Drone Flight Tips When Using Global Mapper’s Pixels to Points Tool

Written by: Mackenzie Mills,  Application Specialist

As drones gain popularity and more people begin collecting their own data for analysis, tools like Pixels to Points in Global Mapper become more important in workflows. The Pixels to Points tool is the structure from motion (SfM) process to create three-dimensional data and image outputs from sets of drone-collected images. In many situations, this is a great and cost-effective alternative to collecting lidar (light detection and ranging) data.

The SfM process used in the Pixels to Points tool identifies features in multiple images by matching pixel patterns in the images. Features identified in multiple images are then triangulated and constructed in 3D space to generate three-dimensional outputs, including a point cloud.

Whether you are experienced with drone data collection or are new to this method, it is worth learning or reviewing some tips for quality data collection. The most important requirements for drone-collected images that you intend to process with Pixels to Points (structure from motion) are overlap and clarity.

The overlap between collected images is very important as it allows the tool to identify features in multiple images in order to triangulate them in space and construct the output layers for the area. With sets of images that contain little to no overlap, the Pixels to Points tool cannot identify features from multiple views in order to triangulate and construct the outputs. This will result in an error, or outputs that contain missing data. We recommend a minimum of 60% overlap between adjacent images, but you should always plan for more.

Drone images of a baseball field.
Drone images of a baseball field being aligned.

The images you intend to use need to have clear and identifiable features so that the Pixels to Points tool can identify them based on clear pixel patterns. This means two things, (1) the images need to be in focus, and (2) the images need to have identifiable features. Images that are blurry due to the camera shaking or vibrating, or out of focus will yield incomplete or no results from the structure from motion process. This is because the noise(or movement that makes the images blurred) inhibits the program’s ability to identify features. Areas with no identifiable features will similarly result in errors. Common scenes that encounter this issue are areas of snow cover, all white with no features, or bodies of water with no lasting features that can be identified.

Comparison of a focused and a blurred image due to noise.
Comparison of a focused and a blurred image due to noise.

Depending on the goals of your project, you may want to use different methods for collecting images. Some basic variables that go into how you plan your drone flight are pattern, height, and angle.

Drone flight patterns.
Drone flight patterns.

For two-dimensional mapping to generate an elevation model of a ground area and not surface features, capturing nadir images (looking straight down) from as high up as possible is best. For this data collection, you can use a simple mow the lawn pattern moving back and forth over the area of interest.

For 3D modeling of high relief terrain, buildings, and structures, you’ll want to capture oblique images in order to capture the sides of features. Here you would fly at a lower height, 150 to 200 feet, with a front-facing camera and collect data in a checkerboard pattern, going back and forth over the study area, then back and forth again crossing over the previous flight lines. This will help to capture the sides of terrain features from various angles for a better three-dimensional reconstruction.

For structural modeling of a specific building or stockpile feature, you’ll want to capture oblique images as you fly at a lower height in a circle around the object of interest. This will capture images covering the sides of the feature to create a detailed model.

Types of angles of drone images.
Types of angles of drone images.

Flight planning is an important part of data collection when working with drone collected data. Understanding the variables and data requirements for the Pixels to Points tool and other SfM processes will help you to collect images better suited for processing. In turn, this will create higher quality results for further work.

GeoTalks Express – Session 1 Questions & Answers

The first in Blue Marble’s GeoTalks Express online webinar series, entitled Getting to Know Global Mapper, was conducted on April 1st 2020. During the live session, there were are number of questions submitted to the presenters. The following is a list of these questions and the answers provided by Blue Marble’s technical support team.

 

What is the spatial extent of the data being loaded? 

I believe that you were asking this question in reference to loading data from an online source. When loading online data you have a few options to choose the extent to load. The extent is specified in the connect to online data dialog and you can load data for only the current screen bounds, within a certain distance of an address or coordinate, within a selected area feature, or for the entire source bounds. In the session today I demonstrated loading only data for the current screen bounds. 

When loading data from an online source keep in mind that this data is streamed and relies on your network connection to load the data. Smaller areas of data will likely load faster.

 

How do you define the bin sizes in the depth example?

When setting up the point styles for the lake depth points I manually entered and set the style for each value using the New Value button on the Point Styles tab. 

