Billy Noble, Applications Specialist at Blue Marble Geographics, answers questions that come into the technical support inbox. In this video, Billy demonstrates how to reduce the vertex count of a vector file in Global Mapper.
After I crossed the finish line of the Trek Across Maine in 2018, I immediately signed up for the next ride without hesitation.
The cycling event takes place over three days and spans 180 miles — starting in the western mountains of Maine and ending on the state’s coast. It benefits the American Lung Association, which is why I chose it as my first cycling event to participate in. I rode in honor of my grandmother who had COPD.
When I finished the 2018 Trek, I was so excited that:
I got to see a beautiful part of the state I live in
I would be so much more confident on the next Trek because now I knew the route
But then the Trek organizers changed the route for 2019. *womp, womp, womp*
Instead of starting at Sunday River and ending in Belfast, the 2019 Trek would start and end in Brunswick, making a 186-mile loop in central Maine. The route wouldn’t “trek across” anymore, it would “trek around”.
On top of learning about the new route, I hurt my knee badly in January while doing a simple leg stretch (lame!) which was a training-changing injury. So, with a lowered confidence, I wanted to learn more about the new route.
Using Online Data and the Path Profile Tool in Global Mapper
The Trek provides GPX files for each day of the ride on the organization’s website. I downloaded these files; dragged them into Global Mapper; and uploaded elevation data, satellite imagery, and a street map from Global Mapper’s free online data sources.
Using the elevation data, I created path profile views of each of the three riding days. This allowed me to see which of the days would have the largest climbs and where those hills were located. After only a few minutes looking at the data, I could see that Day 2 would be the most challenging. Only ten miles into the 62-mile day, there would be a 375-foot climb, four 225-foot hills, and another 375-footer at mile 45.
I also explored the “design” of the route by looking at it over satellite imagery to see the vegetation and water bodies I would be riding by. Although Day 2 appeared to be the toughest, it also looked as if it would provide some beautiful views over lakes in the rural Fayette and Readfield area.
Planning Training Rides in Global Mapper
Looking at the path profiles helped me plan my own rides for training. After talking to some cyclists and looking up popular routes in my area, I planned a 28-mile training ride from my apartment in Portland to Gray that included a 375-foot climb — a hill similar to those two big ones on Day 2.
Using the Digitizer in Global Mapper and my online data, I mapped out this training ride, too.
Exporting my Map for the Road
In addition to using Global Mapper to look at the path profiles of each day of the Trek, I also used it to add vector points representing each rest stop along the route. After adding these points, I was ready to export my map as a Global Mapper Mobile Package (GMMP) file. Global Mapper 21 and Global Mapper Mobile v2 will allow for a native projection to be retained in a GMMP file. So as I exported, I chose to retain my projection, in my case just for visualization purposes.
I uploaded this file to my Global Mapper Mobile app, and planned on adding data to it while on the 186-mile ride.
Picture Points and the Measuring Tool in Global Mapper Mobile
June 14, 2019 was the first day of the Trek. I had my map in my Global Mapper Mobile app, and I was ready to start documenting my ride!
There are a few ways I could add photos to my map in Global Mapper Mobile. I could create points on my map from geotagged photos, or I could take photos right in the app and add them as attributes to previously existing points. Since I take so many photos with my iPhone camera, I chose to add photos using the Picture Point Create Mode — creating points from photos I had taken outside of Global Mapper Mobile.
I originally planned on using the app primarily for documenting my ride, but I found it useful in other instances.
When Day 2 really turned out to be the hardest day, I opened Global Mapper Mobile at the third rest stop to see the distance between me and Colby College — the destination of that day. It was a long 21.6 kilometers (13.4 miles) to ride with sore seat-bones and my disappointment in the shortage of fluffernutter sandwiches at this stop.
Global Mapper and Global Mapper Mobile: Easy as Riding a Bike
As Day 2 proved to me, riding a bike isn’t always easy. But GIS software can be!
I am not a GIS professional. I know that editing and exporting a simple map of a bike route isn’t rocket science. But Global Mapper’s user-friendliness made that non-rocket science even easier.
It took just a few minutes of viewing the route with elevation, street, and satellite data to get a better idea of what the 2019 Trek would be like. Even though exporting my Trek map to Global Mapper Mobile was the first time I had used the desktop and mobile apps in tandem, it was a very straight-forward process.
