector rotation transformations (as well as 3-, 4-, 6-, 10-, and 14-parameter transformations, among others).

 

NAD83 vis NADCO has accuracy 0f 0.15.  What is the accuracy of the NADCON5 transform?

NADCON5 accuracy varies by region and also within the various combinations of shifts used.  Overall accuracy has been improved, but NADCON5 is now able to associate individual accuracies for a point, rather than publishing one loose statement for the entire coverage area.  We are still working on how to bring this reporting capability into Geographic Calculator.  Also note that NADCON5 and NADCON results are not intended to match.

 

How can I use this Geographic Calculator for Nigerian Survey?

The Geographic Calculator Datasource contains the following Nigeria-specific geodetic datum, coordinate systems, projections, and transformations:
Datum: Minna
Geodetic coordinate reference system: Minna
4 Transverse Mercator projections: Nigeria East/Mid/West-Belt and WGS 84 / TM 6 NE (offshore)
1 Vertical datum and coordinate reference system: Lagos 1955
15 Coordinate transformations from Minna to WGS 84 (11 Geocentric, 3 7-parameter position vector rotation, 1 multiple regression equation)

 

How can you help us to include NIGERIAN IMAGERY in Global Mapper?

If you have your own image data, Global Mapper supports a wide variety of formats. There is also a built-in link to the “World Imagery” dataset. Global Mapper supports the Nigeria-specific Minna geodetic coordinate system and the Minna to WGS 84 (2) [EPSG 1168] geocentric transformation. In GeoCalc Mode, access to all the coordinate systems and transformations in the answer to your previous question would also be available to you.

Geo-Challenge — May 2020 Answers

How Well Did You Do?

Name the River? – Rio Grande

 

Name the Capital City? – Tokyo

 

Name the Body of Water? – Bay of Biscay

 

Name the National Park? – Kruger National Park

 

Name the Country – Afghanistan

GeoTalks Express – Session 5 Questions & Answers

The fifth of Blue Marble’s GeoTalks Express online webinar series, entitled Get Outside with Global Mapper, was conducted on May 13th, 2020. During the live session, numerous questions were submitted to the presenters. The following is a list of these questions and the answers provided by Blue Marble’s technical support team.

The Global Mapper Mobile knowledge base links below are to the Android version of the help pages. Although the two versions of the app contain the same functions, an iOS-specific version of the knowledge base is available here.

 

I want to know if with my license desktop, I can register a Global Mapper Mobile Pro?

​Is it the same to register the desktop version and mobile version?​ I mean if I register in desktop, can I use the Pro version in Global Mapper Mobile?

The Global Mapper Mobile app is free to download and use, but to register the Pro Module for the app you need to purchase a license. The Global Mapper Mobile Pro license is separate from the Global Mapper desktop license. You can purchase a license here on the Blue Marble website, or by contacting the sales team at orders@bluemarblegeo.com.

 

When adding a point, is there an option that allows you to take and attach a picture right there in the same window?

After tapping to add a point feature, at the bottom of the New Feature screen use the small picture icon option in the bottom right corner to add a picture to the digitized point feature. 

 

Can you cover adding photos and if those photos can later be sent to a kmz file?

In Global Mapper Mobile you can add photos to a map. You can link a photo to a digitized or existing vector feature from the Feature Edit screen, or you can add a photo directly to the map and it will be added as a picture point at the geotagged location of the photo. Since the photos taken with a mobile device do not have full georeference information they are all added as file links. 

After exporting your map from Global Mapper Mobile and sharing it to your computer, bring the Global Mapper Mobile Package file (*.gmmp) into Global Mapper desktop. From here you will be able to export layers of vector features to KML/KMZ format in such a way that the photos linked to the features will be displayed in the feature info popups seen in Google Earth. 

 

It is hard to see the measure tool against the aerial background. Can the color of the tool be changed?

The line added when measuring is a black line highlighted in yellow. Is this the part of the tool you are having trouble seeing?

The crosshair symbol used by the measure tool is grey by default, but the color of this symbol can be changed in the App Configuration

 

Will GMM be suitable for Android, iOS and Surface?

Global Mapper Mobile is available in the Google Play Store and the iOS App Store making it suitable for Android and iOS devices. The Global Mapper Mobile application cannot be run on a Microsoft Surface computer as that device is a Windows-based laptop, not a mobile device like a tablet or phone. You can run the Global Mapper desktop program on a Microsoft Surface laptop. 

 

Can we see real time field data collection activities via Global Mapper Desktop?

Data collected in Global Mapper Mobile is stored in the map in Global Mapper Mobile and cannot be streamed to Global Mapper desktop. To transfer collected data you would need to export the map and share it to your computer to then open the file in Global Mapper desktop.

In Global Mapper desktop you can set up a direct connection to an external GPS device in order to collect field data tracks in Global Mapper desktop.

 

Can we use a tiff file in the Global Mapper Mobile app?

Global Mapper Mobile does not support the import or export of TIFF files. Without the Pro Module the app will load and export Global Mapper Mobile Package format (*.gmmp) files. With the Pro Module the app will also import GeoPDF files and GeoPackage files. 

You can load TIFF files into Global Mapper desktop, and from that program export the layer to Global Mapper Mobile Package format to share and load into Global Mapper Mobile. 

 

How well does the mobile app work on an iphone or will I need an ipad?

Global Mapper Mobile works on Android and iOS phones and tablets. The only difference using a tablet versus a phone would be the screen size on the device, the app will function the same on both devices. 

 

We will get to this later but what about rest services? 

With the Pro Module in Global Mapper Mobile you can add custom online sources. Esri RESTful/Google Maps Tiles, OSM, WMS, and WMTS types are all supported. There is currently no support for feature services in Global Mapper Mobile. You can access feature services in Global Mapper desktop and export the needed features to Global Mapper Mobile Package format (*.gmmp) to then work with in Global Mapper Mobile. 

 

Is it possible to add data on the Pro version of Global Mapper Mobile through a script?

Global Mapper Mobile does not support Global Mapper script like Global Mapper desktop. You can use Global Mapper script in Global Mapper desktop to add data to a workspace, and export data to Global Mapper Mobile Package format (*.gmmp). This file can then be transferred to your mobile device and loaded in Global Mapper Mobile. 

 

Can Global Mapper Mobile support Garmin GPS Devices?

If the Garmin GPS device can be paired to the mobile device with bluetooth, and Garmin supports the device in a Garmin GPS companion app, you should be able to use the external GPS for data collection with the Global Mapper Mobile app. 

General Information on using an External GPS with Global Mapper Mobile:

Using an external GPS device with Global Mapper Mobile would be using the GPS to replace the location services information for your phone/device. To use an external GPS device you will need a companion app for the GPS to receive the data stream and push the location information into Global Mapper Mobile. 

To set this up, first turn on and connect your GPS device using bluetooth and the companion app that will read the information from the GPS device. This companion app, typically made by the makers of the GPS device, should allow you to see when the external GPS is connected as this is not yet indicated in Global Mapper Mobile, but we are working on an interface to see this information right in the app. With the GPS device connected in this way, the external location data should replace the internal location data and be read into Global Mapper Mobile. 

 

How big are the files you send as Global Mapper Mobile Package (*.gmmp) files?

The file size of Global Mapper Mobile Package (*.gmmp) files depends on the data you are sending in this format. More layers, larger datasets, and higher resolution data will result in larger files. 

 

Is there any 3D functionality in Global Mapper Mobile as there is in Global Mapper desktop?