You can use the Load Values option to automatically load values from a layer of features. You can load each unique value, or if the values are numeric Global Mapper will recognize this and give you the option to load only key values (minimum, average, average + two standard deviations, maximum) and then blend the colors between these values. 

 

How do you get contour lines? 

In Global Mapper contour lines are created from a loaded elevation grid layer using the generate contours tool. In this tool there are many options for generating contour lines including the option to set a specific contour interval in meters or feet. 

 

Is it possible to know the date from World Image Data?

Blue Marble does not create or update any of the data streamed from the online sources. For more information on any built-in online source, image or otherwise, you can right-click on the source name from the Online Sources dialog and select to Display Source Web Page/Terms of Service

 

Can Global Mapper produce contours from point data?

Contour lines need to be created from an elevation grid layer. You can generate an elevation grid from 3D point data, and from there generate contour lines

 

Can the fly through be saved as a file? 

Yes, you can save a fly through as a video. From the 3D viewer click on the save the fly through button on the toolbar and you will have options to select the quality, resolution, frame rate, and format for the video recording of the fly through. 

 

If you delete something is there an undo button?

You can use the keyboard shortcut ctrl + z to undo deleting features right after you have deleted them. This undo function only covers the last feature(s) you deleted and will not work if you delete a feature and then perform another action in Global Mapper. 

 

Is the profile view 1:1 or is it vertically exaggerated? 

The path profile view is exaggerated to fill the path profile window. There are values noted on both the x and y axes of the profile view. You can specify a specific elevation range or scale for this tool in the Path Profile Settings

 

Can you talk about how to find free lidar data online?

There is freely available lidar data out there. In Global Mapper we include some of these sources in the Online Sources dialog. There is a LIDAR folder you can expand and the sources listed here will link you to an organization’s download page where you can then download data for your area of interest. 

 

Do the menu tiles – icons highlight only when applicable choice? The pencil selects as edit – the feature chosen triggers other option choices?

Specific to the digitizer toolbars, you may have noticed that some tool icons appear grayed out and are unable to be selected. This is true for many feature editing tools until you select a feature with the digitizer. Once you have a feature selected you should see these options brighten and be selectable based on the feature(s) you have selected. 

 

What do the tree and building toolbar buttons do?

These buttons are part of the Lidar Classification toolbars that are used to work with point cloud data in the Lidar Module. We will be talking about the Lidar Module in the next GeoTalks Express session on April 15th. 

We do have previously recorded webinars and videos that specifically focus on and talk about the Lidar Module if you are interested in learning more about this module now. You can find these videos here on our YouTube channel

 

How are the lat and long extents set up in the map layout editor?

When you create a map layout you select with the bounds or the scale and center point of the data that should be displayed in the map layout. To add coordinate grid elements to the map, click to select the map frame then right-click and select Properties. Here you can edit the map view element and on the Grid Fram tab add coordinate grid information to the map view. 

 

Can we georeference a scanned map in Global Mapper? 

Yes, you can georeference scanned maps and other layers in Global Mapper. To georeference a layer you would use the Rectification tool. For this tool you should start by loading some reference data into Global Mapper, then from the File menu select Rectify (geo reference) Imagery to load your scanned map image and open the Image Rectifier dialog. 

 

Is there any way to create contours with intervals less than 1m or 1ft?

Yes, you can specify a contour interval in the contour generation tool dialog. The only unit options are meters and feet, but you can use decimal values to specify a smaller contour interval. 

 

Can you export a path profile as a point or CSV file?

You can export a path profile to multiple formats from the File menu in the path profile dialog. From this menu you have options to export the profile as a CSV or XYZ file. 

 

Can Global Mapper incorporate multiple surface models so the profile view shows more than one profile? 

Yes, if you have multiple overlapping terrain layers loaded in Global Mapper you can create a path profile view that will show separate lines for all terrain layers. To enable this option you will need to go to the Path Profile Settings and check the option to Draw Separate Line for Path from Each Terrain Layer. In addition you can enable the option to Draw Legend when Drawing Separate Layer Lines

 

When importing USG 3DEP elevation data – is there a way to know its accuracy and time/date of collection?