When I returned back to the office after my second Trek Across Maine, I exported my GMMP file from Global Mapper Mobile and imported it to my Global Mapper desktop. I clicked the vector point labeled “Finish Line” with the Feature Info tool, and up popped a photo of me and my Trek Across Maine team.
Immediately after that picture was taken, I signed up for Trek 2020 without hesitation.
Chelsea Ellis is Graphics and Content Coordinator at Blue Marble Geographics. Her responsibilities range from creating the new button graphics for the redesigned interface of Global Mapper 18 to editing promotional videos; from designing print marketing material to scheduling social media posts. Prior to joining the Blue Marble team, Ellis worked in graphic design at Maine newspapers, and as a freelance photographer.
In this short video tutorial, we explore Global Mapper’s contour creation capability and we discuss the various option and settings that can applied during the process. Use the links below to jump ahead to a specific section:
– Generating Elevation Polygons with the Create Contours Tool (19:06 – 22:15)
If you have questions about this topic or or about any other Global Mapper feature or function, email firstname.lastname@example.org If you are new to Global Mapper, you can download a free trial version at globalmapper.com/download
In early June, we introduced the first service pack update of Geographic Calculator 2019. The new features and functions in this version of Blue Marble’s coordinate conversion software are designed to improve its user-friendliness, accessibility, and efficiency. Although some changes seem slight, such as easier access to recently opened files, they have a big impact on user’s productivity in the software.
Here is a list of the top five new features of Geographic Calculator 2019 SP1:
1. Support for Open Document Spreadsheet (ODS) format
In Geographic Calculator 2019 SP1, we added support for the open-source table format Open Document Spreadsheets (ODS) to make Geographic Calculator more accessible to OpenOffice users.
2. Support for batch processing of Area Calculation jobs
Before the 2019 service pack, users had to process Area Calculation jobs one by one. In Geographic Calculator 2019 SP1, we’ve added batch support for performing mass calculations for multiple area files.
3. Support for the new Equal Earth projection
In 2018, Bojan Savic, Bernhard Jenny, and Tom Patterson invented the Equal Earth projection that is inspired by the Robinson projection but retains the relative size of areas. We’ve added this new projection to the long list of projections available in Geographic Calculator.
4. Bulk Export to WKT for coordinate systems
Users can now bulk export multiple coordinate systems (or coordinate transformations) together in one WKT file in Geographic Calculator 2019 SP1. This supports interoperability of data across platforms where coordinate systems may or may not be standardized. You can now manage your coordinate systems in Geographic Calculator, and then quickly export them to standardize the options in your other mapping packages for display and analysis.
5. Updates to the Project Manager
The Project Manager in this service pack version has been updated to be the one-stop-shop for users to process and see the status of jobs in one location. In previous versions of Geographic Calculator, process status was located at the bottom of the interface, taking up screen space.
Over the past 26 years, Geographic Calculator has become an industry leader for accurate coordinate reference system and datum management. This most recent version of the software streamlines user accessibility with new batch and bulk export options, and the additional support for universal and open-source formats.
This month, we reach deep into the technical support mailbag and pull out a letter from a customer who asks how to remove the collar from their raster topographic map in Global Mapper. Once again, Billy Noble is on hand to show us how this is done.
New streaming service provides high-resolution elevation data for the United States
The 3D Elevation Program (3DEP) is a USGS-initiated effort to collect and process LiDAR data and to make it publicly available, along with its derived products. The 3DEP elevation data (DEM) as well as several supplementary raster layers are now available free of charge and without use restriction to users of Global Mapper version 20.0 and higher. The 3DEP service is comprised of data from many different sources with horizontal resolutions up to 1 meter.
As an illustration of the quality of the data, the following screenshots compare the 3DEP data on the left with the 10-meter National Elevation Dataset (NED) of the same coverage area.
If you are currently using version 20.0 of Global Mapper or newer, you will automatically have access to the 3DEP data within the Online Data Sources list. Navigate to the Terrain Data section and choose USGS 3DEP Elevation.
For more information on the current status of the 3DEP and plans for future acquisition, visit www.usgs.gov/core-science-systems/ngp/3dep
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
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
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.
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.
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
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.
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.
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.
Billy Noble, Applications Specialist at Blue Marble Geographics, answers questions that come into the technical support inbox. In this video, Billy demonstrates how to find the coordinates of a point in a loaded point cloud in LAS format using Global Mapper.