With Global Mapper Mobile being designed to work on smaller and less powerful mobile devices, there is no 3D view functionality. You can have 3D data, like elevation grid layers, loaded into the app via a Global Mapper Mobile Package (*.gmmp) file, but you will only be able to view the data in 2D. 

 

Can you navigate to a point like a forest inventory plot with this app?

With the Pro Module of Global Mapper Mobile the app can display the distance and bearing from the GPS location to a selected point feature. You can select a point feature with the digitizer tool, and enable the distance and bearing in the GPS section of the app configuration

 

Can you get data off of your MangoMap account into the Global Mapper Mobile app?

MangoMap does not yet support streaming data from a map as an online source so you are unable to stream data from a MangoMap to Global Mapper desktop or Global Mapper Mobile.

If you have the source data you used to create your MangoMap, or you are able to download data layers from your MangoMap account, you can open those layers in Global Mapper desktop and export them to a Global Mapper Mobile Package (*.gmmp) for use in Global Mapper Mobile. 

 

Can one edit a point or vertex position once clicked?

Yes, you can edit the location of a point feature or a feature vertex one the feature has been created. To do this, select the digitizer tool and tap on the feature you would like to edit, tap again on the feature to open the Edit Feature screen. Tap Vertices to see the coordinates of the vertices or the location of the point feature. Select a vertex entry by tapping on it, and tap on the digitizer tool in the bottom right corner to edit the coordinates of the selected vertex. 

 

Is the elevation value displayed at the crosshair derived from the DEM layers? Or perhaps from the street map?

The elevation value shown for the crosshair location when an elevation layer is displayed comes from the loaded elevation layer on the map. 

 

I just installed Global Mapper Mobile on my phone. I logged in and now it needs a registration code. Is that emailed?

The Global Mapper Mobile app is free to download and use, but to register the Pro Module for the app you need to purchase a license. The Global Mapper Mobile Pro license is separate from the Global Mapper desktop license. You can purchase a license here on the Blue Marble website, or by contacting the sales team at orders@bluemarblegeo.com.

To register the Pro Module on your device, you will need to login with your Blue Marble account and then enter the order number for your purchased Pro Module license. 

 

Does the Global Mapper desktop version matter when working with the Global Mapper Mobile? We are still on version 18.

While you can use the Global Mapper Mobile app with an older version of Global Mapper desktop, we highly recommend upgrading to the current release for both programs. Many updates in Global Mapper Mobile depend on how Global Mapper Mobile Package (*.gmmp) files are produced from Global Mapper desktop. Newer versions of the desktop program include updates related to the writing and loading of Global Mapper Mobile Package files, and using an older version of the program will limit the functionality of your GMMP files and the Global Mapper Mobile app.

 

Can I use feature templates without the Pro Module?

Yes, you can use feature templates as part of a Global Mapper Mobile Package (*.gmmp) without the Pro Module. You can create, manage, and add feature templates as layers in a workspace through the Configuration > Feature Template section of Global Mapper desktop. 

 

Using external GPS submeter accuracy is only available with the Pro Module?

Using an external GPS device with Global Mapper Mobile would be using the GPS to replace the location services information for your phone/device. To use an external GPS device you will need a companion app for the GPS to receive the data stream and push the location information into Global Mapper Mobile.

While you can set up an external GPS unit to work with Global Mapper Mobile without the Pro Module, the new Advanced GPS options coming in version 2.1 of the app, used to manage and monitor data from an external GPS, will not be available without a license for the Pro Module.    

 

Is there a list of GNSS pairable devices for GMM Pro 2.1?

We do not currently have a list of all pairable devices. If you have a specific unit you are wondering about, please let us know. 

 

Can the Global Mapper Mobile be used for traffic analysis?

Global Mapper Mobile is designed to take your data into the field and collect data as you wish. You can then export and bring the data back to Global Mapper desktop for further analysis. Depending on what types of data you are working with and the analysis you are looking to do, this app could be used for some traffic analysis. 

 

Can you use connected GPS accuracy augmentation tools (IE bad elf) to increase accuracy of points and other features logged within Global Mapper Mobile?

Using an external GPS device with Global Mapper Mobile would be using the GPS to replace the location services information for your phone/device. To use an external GPS device you will need a companion app for the GPS to receive the data stream and push the location information into Global Mapper Mobile. Do you know if Bad Elf produces a companion app for their devices? 

 

Is there a way to track the surveyor in Field, and also track the editing?

There is no edit tracking function in Global Mapper Mobile but you can use the Save As option to save interactions of your map as you edit it. 

 

Can you add data layers from online sources?

From the Main Menu in Global Mapper Mobile you can choose to Add Online Data Layer to stream data from Open Street Map. With the Pro Module of the app you gain access to additional built-in online sources, as well as the ability to add custom online sources and save data from online sources for offline use. 

 

What about local reference systems, like here we are working with DLT Dubai local reference EPGS:3997?

You can set the projection for your Global Mapper Mobile Package (*.gmmp) file in Global Mapper desktop. In the desktop program, set the workspace options in Configuration > Projection, and when you export your data to GMMP format select the option to Use Currently Selected Projection

With the Pro Module registered in Global Mapper Mobile, you can edit the projection parameters for a map in App Configuration

 

Is UTM available only in the Pro version?

No, you can set the projection for your Global Mapper Mobile Package (*.gmmp) file in Global Mapper desktop. In the desktop program, set the workspace options in Configuration > Projection, and when you export your data to GMMP format select the option to Use Currently Selected Projection

With the Pro Module registered in Global Mapper Mobile, you can edit the projection parameters for a map in the mobile app through App Configuration

 

Can you use pre-existing schemas from a database or layer as opposed to creating from scratch?

While you cannot create a Feature Template from an existing layer, once you have created a feature template you can save it to a template file that you can share and load into other installations of Global Mapper desktop. 

 

Can Global Mapper Mobile record tracks and routes?

Yes, Global Mapper Mobile can create point, line, or area features with the GPS methods Time Interval and Distance Interval. These methods will record a vertex or point at a specified interval tracking the movement of the user with the device. The time interval and distance intervals can be set in the GPS section of the Global Mapper Mobile App Configuration

 

Can you customize data points (waypoints) with unique icons?

Yes, as you create features and see the Edit Feature or New Feature screen, you can tap on Type to set the feature type. Each feature type built into Global Mapper Mobile is associated with a feature style that will be used to display the point, line, or area feature on the map. 

 

Mobile works without an active cellular connection?

Yes, the GPS location services will still function on a device even if it is not connected to a network, wifi or cellular. You will need a cellular or wifi connection to share data to and from your mobile device and stream data from online sources. 

 

I need help opening maps using dropbox and iOS. Please run through the process, the map wants to open locally.

 

From the Global Mapper Mobile Open Map option, you can use the button in the bottom right corner to browse your device for a map. This browse screen will show files downloaded on your device as well as files accessed through a file-sharing app like Dropbox. 

When opening a map from a file-sharing app such as Dropbox, you will need to tap for more options in a file. In Dropbox select to Export the file and when options for export appear, scroll through the app suggestions and select Copy to Global Mapper Mobile. This should launch the Global Mapper Mobile app and open the map.

 

​Is there a benefit in tiling exports to GMMP?

Tiling your export to Global Mapper Mobile Package (*.gmmp) file will break the data up into separate GMMP files, one for each tile. Tiling your data could be useful if your data covers a large area. Users in the field will be able to load and work on smaller portions, individual tiles, of the complete data in Global Mapper Mobile. 

 

Highly recommend some plus and minus buttons for zoom. Especially when starting at world view and zooming. With finger pinch zooming I took a tour of Antarctica.