Blue Marble does not create or update any of the data streamed from the online sources. For more information on any built-in online source, image or otherwise, you can right-click on the source name from the Online Sources dialog and select to Display Source Web Page/Terms of Service

 

Can you create a contour map from the lake points or a thematic map? Like a heat map?

From the lake depth points used as an example, you could generate an elevation grid to show depth, and generate contour lines from that gridded elevation layer. 

You can create a thematic map by changing the point style for the lake depth points in the layer options. 

Global Mapper also has a density or heat map tool that you can use to show clusters of points or attribute values. 

 

How can you extract an area to AutoCAD Civil 3D? Image? Terrain?

Global Mapper supports many file formats for both import and export. For vector features these do include common AutoCad formats DWG and DXF. For raster image and elevation formats Global Mapper has many options including JP2000 (image), GeoTIFF (image or elevation), and DEM (elevation). Are there specific formats you are looking to work with?

 

Can you do image registration in Global Mapper?

You can georeference images and other layers in Global Mapper. To georeference a layer you would use the Rectification tool. For this tool you should start by loading some reference data into Global Mapper, then from the File menu select Rectify (geo reference) Imagery to load your scanned map image and open the Image Rectifier dialog. If you are looking to adjust the rectification for a layer, right-click on the layer in the control center and select Rectify

 

Can you make final presentation plots with title box and other presentation features?

Yes, you can create maps with titles, legends, and other elements using the Map Layout Editor. From here you can export the pages to PDF files or images for use in presentations. 

 

Can you use this to show areas of a certain percent slope, like slopes greater than 20%?

In Global Mapper you can use a custom shader to show specific slope values or slopes over a certain threshold in a different color. When creating a custom shader the slope values should be specified as degrees. 

You also have the option to create vector features from slope values by using the Create Areas from Equal Values tool. You can then search these vector features to identify and work further with a specific slope value or range of values. 

 

Can the 3D-views generated by the fly-through tool all be exported in a batch?

If you have multiple fly-through paths defined in Global Mapper, when you go to save the fly-through you will be prompted to select a path in the Fly-Through Options dialog. You can select All Paths which will play and record all the fly throughs back to back recording them to one video file.

 

Are there any size limits on vector files?

Although there are no size limits on files when working in Global Mapper, you should make sure that your computer is powerful enough to handle the size of data you are working with and the processes you are running. We do have some system requirements and recommendations for running Global Mapper, but an issue some users run into is insufficient memory when performing analysis functions with large datasets. 

 

Is it possible to change the units in the path profile?

Yes, you can change the distance units in Global Mapper and the elevation units used in the Path Profile tool. To change the distance units (x axis units in the path profile) go to Configuration > General > Measure/Units and change the Distance Units. To change the elevation units in the path profile (y axis units) open the Path Profile Settings and change the Elevation Display Units.

 

What projection does the feature retain? Can we specify the coordinate system when exporting?

When exporting features or layers Global Mapper will use the workspace projection to write out the files. The workspace projection is also what is used to draw and display the data in Global Mapper. This projection can be viewed, set, and changed in Configuration > Projection

 

Can you round this calculation to a desired precision?

If you are asking about precision related to calculating new attributes, you can use a function to specify a number of decimal places for a numeric value. 

  • FIXED(expression1 [, expression2]) : Formats expression1 as a numeric value, to an optional number of decimal places, specified by expression2, if present; if it’s not present, then the default is 2 decimal places.

 

Do you have more style options for the scale bar?

In the Map Layout Editor you can edit the scale bar feature to customize aspects like font, spacing, and color. All added elements are able to be edited like this in the Map Layout Editor. 

 

If you crop and image, can you export only the cropped area and if so, what resolution will it keep? 

When you crop an image the image still displays with the original resolution. When exporting an image Global Mapper will export the image that is shown, so if an area is cropped out that area will not be exported. In the export options you do have the option to specify the resolution for the exported image. 

 

I’m a secondary science teacher (grades 7-12) that teaches earth science. Do you think the global mapper can be applied to teaching topographic mapping? It seems a bit too difficult for students (who are around 14-15 years old) to use, but maybe there’s something that I could do with it as a demonstration tool.