I have written a request ticket about adding zoom and pan buttons that you can enable in Global Mapper Mobile to assist with navigation around a map. 

From the control center in Global Mapper Mobile, use the home button to return to the full extent of the map, or you can tap on the options for a layer and zoom to a specific layer. 

 

Would you happen to know if this app will work with Trimble catalyst gps device?

We currently have an open enhancement request to be able to connect Trimble Catalyst systems with Global Mapper Mobile.

 

Can you use an external antenna for rtk Ntrip Network?

Currently Global Mapper Mobile does not support interaction with RTK based GPS devices. We have a feature request on this issue that our development team is considering.

GeoTalks Express – Session 4 Questions & Answers

The fourth of Blue Marble’s GeoTalks Express online webinar series entitled Ask the Experts was conducted on May 6th, 2020. This one-off event offered an opportunity for participants to submit questions, many of which were answered during the live session. Due to the volume of questions that were received, not all questions were answered during the webinar. The following is a list of all of the questions and the answers provided by Blue Marble’s technical support team.

 

Can you provide an overview of scripting? 

Global Mapper script is a very useful way to create and run a workflow through an open Global Mapper workspace, or without having to open the user interface. There is a scripting reference section in the Global Mapper knowledge base that you can find here (there is also a PDF version). 

 

Can we view more than one surface in the profiler?

Yes, if you have overlapping terrain surfaces loaded into Global Mapper, you can view both of these in the Path Profile tool by enabling the option to Draw Separate Line for Path from Each Terrain Layer in the path profile settings

 

How do I stop Global mapper from defaulting to meters when I load data? 

The units displayed for measurements can be set in Configuration. In Configuration > General > Measure/Units change the Distance Units setting to set the units for all horizontal digitizing and measuring tasks in Global Mapper. To set the vertical units to display, go to Configuration > Vertical Options and change the Elevation Display/Export Units setting. 

 

How can I make scripts or small programs that can perform inside the platform?

You can use a Global Mapper script to run some processes with source data or run them in a workspace using loaded data. Additional information on Global Mapper Scripting can be found in the scripting reference section of the Global Mapper knowledge (there is also a PDF version). 

 

How do you make different color dots? I can not seem to find the option to make various color dots, other than those existing. 

To make custom color dots for vector point features, go to the Point Styles tab of the vector layer options and when setting the style, select <CUSTOM_DOT_SHAPE> from the Select Point Symbol drop-down menu. You will then be prompted to enter the dot size and select the color for the point symbol. 

You can also add custom point symbols in Configuration > Styles > Custom Symbols. These will then display in the Select Point Symbol dropdown menu when setting the point style for your features. 

 

Is there a way to copy-paste path profile sections data from a table without having to export the file? 

Currently, there is no way to view the Path Profile sample information without exporting the path. From the File menu in the path profile dialog box, you can Save Profile Line(s) to New Layer and this will add a layer to the workspace containing the path profile line as a 3D line feature that you can work with in Global Mapper. 

I have written a request ticket (#GM-11003) about adding a way to view and copy the path profile samples from the Path Profile view without having to export the path. The Blue Marble development team will look into this request and I will let you know when I hear any updates on this matter. 

 

What is the best way to bring in elevation point data at 1 meter spaced points and then export it as 5 meter spaced points?

With your data loaded, you can create an elevation grid from your points. You can specify your desired spacing of 5 meters when generating the grid, or you can generate the grid at a finer resolution and downsample when exporting. Export the generated grid to a point format or text format, like XYZ grid, and specify a resolution of 5 meters in each direction to create a file with 5 meter spaced points.

 

Would you Classify each UAV LiDAR flight line point cloud before using the fit to cloud feature? 

The answer to your question is somewhat dependent on your data. If you can accurately classify the point clouds from the flight lines individually it may help to create a better fit between them using the Fit Point Cloud option to Only Match to Closest Points of the Same Class

If you are having trouble accurately classifying the point clouds individually you may want to fit the point clouds together and then classify them as one dataset. This may help with the classification of points along the edges of point clouds where flight lines overlap. 

 

I have a layer of points with an attribute consisting of a link to an image file. How can I activate the link to display the image?

If you have a file or image link in an attribute attached to a vector feature, use the Feature Info Tool to select the vector feature in Global Mapper. This should automatically open the linked file in your system’s default program for the linked file type, and/or display a dialog with a dropdown asking if you would like to see the feature information or open the linked file.

 

How do I take a list of coordinates and convert them?  Say i had point data that i want to convert from lat/long to UTM 27 – 10?

After you load your latitude/longitude data into Global Mapper, you can reproject it by changing the workspace projection in Configuration > Projection. UTM zone projections are supported in Global Mapper. After you have changed the workspace projection, export the data to your desired format. The data will be exported using the projection you set in Configuration > Projection. 

 

If I import shapefiles in Global Mapper having exported them from other software such as Model Maker, I lose text labels. 

How were your features labeled in Model Maker? Are the feature names contained in an attribute? To view attributes for a layer of features, right-click on the layer in the Control Center and select Edit Attributes

To set the labels for features in Global Mapper, open the Vector Options, and on the Labels tab, you will have some options on how to label the features. Make sure the box to Display Labels for this Layer is checked, and set your label preferences for the layer in this dialog. To use an attribute value for the feature labels, select the option to Use Selected Attribute Value, and select the desired attribute from the dropdown menu.

 

How can I use Google Earth coordinates in the View Shed tool easily without always pasting in Lat & Long?

In Global Mapper, if you have a point feature selected when you click on the map with the Viewshed tool, you will be asked if you would like to use the clicked location or the location of the selected point for the viewshed creation. In order to use coordinates from Google Earth, you can create placemark point features in Google Earth and save them to KML/KMZ format. You can then load the KML/KMZ file of point features into Global Mapper, select one or many, and use the viewshed tool choosing to use the selected point(s) for the viewshed creation.

 

Beyond current options, can the pointer info-tips be configured to present other spatial information?

Info Tips in Global Mapper can be configured to show the cursor location as well as a raster pixel values and/or specific attribute values from vector features.

 

Can you select an area in the 3D view and manually classify it? For example, can I select a tower and lines with a manually drawn box and classify it as power lines?

 

While Global Mapper does not currently support sweep selection in the 3D viewer, features can only be selected individually through this viewer, you can use the Path Profile tool to select and manually classify points from your point cloud. 

Using the Path Profile tool you can look at a cross-section of your point cloud and in this view, select and classify the points using the manual classification tools in the 2D map view or the Path Profile window. Points selected in the Path Profile view will also be selected in both the 2D main view and the 3D view in Global Mapper. Through the path profile menus, you are able to set the width of the profile with respect to lidar data to display a narrow or wider section of points in this cross-section view. 

Is there a way to convert GeoPDF files to GeoTiff files in a batch format? One of the issues I have had is getting my preferred layers on and hitting the ignore frames for each and every file. This dialogue box does not allow for the process to run in the background, you have to hit no about every 5 seconds.

You can use the Batch Convert/Reproject tool to convert Geospatial PDF files to GeoTIFF files, but this method does not provide any import options for the PDF files. 

When loading Geospatial PDF files into Global Mapper use the checkbox option to Use these options for all operations at the bottom of the PDF import options dialog to apply the selected layers to render and other load options to all PDF files you are loading. 

 

Is there a way to convert GeoPDF files to GeoTiff files in a batch format? 

You can use the Batch Convert/Reproject tool to convert Geospatial PDF files to GeoTIFF files, but this method does not provide any import options for the PDF files, but by default, multiple frames are ignored.

 

Can you help with ground/building extraction parameters in the Lidar Module? Large flat buildings are my foes. 

The parameters you use to classify your point cloud do vary based on your data and the characteristics of your study area. When classifying ground in Global Mapper be sure you are entering an accurate Maximum Building Width value as this will help to keep the tops of large flat buildings from being classified as ground.

Once ground points are accurately classified move on to the non-ground classification. Increasing the Max Co-Planar Angle Difference a bit may help to keep points from the tops of buildings being misclassified as vegetation.

Once your point classifications are accurate, the extraction of the features will yield much better results.

 

Is there any chance future versions of Global Mapper 64bit will offer the option to export gdb format?

In version 21.0 of Global Mapper, the ability to export vector features to a Geodatabase was added to the 64-bit version of the program. The 32-bit version of the Global Mapper can export raster layers to a Geodatabase if you have an ESRI license on your computer. 

 

Is it possible to do feature extractions, e.g., topographic lineaments?

Topographic features can be visually identified in an elevation grid layer of the ground surface. From an elevation grid, you can generate contour lines of the area to help identify and quantify the topographic changes associated with specific features. 

Using the Lidar Module, you can use the custom feature extraction tool in the Path Profile window. This function may allow you to manually extract lines for the edges of your features. 

 

Can Global Mapper perform a coarse cross-section analysis?

The Path Profile tool in Global Mapper allows you to view and analyze cross-sections of gridded elevation data and point clouds by drawing a line across your loaded data. In the settings for the path profile tool, you can adjust the sample spacing with respect to the terrain data. This allows you to look at a finer cross section line made up of more samples, or a coarser estimation based on fewer. 

 

What file formats can Global Mapper convert?

Global Mapper supports hundreds of formats for both import and export. A full list of the support file formats can be found here in the Global Mapper knowledge base

 

Are there workflow building tools available in Global Mapper similar to Model Builder in ArcGIS?

​Global Mapper supports many tools and processes through its command-based scripting. With Global Mapper script you can list commands for the Global Mapper program to run and execute these tasks through the Global Mapper user interface using loaded data, or by calling data in the script and running without using the interface of the program. 

Global Mapper script allows you to design a workflow and run it over your data automating some repetitive analysis tasks, similar to the Model Builder in ArcGIS.

 

How can I view/isolate individual features in a layer?

You can right-click on the layer in the Control Center and go to Edit Attributes. You can scroll down the Attribute Editor table and find the specific feature you are looking for. You can right-click on it to edit the feature and you can also see many other options in regards to the one feature. Use Ctrl+C or Ctrl+X to copy or cut the selected features and Ctrl+V to paste them to a new layer.

 

Can I run Global Mapper license server on AWS, So we do not have to use VPN to connect to the server?

While Global Mapper officially supports the tools on physical Windows machines, there are many users successfully running the tools on cloud servers. In these instances, it is important that the version of Windows you set up must have a stable machine ID and server name, as those are used in the license. You’ll also want to make sure the server is seen as part of your internal network. On AWS your security groups and firewall will need to allow access on two ports (both of which you can customize if necessary), and have exceptions for the few tools that run (lmgrd.exe, bmgeo.exe).

If you’re interested in testing this, I would recommend emailing the Blue Marble Sales Team (authorize@bluemarblegeo.com), explaining you’d like to test moving your license to a cloud server and provide them with the server machine ID and server name. They will then get you a temporary license with which you can test.

 

Is there a EPSG code for State Plane Alabama West NAD83 “Feet (US Survey)”. Only related codes found are 26730 and 26930, but not NAD83 Survey Feet.

When choosing your projection in Global Mapper, you can switch the Planar Units to FEET (US Survey). In the Configuration > Projection tab, choose State Plane Coordinate System under Projection dropdown. Then choose zone Alabama West. Then choose NAD 83 as your datum. Then under Planar Units, choose FEET (US Survey).

 

​When creating a grid for creating contours, at times I have to set it loose enough that it creates a grid and associated contours well outside of my desired area which then take much time to clean up. My question is, can I limit the area within which the grid, and then contours are created​?​

​There is a Grid Bounds tab in the Elevation Grid Creation Options window which allows you a few different options to constrain the grid creation. The contours then should be limited to the area that you have gridded.

What is the best way to smooth contours while losing the least accuracy​?​

Your best option would be to start in the Simplification tab and set the simplification to 0.00, all the way to the left. After the contours are created, you can manually adjust the smoothness of the contours, by selecting all features with the digitizer tool, then right-click in the main window, and go to Move/Reshape Features and pick SMOOTH.

 

“Is it possible to Remove the default Point, Area, Line Types from the configuration, We create our own set of types but all the other items interfere with workflow at times.”

Yes, this can be done by going to Configuration > Vector Display. Under ‘Filter’ you can choose Area, Lines, and Points as needed and filter out certain types. However, certain actions in Global Mapper utilize certain built-in types by default. I would recommend at least keeping “Unknown” points, lines, and polygons visible.

 

“Is it possible to manipulate the .dbf file (from your shapes) in Excel then convert it back to a workable dbf file in GM?”

This would be functionality independent of Global Mapper, or any other GIS which writes DBF files. Excel used to support the DBF format, allowing you to open and edit those files. However, I believe in the last few years, Excel has dropped that support. If you needed to edit attributes in a file, what you could do is open the Attribute Editor in Global Mapper and edit the data there directly. Alternatively, the Attribute Editor has a Save to CSV option so you could save that data to CSV, work with it in Excel, and then Join it back to the data in Global Mapper.

 

“Good morning, I want to ask how I can insert break lines (rivers and roads) when generating a MDT in Global Mapper, can this be done?”

Yes, when you’re using Create Elevation Grid this tool has an option “Use 3D Area Line Features as Breaklines”. If you have 3D vector features representing your roads and rivers, the elevation from those features will be included in your resulting terrain layer with that setting enabled.

 

“Is it possible to export vector objects created in the Lidar Module from a classified point cloud? You showed that feature in an earlier webinar.”

Yes, any features you Extract from a classified point cloud can be exported to a supported vector format. The features will be 3D by default so you may want to ensure whatever export format you use supports 3D features.

 

I can do most of my terrain analysis using Global Mapper except finding the shortest path on the terrain between two points.. Have you any plan to add this to the application?

Are you trying to find the shortest path using existing shapefiles on the screen in Global Mapper? Like a road network?  Or strictly just a terrain layer? If yes to my second question, you can simply use the Path Profile tool from the Analysis toolbar, to draw a path between the two points. You can also use the digitizer to draw a line feature between the two points, which should be your shortest path.

 

​Can I associate images to either points or lines in Global Mapper?​

Yes. After creating a point feature, in the Modify Feature Info window that appears, you can click Add File Link(s).. and this will relate it to file on your computer. When you use the Feature Info tool and select the Point feature, the image will open in whatever your default photo viewer is on your desktop. You can repeat this workflow with line features as well. 

In the case of photographs that are already geotagged, such as those taken with a GPS-enabled smartphone, the photos can simply be dragged and dropped unto the Global Mapper map window. A clickable picture point will be automatically created at the precise location at which the photo was taken.

 

How was the Pixels to Points algorithm developed? Was it licensed from somebody else? How does it compare with e.g. Pix4D?

Much of the tools under the hood of Pixels to Points come from openMVG and openMVS. More of this information can be found at our 3rd Party Library page on the User Guide. We do our own development as well to enhance the tool as we see fit from customer feedback and internal testing. 