In Global Mapper you can most certainly work with and create topographic maps. Take a look at the generate contours tool to show and have students understand how contour lines fit a gridded elevation surface. With the 3D viewer and path profile tool you could show how the 3D data/information is translated to a flat or 2D map. 

If you are unfamiliar with Global Mapper I encourage you to request a trial license and start by looking at the Getting Started Guide, and maybe some of our self training lessons

 

How do we change the openspace label zoom during exporting raster images?

When viewing online data, like the World Street Maps or Open Street Maps data, that has labeled areas and features, these labels are part of the raster image. This means that the scale of the features and labels is linked to the zoom level of the online source.

You can control some of the detail shown for online layers on the Display tab of the layer options. In this dialog you should see a slider for Online Layer Detail Offset that can be used to adjust the amount of detail shown based on using a higher or lower zoom level for the online data. 

 

How can I generate a database of points over the image?

If you are looking to generate a regular grid of point features over a loaded image layer, you can use the Create Regular Grid of Features tool from the digitizer (advanced) toolbar. This tool will generate a grid of features (points, lines, or areas) and you can select under Grid Placement/Orientation to fill rectangle. Using the Select Rectangle button you can then set the bounds to the bounds of a specific image layer.

 

Can I draw a line joining the deepest or shallowest depth points of a dataset?

With the digitizer tools in Global Mapper you can select specific points and then choose to create lines features from selected points. To select points to connect into lines, you can search the vector data for features based on an attribute value and select them, or select features more directly with the digitizer tool. 

Additionally, you can generate a gridded elevation layer for the depth points and then perform further analysis. Some analysis functions Global Mapper supports are the generation of contour lines and watershed and stream creation over an area of known elevation. 

I see that you were interested in creating or working with a bathymetric surface with water shading

If you do not have a bathymetric surface, but instead have point features like in the Lake Depth example shown during the GeoTalks Express session, you can generate a gridded layer from this 3D vector data. You can then shade this layer with any of the built in shaders, or create a custom shader to show the colors/values you would like. 

You also have an option to display a water level at a specific elevation which would allow you to show a water line along a coastal area or bank. 

Geo-Challenge — March 2020 Answers

How Well Did You Do?

Name the Island? – Réunion

 

Name the Country? – Poland

 

Name the Monolith? – Rock of Gibraltar

 

Name the River? – Niger River

 

Name the Capital Cities? – La Paz and Sucre

Got a Drone? Now What? — Using Global Mapper with Your UAV

Let’s start with a question. How many of you currently own a Segway? Unless you moonlight as a mall cop or run an urban tour company, you probably decided not to jump on that gyroscopically-controlled bandwagon. If the hype that surrounded the release of this ‘revolutionary technology’ was to be believed, we would long since have abandoned our cars, redesigned our cities, and be living much more fulfilling lives. Alas, the reality has fallen a little short.

The emergence and proliferation of Unmanned Aerial Vehicles (UAVs) or Drones, on the other hand, while not accompanied by a cacophony of hyped-up fanfare, promises to have a much more profound impact on our lives. If current speculation is to be believed, within a few short years, the skies overhead will be swarming with delivery drones, traffic monitoring drones, and even people-moving drones.

For those of us in the mapping industry, this eye-in-the-sky technology effectively addresses one of the perennial challenges that we face: where do we get data, and more specifically, where do we get current data? Traditionally, we have depended on often inadequate and outdated public geospatial data archives or expensive commercial sources. With the advent of readily accessible UAV technology, on-demand data is within anyone’s reach.

The rapid growth of UAV ownership has resulted in an interesting dilemma for some would-be pilots. Having purchased the hardware and collected some data, many are often unclear as to what exactly they can do with it? Over the last couple of years, I have attended several UAV-focused tradeshows and a question that I am often asked is, ‘What can I do with Global Mapper?’ The answer: many things.

Initial Flight Planning

Among the freely available online data services in Global Mapper are high-resolution aerial imagery, Digital Elevation Models (DEMs), aviation charts, and topographic maps.