It is a common question we get asked about comparisons to Pix4D or other software suites like that. Since the Pixels to Points tool is very new to the photogrammetry market, we do not expect all of the processing to meet exactly the same results, of more mature photogrammetric software out there, but many users are satisfied with the results that it creates. I would say we offer the full suite of GIS needs that can be done all in one program from processing your imagery, all the way to developing elevation grids, calculating pile volumes, creating contour maps. My suggestion would be to download a trial version of Global Mapper and test out the capabilities of the Pixels to Points tool against the others. Global Mapper pricing is not based on monthly subscriptions as with other software like Pix4D. With Global Mapper and the Lidar Module, you get a perpetual license that you can upgrade when you like.

 

How do you charge for training?

We have public training and custom training options available with some details described here on our website. For additional information on training curriculum and pricing please contact our training team at training@bluemarblegeo.com

 

I was trying to bring in elevation point data and chose the point option, but I wasn’t able to color classify the data once I had it in – I had to bring it in and choose the lidar data radial dial – is this because it was elevation data? That it wouldn’t classify as just plain point features? It was bathymetry data. 

While you can create an elevation grid from 3D point features, you must load the data as lidar to be handled like a point cloud in order to use the Lidar Module classification tools. 

The difference between loading as point versus lidar data when you import a text file is more about how Global Mapper stores and handles the data internally. When you choose the lidar option, the attribute structure and spatial indexing that are used are necessary for the point cloud classification tools. It’s also a storage structure that better handles visualization of large 3D point clouds. 

 

How can SPLIT function be used in generating map legend results?

Splitting layers in Global Mapper can help with data management and organization, and in a Map Layout  it allows for finer control over the entries displayed in the legend. In the Legend Properties in the Map Layout Editor, you can filter by layer what you would like to show in the legend.

 

​Could you tell me if you can add breaklines before generating the contour lines?

3D line and area features can be used as breaklines when generating an elevation grid. ​You can then create contour lines from your elevation surface that used the breaklines when it was generated. 

 

Are there ways or methods to do NDVI type analysis with SUAS collected RGB based imagery? I am trying to evaluate changing vegetation conditions over time through aerial photo monitoring and wondering about approaches to classify SFM derived orthomosaics to separate out vegetation changes and export as a new raster. Is there something that can be done with changing RGB bands or another approach? I have tried the raster to vector approach without success.

The formula for NDVI calculation is (Near Infrared – Red)/(Near Infrared + Red). If you have only RGB images of your study area you cannot calculate NDVI values as you are missing the Near Infrared (NIR) values. 

Creating 3D point clouds from your sets of drone collected images using the Pixels to Points tool in Global Mapper can allow you to track vegetation growth and expansion. Using the new Compare Clouds tool with point clouds generated from different image sets you can detect change in a vegetated area over time.

 

Can you give an overview of the Generate Watershed analysis with focus on the stream threshold, resolution and depression fill depth?

Details on all of the options for the Watershed Generation tool can be found here in the Global Mapper knowledge base

The resolution settings determine the resolution used to look at the terrain data in the watershed generation process. The default values should be the resolution, pixel size, values from the elevation data layer. Increasing these resolution values will lower the resolution used to look at the terrain decreasing the processing time but causing some loss of detail.

The stream threshold value determines the amount of water that must run through a cell in order for it to be considered part of a stream. Entering a larger value here will mean more water must flow through a cell for it to be considered a stream, resulting in only larger waterways in the output. Using a smaller stream threshold value will result in more minor waterways and streams in the output. 

The depression fill depth is used to determine the depth of depression in the terrain that is allowed to be filled and have water spill out of it and continue flowing. Depressions deeper that the entered fill depth will be considered basins and flow will terminate there. 

 

What are the best ground classification settings for steep terrain with tall, dense, evergreen trees? 

The parameters used in the automatic ground classification tool, and any other automatic analysis tool, depend on your particular dataset and study area. With an area of steep terrain, you will need to increase the Maximum Height Delta and Expected Terrain Slope values to better match the ground in the area. 

For an area that is densely forested, you will want to take a look at your data and make sure that you actually have points present that are from the true ground level. Depending on your dataset you may also be able to use some advanced filtering options from the automatic ground classification dialog to narrow down the points considered when trying to classify ground. 

 

​I know the pole classification, but my project needs to discriminate between medium voltage and low voltage poles. I have a post survey in a shapefile point file, how can I classify a lidar point cloud, from this survey?

If you do not have Medium Voltage and Low Voltage pole classes defined in Global Mapper, open the Filter Lidar tool and right-click on a class to change the class name and color as needed to create your new Medium and Low Voltage pole classifications. 

Before reclassifying your power pole point cloud points into Medium and Low Voltage pole classes, I recommend that you classify the point cloud including generic power pole classification. This will allow you to isolate and work with the generic pole classified points as you work to split them into the Medium and Low Voltage classes. ​​

With poles classified you can use the Filter Lidar tool to hide all points you are not interested in reclassifying, this would be all except the pole classified, Class 15 – Transmission Tower, points. Next, select the points you would like to reclassify as one of your pole subclasses and use the Change Lidar Class tool to reclassify these points. 

  • If your shapefile of vector features contains line features for each pole, you can use the Select Lidar by Distance tool to select the points for reclassification. 
  • If your shapefile of vector features contains area features, select the area features and use the Advanced Selection Option > Select All Point Features within the Selected Area(s) to select the points for reclassification. 
  • Or you can select points manually using the digitizer tool in the 2D map view or the Path Profile view, hold down the control key on your keyboard to select multiple areas of points. 

 

I was playing with the pole feature in a laz trying to get a single point, I think I got that working but then tried to apply it to a tree. I have been getting results showing several points created for a single tree and none are near what I would consider the center of the trunk.

The pole section of the automatic feature extraction tool is designed to extract pole features. In this tool there is a tree extraction section better suited to extract tree features from classified high vegetation points. 

 

Is it possible to create a watershed by clicking a ground point in a point cloud (or a pixel in a DTM)? The point selected should be the lowest point.

You can create and select a point feature representing the lowest point in your study area, and then use the Create Watershed Areas Showing Drainage to Selected Point(s) option in the Watershed Generation tool. This will generate a watershed showing the area that drains to the location of the selected point feature. 

 

Are there suggestions for processing/managing large lidar projects, like an entire US county scale?

To improve the load speed and draw time for a large dataset in Global Mapper, consider creating and loading your data through a map catalog

While there is no file size limit in the Global Mapper program, your computer has a memory capacity that you might reach when processing large datasets. Be sure that your machine is powerful enough to do what you are asking. When processing large datasets you may want to consider breaking the data set up into tiles and processing the data one section at a time. 

 

I want to know how and preferably how to automate the plotting a line to show the path an off contour bank or excavated ditch as it winds across a DEM landscape.  The line would typically have a grade/slope of 1 in 300 in most rural applications although In flatter landscapes 1 in 5,000 may be used. Urban sewers, as I recall, need a minimum of 1 in 50 grade. 

Various design constraints determine the starting point so the line may need to be either rising or falling from that point.

In the field, this is done by arcing a constant distance (radius) from each successive point and finding the desired height RL.

In my CAD program, I initiate a line and manually set each point by using the distance to last point display and mentally interpolating the height between adjacent contours.

I hope you can help.  I’m using Version 11 can v21 produce what I’m after?  