Before hitting the launch button, it is a good idea to virtually reconnoiter the project area. What possible obstructions are in the vicinity, what are the terrain characteristics, are there any nearby buildings or other facilities that might have overflight restrictions, what is the coverage area? These questions and more can be answered by loading the relevant data into Global Mapper and conducting some rudimentary pre-flight analysis. Among the freely available online data services are high-resolution aerial imagery, Digital Elevation Models (DEMs), aviation charts, and topographic maps. Global Mapper’s drawing tools can be used to delineate the extent of the project site to determine coverage area and to draft an initial flight plan to optimize the data capture process. All of this data can be transferred to an iOS or Android device running Global Mapper Mobile to allow field checking of the flight plan parameters.

Geotagged Image Viewing

Images can be loaded into Global Mapper as picture points creating a geographic photo album. Derived from the coordinate values embedded in the image files, the location at which each photo was taken is represented by a camera icon in the map view.

One of the most basic functions of a UAV is taking photographs and as we will discuss below, with sufficient overlap, these images can be processed into a 3D representation of the local area. Before proceeding with this more advanced functionality, the images themselves can be loaded into Global Mapper as picture points creating a geographic photo album. Derived from the coordinate values embedded in the image files, the location at which each photo was taken is represented by a camera icon in the map view. Using Global Mapper’s Feature Info tool, each photo is displayed using the computer’s default image viewer. Viewed in the 3D Viewer, the camera icons will appear above the terrain or ground providing a precise representation of the drone’s altitude when each image was captured.

3D Reconstruction

The functionality of the Pixels to Points tool transforms simple drone-collected image files into a dataset that can be used for countless 3D analysis procedures.

Incorporated into the optional LiDAR Module, beginning with the version 19 release of Global Mapper, the Pixels to Points tool is used to analyze an array of overlapping images to create a 3D representation of the environment. This powerful component identifies recurring patterns of pixels within multiple photographs and employs the basic principles of photogrammetry to determine the three-dimensional structure of the corresponding surfaces. While the underlying technology is extremely complex, as is typical in Global Mapper, the user’s experience is very straightforward. Simply load the images, apply the necessary settings for the camera system, add ground control points if available, click the Run button, and wait while it creates a high-density point cloud and, if required, a 3D model or mesh. The functionality of the Pixels to Points tool transforms simple drone-collected image files into a dataset that can be used for countless 3D analysis procedures.

Orthoimage Creation

A byproduct of the aforementioned point cloud generation process is the option to create an orthoimage. Defined as a raster layer in which each pixel’s coordinates are geographically correct, the orthoimage is generated by gridding the RGB values in the point cloud. Given its inherent accuracy, this 2D imagery layer can be used for precise measurements or as a base layer for digitizing or drawing operations.

DTM creation and Terrain Analysis

Global Mapper can generate a Digital Terrain Model (DTM) from point cloud data.

As mentioned previously, the Pixels to Points-generated point cloud represents the raw material for numerous analysis procedures in Global Mapper. As with any unprocessed dataset, some QA, cleanup, and processing will be required before embarking on any meaningful workflow. Fortunately, the software offers a plethora of editing and filtering options, including noise point removal, spatial cropping, ground point identification, and automatic reclassification. After isolating the points representing bare earth, the gridding tool is employed to create a Digital Terrain Model (DTM), a 3D raster layer that depicts the ground surface. In turn, this terrain layer can be used to create custom contour lines, to calculate volume, to delineate a watershed, to conduct line-of-site analysis, and, if overlaid on a previously created DTM, to identify and measure change over time.

Video Playback

Aside from capturing still images, most UAVs are equipped with the necessary hardware to record video. Beyond simple recreational use, this functionality is useful for building or asset inspection, strategic reconnaissance, forestry inspection, and in countless other situations where a remote perspective is needed. Global Mapper includes an embedded video player that will play this recording while displaying the corresponding position of the UAV in the map window. The determination of position is derived from the per-vertex time stamp recorded in the track file recorded during the flight. After loading this file as a line feature, and associating it with the corresponding video file, the playback is initiated from the Digitizer’s right-click menu.

LiDAR Processing

The Global Mapper LiDAR Module offers a set of tools for identifying, reclassifying, and extracting these features as vector objects.

Not too long ago, it was generally accepted that, due of the size and weight of the required equipment, LiDAR collection could only be carried out using a manned aircraft. This simple fact contributed to the high cost and logistical challenges of the LiDAR collection process. Today, miniaturization of the LiDAR apparatus has reached the point where it is within the payload capacity of many larger drones. Given the limited range of the aircraft, drone-collected LiDAR is only viable for small, localized projects however it does allow frequent re-flying of a project site and is thus ideally suited for change detection. Global Mapper, along with the accompanying LiDAR Module, offers a wide range of tools for processing LiDAR data. As previously mentioned, points can be filtered and edited before creating a surface model for terrain analysis. Compared to photogrammetrically created point cloud data, LiDAR provides a more complete three-dimensional representation of non-ground features such as buildings, powerlines, and trees. The LiDAR Module offers a set of tools for identifying, reclassifying, and extracting these features as vector objects.

Fundamentally, UAVs and maps have much in common. Both are intended to provide a remote, detached perspective of an area of interest and allow us to see spatial distribution and patterns in our data that would not otherwise be detectable. It is understandable, therefore, that one of the primary functions of a drone is to provide data that can be used for creating maps and other spatial datasets. Global Mapper is ideally suited for this type of workflow and it provides an extensive list of tools that can be used by drone operators.


A thirty-year veteran in the field of GIS and mapping, and a lifelong geographer, David McKittrick is currently Outreach and Training Manager at Blue Marble Geographics. A graduate of the University of Ulster in Northern Ireland, McKittrick’s experience encompasses many aspects of the geospatial industry, including cartographic production, data management, marketing and sales, as well as software training and implementation services. McKittrick has designed and delivered hundreds of GIS training classes, seminars, and presentations and has authored dozens of articles and papers for numerous business and trade publications.

 

How to Compare Point Clouds Using Global Mapper v21.1

Written by: Mackenzie Mills,  Application Specialist

In many areas of GIS,  change detection can be a powerful analysis tool. Comparing datasets through time can add another dimension to your work as you can visualize and measure how a study area changes. This type of analysis is becoming particularly important as drone mapping and collection of first-hand data are more common. Change detection analysis can also be very useful when looking for natural change in an area, like the impact of a natural disaster or new vegetation growth year to year; or a man-made change, like the progress of construction in an area or deforestation; or change made to the data by previous edits.

In the release of Global Mapper version 21.1, the Compare Clouds tool was introduced to detect change points between overlapping lidar or point cloud layers. Previously in Global Mapper, change detection was only available using the Combine/Compare Terrain Grid tool, which creates a new elevation layer based on the difference in the per-pixel Z-values of the overlapping layers using the subtraction setting.  The output of the new Compare Clouds tool is a layer containing the points that have changed between the input point clouds. 

To use the Compare Cloud tool, start by loading the point clouds you would like to compare into Global Mapper. Select the Compare Could tool from the Lidar Tools toolbar. 

Compare Lidar Point Clouds
Compare Lidar Point Clouds

In the Point Cloud(s) to Compare Against box, select the starting or original point cloud. This is typically the first or earlier pass over an area. The cloud(s) selected in the Point Cloud(s) to Find Changes In box will be compared to the “Point Cloud(s) to Compare Against when the tool is run.

This new tool works to compare point clouds by having the user input a distance to use for comparison. This Minimum Distance Between Point Clouds value allows for a looser or tighter comparison of the clouds. This setting is important when comparing point clouds because they are made up of individual points and not interpolated like a terrain grid. It is unlikely that the point clouds you are looking to compare will contain points in the exact locations, so a threshold (specified in point spacings, meters, or feet) is required for comparison. Any points from the Find Changes In point cloud that do not have a corresponding point in the Compare Against cloud will be considered changes in the area.

When the process runs, those points in the second layer that have been found to have shifted beyond the designated threshold when compared to the original layer will be marked as having changed. After running this process, you will find a new layer added to the workspace containing only the points that have changed.

Points detected to be changed using the Compare Cloud tool in Global Mapper
Points detected to be changed using the Compare Cloud tool in Global Mapper

In the image above, you see an area of rocks where some have been removed between point cloud one and point cloud two, after running the Compare Cloud tool we see the selected (red) areas are the points detected to be changed.