The Adjusting Line Elevations to a Slope function will take a digitized 3D line and adjust the elevations to a user-specified slope. Essentially, if you digitize a line on a DEM, select it with the digitizer tool, right-click and go to Move/Reshape Features, then click Adjust Elevations to a Single Slope, you will essentially be shifting that line to the new vertex elevation values. To visualize a trench, you could create a buffer around a selected line, then use the Calculate Flatten Site Plan option in the right digitizer menu to see the trench dug into the DEM.

 

Is it possible to analyze 3D data in Global Mapper such as Temperature or Salinity measured at different depths in the ocean?

Global Mapper can load and work with 3D data. You can take vector features representing your temperature and salinity readings and style them to create a thematic map. 

Global Mapper can also grid values. Typically this is used for elevation, but you can direct the program to grid values from another attribute by setting the elevation attribute on the Elevations tab of the vector options. Then use the Grid Creation tool to create a 3D raster gridded surface of these values.

 

I’d like to know the best workflow to export a raster file, tilling the image and doing the background transparency.

In any raster format export, you should see a Tiling tab in the Export Options dialog that will allow you to break the data being exported into tiles by one of a few options. 

Common raster formats like ECW, JPEG2000, GeoTIFF, and others can export images and make the background transparent through the use of an additional alpha channel for the image. To enable this option for background transparency, use the checkbox to Make Background (Void) Pixels Transparent in the file Export Options. 

 

How can I sort two shapes files with the same numbers but different positions, into one file of missing points?

In Global Mapper you can search for features with duplicate attribute values. Another option to find features that share some attribute values may be to search the vector features. After searching for features based on a query, you can delete, copy, or further manipulate the found attributes. 

 

How do I perform a complete terrain analysis and what are some lesser known capabilities which can be explored with Global Mapper?

Global Mapper contains many terrain analysis tools for you to use in a complete analysis. These include but are not limited to contour generation, volume measurements, and viewshed creation. Some lesser known tools would be Compare/Combine Terrain layers and Find Ridge Lines. These tools, along with many others, can be found in the Analysis Menu

 

What is the best way to load a subsea pipeline route comprising the end points, intersection points (IP) and the IP radi?

Global Mapper can load and edit vector features. With the points representing the pipeline selected you can use the digitizer right-click option Advanced Feature Creation > Create New Line Feature from Selected Points to connect the points into a line for the pipeline route. 

 

Can you make Global Mapper more compatible with ESRI’s ArcGIS?

Global Mapper supports many different file formats for import and export, and we try to make it as easy as possible to get data into our program. In version 21.0 of Global Mapper the ability to export vector features to a Geodatabase was added to the 64-bit version of the program. The 32-bit version of the Global Mapper can export raster layers to a Geodatabase if you have an ESRI license on the machine. 

You had asked for a general information update. The current release of Global Mapper is version 21.1 which can be downloaded from here. New features and changes to the Global Mapper program can be found in the What’s New section of the Global Mapper knowledge base

 

I would like to know what is the simplest methodology of the webinar.

This Ask the Experts webinar covered many different topics. If you are interested in a particular tool demonstrated in the webinar, you can find details on any function of Global Mapper in the program knowledge base

If you would like to watch the Ask the Experts webinar again, please fill out the form linked here to gain access to the recorded webinars from the GeoTalks Express series. We also have many other recorded webinars and helpful videos openly available for you on our YouTube channel

If you have any questions about the Global Mapper program, let us know in a reply to this email or by contacting our support team (geohelp@bluemarblegeo.com), or our sales team (orders@bluemarblegeo.com).

 

Using BMGC, can you create a local CRS using similarity transformation parameters instead of “fitted” CRS?

In Geographic Calculator you can define a new coordinate reference system and new transformations if you have the information to do so. If you cannot define a new CRS with the information you have, you can use control points to create a best fit coordinate system

 

I want to convert some shapefiles from one CRS to another,  is it possible in your software? Does your software include all the North America’s CRS specifically North Dakota (Williston basin)? Sometimes we use ND83-SF (SPCS North Dakota South / NAD83 / Feet), sometimes UTM83-13 (UTM 13N / NAD83) and in special cases we use SPCS27_250 (SPCS Montana Central / NAD27 / Feet).

These three projections are all supported in Global Mapper. You can select them in Configuration > Projection to reproject your data. 

For the State Plane Coordinate Systems, start by selecting SPCS from the projection dropdown, then select the zone and confirm the datum and units. For the UTM projection, select UTM from the projection dropdown, then the zone and datum. You can also load projection by using the Load from File option in Configuration > Projection and pointing to a *.prj file like the ones you shared.

 

I would like to know, what is the best method to export elevation grids and TIN surfaces into a regular meshes. 3D modeling software prefers this format for visualization and 3D printing purposes. Sometimes working with a triangulated TINN or irregular meshes create problems. If GM has a way to convert/export regular meshes it would be a great tool for 3D modeling, video games, and 3D printing fields.

Global Mapper includes a few different export options for 3D mesh formats. It can export FBX, Wavefront OBJ, just to name a few. I would take a look at this page that would give some more detailed information on the 3D export options: https://www.bluemarblegeo.com/knowledgebase/global-mapper-21-1/Export_3D_Format.htm?

 

I use the lidar module to extract trees on Maine woodlots and would like to hear how the various settings impact results.  Here are screen shots from a recent project where I extracted trees on a 30 acre woodlot.  I experimented with “resolution to extract” and found the .45 feet gave me the greatest number of trees.  Each lot is slightly different in this setting and falls in the range of 0.5 to 0.2 feet.

So, if you could go through the settings in these 2 dialog boxes and explain:  (1) what they do; and (2) how to find the sweet spot.

I’m using lidar data that I either acquire from NOAA or point clouds from maps built from drone acquired photography.

 As you have noted, the settings for classification and extraction will be a bit different for each point cloud depending on the characteristics of that point cloud and the terrain and features it represents. Finding the “sweet spot” for these parameters comes from a bit of trial and error as well as knowing your data and study area. I suggest you first focus on classification and fine tuning those parameters to classify the point cloud correctly before moving onto feature extraction. 

When working with drone image-derived point clouds you will want to make sure you have enough true ground points in vegetated areas to differentiate the ground level fro the vegetation. Since some of the parameters in the non-ground classification and extraction tools refer to height, you need to have ground classified points that can be used to determine the relative height of other points. 

With the Automatic Non-Ground Classification the Minimum Height Above Ground and the Minimum Vegetation distance are the more important parameters for high vegetation classification. The Minimum Height Above Ground sets a threshold for the start of the non-ground classification. This setting helps to week out other ground features like low vegetation, rocks, and cars. The Minimum Vegetation Distance sets a minimum distance between points for an area to be considered vegetation. This is useful as vegetation areas tend to have more spread out points compared to a more solid surface like a building.T he Maximum Co-Planar Distance and Co-Planar Angle Difference apply more to the building classification. Are you seeing your point classified correctly by this tool, or are there sections of points that remain unclassified or misclassified?

When extracting tree features the values you enter for the Minimum Tree Height, and the Maximum and Minimum Tree Spread help to guide the program to break the classified points up into individual tree features. The resolution at which to extract has to do with how finely the point cloud is looked at to extract features. Lower resolution point clouds should use higher values. 

 

I could certainly benefit from seeing a demonstration of the following, starting with a point or polygon “shapefile”:

1) How to embed a system URL pathname into a table field (such as within a shapefile field) to pop up a related Excel file or PDF.

2) How to edit a table value for the URL in case your “client” made a mistake in giving you the URL and now all the pathnames to a pop-up document are “wrong” and need to be fixed//edited.

3) Related Question: Can a shapefile have two table fields (i.e. more than one table field) set up for pop up of 2 separate documents related to one point or polygon?