After identifying change in an area using the Compare Clouds tool, you may wish to classify the points detected as changed or delete them to reconcile multiple datasets. Alternatively, you may want to generate gridded layers to show the changed areas and layer these changed grids over the original or use the Compare Against layer.

This powerful new tool speeds up the process of change detection on 3D data by directly comparing two point clouds to find points with significant change. This change detection functionality can be applied in a wide variety of industries including agriculture, forestry, and engineering. Take a look at the latest release of Global Mapper and the Lidar Module to bring this streamlined workflow into your own data analysis.

How to use Global Mapper’s Raster Reclassify tool

Written by Jeff Hatzel, Senior Application Specialist

With the release of Global Mapper v21.1 comes the addition of an exciting new tool, Raster Reclassify. The development of this tool, like so many in Global Mapper®, was heavily driven by requests from our users. The initial release of this tool allows users to modify the pixel values of a palette image. A common use case for this might be to adjust the classes with a landcover file to create a new layer with a simplified set of classes. Let’s look at a more advanced workflow: using Raster Reclassify to adjust the values of an image created from classified lidar.

Hint: If you’d like to learn about this tool in detail, review the Raster Reclassify Knowledge Base page!

Using Lidar Classification Codes to Make a Raster Layer:

If you’re familiar with the Create Elevation Grid tool in Global Mapper, you know that this tool allows you to create a terrain layer based on the elevations within the source point cloud. You may also know that when working with lidar data, this tool allows you to create a grid-based on a variety of lidar attributes and properties, for example, classifications.

Classified lidar data
Classified lidar data (left) was gridded based on its classification code to make an output raster (right).

This resulting file represents multiple lidar classes from the source point cloud. The classes follow the same color scheme used to display lidar by classification. However, it’s possible we may only have an interest in a specific set of classes or an individual class, buildings for example. We’ll address that with Raster Reclassify.

Hint: Take a look at the different Grid Type options in the Create Elevation Grid tool.

Raster Reclassify to Highlight Classes of Interest:

The Raster Reclassify tool (part of the Analysis Menu) allows you to adjust the values of the source layer. In this situation, we want to focus on buildings. We’re going to merge all non-building classes: ground, low, medium, and high vegetation, bridges, powerlines, and water. Buildings will be retained as a unique class.

Raster Reclassify
Raster Reclassify allows you to load the source palette from a reference file. You can choose which classes you want to reclassify, adjusting their description, color, etc.

This tool creates a new output layer within the current Global Mapper workspace. As you can see below, that layer will now only show the newly created classes you outline in the Raster Classification Rules section of the Raster Reclassify tool.

Source file comparison
The source file (left) compared to the reclassified layer (right). The reclassified layer now only shows two classes, based on the rules set in the Raster Reclassify tool.

Hint: Want to display different layers side-by-side in the same workspace as we’ve done in some of the above images? Check out Multiple 2D Map Views!

What’s Next?

Products created by Raster Reclassify can be used in a variety of applications. Some may be final deliverables for reclassified landcover datasets, used to make or adjust clutter grid files, or any other number of possibilities.

How will you use the Raster Reclassify tool?

Keep an eye out in the future for new functionality in this tool, including the ability to reclassify terrain data and non-palette imagery!

How to move your Single User Global Mapper® license in a few easy steps

The day has come, you received a computer upgrade at work or you finally splurged on a new laptop. The excitement and joy of finally having a faster computer with better graphics and a new operating system can quickly be diminished by the laborious task of transferring files and software to the new machine. This blog aims to alleviate some of that headache by walking you through Global Mapper’s single-user license transfer workflow. 

The first thing to do is to check the version number of your installation of Global Mapper. If you have version 20 or 21 you will be able to download the installation files directly from the Blue Marble website to your new machine. If you have version 19 or older you will need to move the installation files manually to the new computer. You’ll also want to ensure your Maintenance and Support (M&S) is still active. If you have questions or concerns about moving your license or the status of your M&S, please contact authorize@bluemarblegeo.com before moving your license.