Thank you for the questions. You can link external files to vector features in Global Mapper using some attributes. You would do this by specifying the path to the desired file to open in a FILE_LNK special attribute.

To add these attributes you can select a feature with the digitizer, right-click, and select Edit to open the Modify Feature Info dialog. Here you can click the button to Add File Link(s). You will then be prompted to select the file you would like to link to this feature. You can link multiple files to a feature. These additional links will be named FILE_LNK_1, FILE_LINK_2, and so on. 

You can also add or edit file links through the attribute editor. Right-click on a layer in the control center and select to Edit Attributes to bring up a table of attributes for the features in the layer. Here you can edit an attribute value by double-clicking on it, or add an attribute. 

To open a linked file, use the Feature Info tool and click on a vector feature. If there are files linked to the feature you will be met with a dialog asking you to select to open the linked file or display the feature attributes.

 

Volume Calculation question. For stockpile calculations in GM, how do you deal with removing conveyors, abutting piles, and other problems in order to obtain as good of data as possible from the point cloud?

Thanks for the question. When using the Pile Volume function in the digitizer, you will want to first constrain the area as best you can to the area you want to calculate. Since this function is used on an elevation grid type of raster, you would want to just digitize an area feature around the boundary of your stockpile to constrain the calculation to a specific pile. 

 

When georeferencing Ground Control Points in the Pixel to Points tool, the cursor “jumps” out of position. Why?

When placing ground control points on your images in the Pixels to Point dialog box, you should not see the cursor jumping out of position. Are you seeing it try and snap to the pixel centers or boundaries in the image? Are you seeing this at all zoom levels or only when zoomed in very closely to the image?

Please try downloading and installing the daily build of Global Mapper and testing your Pixels to Points workflow again. This build contains small updates to the program and will ensure you and I are comparing the same version of Global Mapper. 

Link to download the daily build: https://www.bluemarblegeo.com/products/global-mapper-daily-builds.php

 

When will Excel File data import come?

Currently, Global Mapper cannot import Excel files directly, you must save them as CSV files. There is an open ticket, #GM-4159, on adding the direct import of Excel format files to Global Mapper. Our development team is considering this ticket.

 

And related, is it possible to identify breaklines to constrain the contouring process?

You could use the option in the Analysis menu and go to find Ridgelines, which is currently our closest option. We do have an open enhancement request to automatically extract breaklines from terrain. This is ticket GM-6714. 

 

Is there any option on Global Mapper to draw the shortest path between two points on terrain, maintaining a specific slope cap?

In Global Mapper you can take an existing line feature and adjust the vertex elevations so it matches a user-specified slope. This Adjust Elevation to a Single Slope tool will not alter the x and y positions of the line vertices, but the z, elevation, values will be changed. 

There is a related open feature request on adding the ability to specify a start point, end point, and slope in order to generate a new line feature. This ticket is #GM-2599, and I have added your request for this feature. I will let you know when I hear any updates on this issue. 

 

Can you create a 3d line from x, y, inclination and azimuth?

The COGO digitizer tool in Global Mapper allows you to create a line feature by specifying a start point, bearing, and distance. You can also take an existing 3D line feature and adjust the vertex elevations so it matches a user-specified slope. This Adjust Elevation to a Single Slope tool will not alter the x and y positions of the line vertices, but the z, elevation, values will be changed. 

There is an open feature request on adding the ability to specify a slope value when creating a line feature. 

Geo-Challenge — April 2020 Answers

How Well Did You Do?

Name the Lake? – Lake Ontario

 

Name the Country? – Tunisia

 

Name the Capital City? – Havana

 

Name the Mountain? – Mount Vesuvius

 

Name the Island? – Isla Grande de Tierra del Fuego

GeoTalks Express – Session 3 Questions & Answers

The third of Blue Marble’s GeoTalks Express online webinar series, entitled So you think you know Global Mapper, was conducted on April 29th, 2020. During the live session, numerous questions were submitted to the presenters. The following is a list of these questions and the answers provided by Blue Marble’s technical support team.

 

Is there a tool for pan-sharpening?

Yes, Global Mapper has a tool for pan sharpening. The Pan-Sharpen Imagery tool can be found under the Analysis menu. Additional information on the pan-sharpen tool can be found here in the Global Mapper knowledge base

 

Can you import a line vector and generate the profiles?

Yes, you can select a vector line feature in Global Mapper and open a path profile along that line. The line does not need to be 3D as the path profile view will sample and display the elevation grid layer(s) along that line. 

To create a path profile from an existing line, select the line with the digitizer tool and then right-click in the main view of Global Mapper and choose Analysis/Measurement > Path Profile. 

 

​Do the images overlap?

When you have multiple image layers in Global Mapper that occupy some of the same area, they will overlap and the last drawn image will appear on top. You can change the draw order of layers in the Control Center by ​grabbing and dragging layers up and down the list. 

If you would like to blend the images together along the edges you may want to look into the Feathering options for the image layer appearing on top. Here you can feather out an edge of an image to help blend it into the underlying layer. 

 

​​Is there a way to show multiple surfaces in the 3D cutaway with the path profile tool?

​To view overlapping terrain layers in the 3D view you will need to ​enable the option to Draw Multiple Surfaces for Overlapping Terrain in Configuration > 3D View Properties. When you view a Path Profile cutaway in the 3D viewer multiple terrain surfaces will be displayed and cut away, but you will not see separate lines drawn on the cutaway face for the separate layers. 

​You can show multiple terrain layers the floating Path Profile window. To do this you will have to have multiple terrain layers loaded for an area, and you will have to enable a specific path profile setting. In the path profile settings, accessed from the Path Setup menu in the Path Profile view, check the option to Draw Separate Line for Path from Each Terrain Layer. 

 

​I​f you have two dates of elevation data would the two profiles show?

​You can show multiple terrain layers the floating Path Profile window if you have multiple to terrain layers loaded. To show multiple terrain layers in a Path Profile, enable the option to Draw Separate Line for Path from Each Terrain Layer in the path profile settings, accessed from the Path Setup menu in the Path Profile view.  

To view overlapping terrain layers in the 3D viewer you will need to enable the option to Draw Multiple Surfaces for Overlapping Terrain in Configuration > 3D View Properties

 

​​Has Global Mapper updated? I noticed you’re using v21.1​.

Version 21.1 of Global Mapper was released in February of 2020. ​You can download the new version of Global Mapper from the downloads page on our website. If your order is in current Maintenance and Support you are entitled to free version upgrades and should be able to license Global Mapper. If you are unsure about your Maintenance and Support status please contact our sales team, orders@bluemarblegeo.com, ​for further order assistance.

 

​​Does GM have the option to sunshade with a time/ date sun elevation for the location?

Currently, Global Mapper does not have an option to set the dynamic hill shade based on a date and time value. There is an open ticket on this issue, #GM-10988, that our development team is reviewing. 

 

​Using the dynamic hill shading is there a way to use the time of day to generate hill-shading?

Currently, Global Mapper does not have an option to set the dynamic hill shade based on a date and time value. There is an open ticket on this issue, #GM-10988, that our development team is reviewing. 

​Is there a modeling webinar using Global Mapper that you have available? 

We have recorded webinars available on our YouTube channel, BlueMarbleWebinars. What type of modeling information are you looking for? Here you can find a video on creating elevation grid layers from a 3D point cloud. 

 

Is there a way to take an average of those profiles?