Once you have checked your version of Global Mapper, navigate to the Help menu at the top of the screen, click “License Manager”, and the window below will open:

Blue Marble License Manager
Blue Marble License Manager

Select “Release” next to the license you would like to remove. A prompt will appear to confirm that you want to move forward. Click the “Yes” button. After the removal process is complete, you should receive a message containing the removal code for your license. This code will also be copied to your computer’s clipboard. To complete the removal, send the removal code to authorize@bluemarblegeo.com for confirmation that your license is no longer active. After the Blue Marble licensing team verifies this information, you will be able to move your license to the new machine.

It is possible that you may not receive a prompt upon removal, but do not worry, you can access it from the C: drive. On most computers, the file can be found in the following folder location: C:\ProgramData\GlobalMapper\GlobalMapper[your version number]. The ProgramData folder is hidden by default in Windows. If you can’t navigate to that directory,  you can view hidden files and folders with the instructions below.

Navigate to the search bar next to the Windows “Start” button and type “hidden files”. This will bring you to the “For Developers” prompt.

For developers window prompt
For developers window prompt

Under the heading “File Explorer”, click the “Show settings” next to “Change settings” to show hidden and system”. The Folder Options window will open, review the options and select “Show hidden files, folders, and drives”, then click the OK button. Please note these instructions are for Windows 10, for instructions on how to access “Hidden Files” in other versions of Windows please visit the Microsoft support page.

Windows File Explorer OptionsCintia Miranda | Projections
Windows File Explorer Options

Once this step is completed, you will be able to locate the Program Data folder on your C: drive. Please attach a copy of your GlobalMapper.lic_removed file in an email to authorize@bluemarblegeo.com.

Global Mapper license location on C Drive
Global Mapper license location on C Drive

The Licensing Team will then verify your license removal and you will be able to move your license to the new machine. Before beginning the licensing process, please remove your computer from all external hardware, including docking stations. Finally, follow the detailed steps to set up and obtain the license in Part I of Global Mapper’s Knowledge Base.

Remember, if you have any questions or run into any problems moving your license, our Licensing Team is available Monday – Friday 8 am – 5 pm Eastern Standard time. They can be reached by phone at 207-622-4622 ex 1146 and by email at authorize@bluemarblegeo.com

Chelsea E | Projections
Rachael Landry is a Blue Marble Geographics Marketing Assistant and an unofficial licensing guru.

Get access to Blackbeard online oil and gas data from Global Mapper 21.1

On February 19, 2020, Blue Marble Geographics® released version 21.1 of Global Mapper®. The release included many new software features, including subscription-based access to Blackbeard Data — an online data service for accessing pipeline, well, and lease information.

Blackbeard Data is primarily known for providing information to assist institutional professionals and independent investors in the acquisition of mineral assets, specifically buying oil and gas royalties.  Blackbeard Data maintains the world’s largest database of oil and gas royalty owners and the world’s largest database of oil and gas comparables built from oil auction histories, which is invaluable to many users of Global Mapper in the energy sector.

Version 21.1 of Global Mapper introduces BlackBeard Data as part of its extensive online data portal. This subscription-based service is available through an intuitive interface, enabling users to seamlessly transfer and analyze oil and gas data from Blackbeard Data to Global Mapper, saving time and effort.

Users of Global Mapper can now access Blackbeard data by following these five easy steps:

  1. Press the Connect to Online Data button in the File toolbar or File Menu
  2. Navigate to PREMIUM CONTENT > Blackbeard Oil and Gas Data
    Select a sub-layer of interest
  3. Enter your API key or visit  https://blackbearddata.com/data-products/global-mapper

    Blackbeard Data Dialogue Box - Global Mapper V21.1Blackbeard Data Dialogue Box on Global Mapper V21.1
  4. Specify the desired data bounds, then press connect.
  5. Use the Info tool to get info about WMS or WMTS layers, or open the Attribute Editor to view attributes for the vector WFS layers.

    Blackbeard Data Screen View in Global Mapper V21.1Blackbeard Data Screen View in Global Mapper V21.1

Upgrade now to version 21.1 of Global Mapper to have direct access to Blackbeard Data (with a premium subscription) — the world’s largest database of oil and gas. For more information on how to acquire version 21.1 of Global Mapper visit globalmapper.com. For more information on how to acquire Blackbeard Data premium subscription visit blackbearddata.com.