In the Path Profile view, there is no way to create an average of the profile lines shown, but you can average the source elevation layers you have loaded. Using the Combine/Compare Terrain Layers tool in Global Mapper you can average the elevation values of loaded layers and generate a new layer. Then, when viewing your path profile this new average terrain layer should be drawn in the Path Profile. 

To show multiple terrain layers in a Path Profile, enable the option to Draw Separate Line for Path from Each Terrain Layer in the path profile settings, accessed from the Path Setup menu in the Path Profile view.

While you cannot take the average across all of the perpendicular path profiles, you can set an elevation corridor distance and display the average elevation along that corridor. In the Path Profile Settings under the Elevation Corridor section, set the type to Keep Average Elevation Along Perpendicular, and the Distance from Path to your desired perpendicular distance. This will show average elevation along the path filled in the path profile window, and a second line showing the elevation along the drawn path. 

 

Will Global Mapper work with underwater 3D models such as coral reefs?

G​lobal Mapper should display any loaded elevation layers or models, this includes layers describing underwater areas and reefs. 

 

​​So this tool creates the boundary of the lake without any input from the user?

The Create Areas from Equal Values tool takes input color values (RGB format) and generates area features by matching the color values in the image. In the lake example shown the lake was a distinct color from the surrounding ground area, so the tool was able to generate a feature bounding the lake based on the colors values in the image. 

 

Is the RBG value a number from 1 to 10 or so? 

RGB values are a color identifier commonly used to specify color values for pixels in images. An RGB value is three numbers representing the amount of Red, Green, and Blue in a specific color. The red, green, and blue values are on a scale from 0 to 255. 

 

How can you export in DWG all these profiles? Will it be one file with many profiles?

From the File menu of the Path Profile window you can select to Save Profile Line(s) to New Layer. When you select this option you can choose to then save All Cross Profiles. This will add 3D lines of the profiles to the main view of Global Mapper, you can then export this layer of features to any supported vector format. 

 

Can the axes in the 3D viewer be labeled with elevation, for the single terrain cutaway?

​Currently, in Global Mapper you cannot display the elevation values in 3D view, but the horizontal elevation guidelines are retained in the cutaway profile view. 

 

How do I alter the shader?

You can change the shader used for your elevation data with the Shader Drop-Down in the View toolbar. If you would like to alter the colors in a shader or create a completely new elevation shader, you can do so in Configuration > Shader Options

 

​​What happens if you choose a profile sampling distance smaller than the data resolution?

Since the source elevation data is a grid that is resampled to smooth between pixels, setting the path profile sampling distance to a value smaller than the source layer spacing will still result in a sampled path profile as you would expect. 

 

Can someone with the free version of acrobat still do some of the same interactions with pdf? 

Yes, you should still be able to view the PDF, toggle different layers on and off, and measure distances in Adobe Acrobat Reader. The layout is a bit different but you can find tools, like measure, on the Tools tab of the window. 

 

I am sorry if this is answered already, I’m having internet issues. Will this be available via recording?

Yes, all registered attendees to this webinar should receive an email in the next week or so with access to the recorded version of this webinar session. You can also register here to view recordings of past GeoTalks Express sessions. 

 

Can you feather grids like elevation data?

Yes, in the elevation layer options you will see the Feathering tab where you can set feathering options for your layer(s).

 

Can the 3D extruded features be color coded as well?

​Yes, the color styling options set in the Vector Options should be retained when you extrude the features using a selected attribute value. This allows you to create a both 3D by height, and 2D by color thematic map with your data. 

 

Does this 3D profile only work if you create the DEM in Global mapper? Can the elevation grid come from another software and saved that was saved as a .tif?

The Path Profile tool and the 3D path profile cutaway will work with any 3D elevation grid you have loaded into Global Mapper. This ogrid could be one created in the program or a grid loaded from a file, like an elevation TIFF. 

 

Can you then add lat and long to your job sites?

With the Find Address tool you can search for multiple addresses to find the positions (coordinates) for features or job sites. As demonstrated you can then create point features at those locations. 

 

Does this work with the perpendicular view you mentioned earlier?

​With a perpendicular path profile the 3D cutaway will not work directly from the path profile as you now have multiple path profile lines drawn. 

You can save the profile lines to a new layer from the File menu in the Path Profile window and then create new profiles from the saved lines one at a time viewing them in the 3D viewer with the cutaway option enabled. 

 

Can you automatically generate (or export) a series of profiles or profile data based on the streamflow lines generated in the Watershed tool? Or similarly a series of line features of any sort?

To create a Path Profile from an existing vector feature, select the feature with the digitizer, right-click in the main view and choose Analysis/Measurement > Path Profile. ​ Each profile will open in a separate tab of the Path Profile window and this option is limited to six-line features at a time. You can save or export a profile from the File menu in the Path Profile window. ​

 

​​Does the person opening the PDF need Adobe Acrobat Pro to turn on and off layers?

​No, you should still be able to view the PDF, toggle different layers on and off, and measure distances in the free Adobe Acrobat Reader. The layout is a bit different but you can find tools, like measure, on the tools tab of the window and the layers sidebar on the left of the main PDF view. 

 

Any way to save viewpoints in 3D view?

You can save an image of your data displayed in the 3D viewer by using the Save Image button (camera icon) in the 3D view window. This will capture the current view and save it to an image file format. 

 

Does the smooth function just smooth once from the original roughness or does the effect stack?

You can smooth features multiple times and the effects will stack on top of each other making the lines appear smoother each time you apply the tool.  

 

Can you feather along a partial length of an edge?

When specifying an edge of an image to feather along, you can only select the whole edge with the checkboxes available on the Feathering options tab of the Layer Options. 

That being said, there are some additional options in the feathering dialog to feather the data with respect to a selected polygon. Depending on what you are trying to achieve this option to use a polygon feature for the feathering bounds may work for you, although the data will be feathered along all sides of the selected polygon(s). 

 

Does the pdf contain the coordinate system for the geospatial tool? Does it do eastings and nothings too based on the projection in GM?

While the Geospatial PDF file will retain the workspace projection, as set in Configuration > Projection, if loaded back into Global Mapper or a GIS program, the coordinates displayed in Adobe will be shown in geographic latitude/longitude values. 

 

Are the profile axes visible in the 3D window?

Currently, in Global Mapper you cannot display the axis values in the 3D view for a path profile cutaway. However, the horizontal elevation guidelines are retained in the cutaway profile view to provide some reference.   

 

Can we use that tool with the coast line?

You can draw a path profile along the coastline and display it. You can also generate a path profile from an existing vector feature if you already have a line representing the coastline. Both of these methods allow you to enable the perpendicular path profiles option, which you can do in the path profile settings, before or after creating a path profile. 

 

Is it possible for the perpendicular path profiles to have varying widths, such as being constrained to a hydrographic feature polygon?

After creating the path profiles, you can use the Path Profile File menu option to save the profile lines to a layer in the Global Mapper workspace. This will save a layer with a 3D line for each profile. You can then crop these line features to a specific area like a hydrological feature.

 

​When demonstrating the Voronoi/Thiessen diagram with rainfall collection data, you suggested we use watershed/catch basins instead of doing the Voronoi/Thiessen analysis. While this is a great suggestion for an analysis and thematic mapping, it requires a different workflow. 

For your suggested workflow you would need not only the rainfall measure points, but also the watershed area features. You can generate watershed areas with an elevation grid and the Watershed Creation tool in Global Mapper. With the rainfall point data, and the watershed areas, you can copy attributes from nearby/overlapping features to apply the rainfall amounts from the point features to the watershed features. This would then allow you to generate a thematic map of the watershed areas based on the measured rainfall data.