I'm having a problem with the products of my D2M project. First of all, when running the project it does not create a DSM or Ortho even though I have selected them in the processing options.. I have taken a look at the Report (attached), and that actually has the correct ortho and DSM shown... So I don't understand why I don't get any products in the 2D folder..
I have created many projects before and this has never been an issue.
Second issue is, that my Point Cloud is at a wrong elevation. It is shown at a height of 169 meters, which is actually the height that is imprintet in the images themselves were they were taken. However no matter how I set the vertical coordinate system or the vertical conversion, the point cloud is still shown at the before mentioned height??
The guy who flew the images, have created a perfect result in Pix4D... He has used only standard settings and since Drone2Map is built on Pix4D technology I don't understand why I'm having this problem....
If this is a DJI Drone there can be errors in the altitude values in the image EXIF tags. There is a method of exporting and correcting the altitudes that will correct the point clouds and mesh elevations. I will look for some documentation on how to do that and get it to you.
As for the Ortho and DSM missing could you do the following:
- Edit %LOCALAPPDATA%\Programs\ArcGIS\Drone2Map\Bin\data\config\log.json
- Change the logLevel to "debug" and save the file
- Start D2M, open the project and run processing
Then send me the following (I'm PM you my email):
- Zip file containing all the files in: %LOCALAPPDATA%\Drone2Map\log
- Zip file containing all the files in: C:\Users\<user>\Documents\Drone2Map Projects\<project<\process\project\logs
- C:\Users\<user>\Documents\Drone2Map Projects\<project<\process\project\project.log
Yes it IS a DJI drone (Phantom4), so that sounds like the problem I'm experiencing. It would be most appreciated, if you could send me the documentation or lead me in the right direction :-). I also received the point cloud that he had created in Pix4D, which is also flawed in the elevation of his first flight. So Pix4D is also a "victim" of the flawed images.
I have started up a project, which usually runs for 5-6 hours, so I'll send the information to you when it is done.
Thank you for your feedback so far 🙂
Drones sometimes record inaccurate flight heights in the EXIF tags of the images causing products to be built at the wrong elevation. This includes 3D point clouds and meshes as well as 2D DSM/DTM images and contours lines. To correct the images for use in Drone2Map for ArcGIS 1.2 it is necessary to create a file with more accurate altitudes which can be imported into Drone2Map for ArcGIS 1.2.
The steps to correct image altitudes are detailed below. (Drone2Map for ArcGIS 1.3 will contain functionality to Adjust Image Altitudes automatically):
To adjust image altitudes, you will need three things:
Step #1: Creating the CSV file:
Step #2: Finding the Relative Altitude:
You will need the altitude you specified in the Mission Planning application to fly the drone at. If you remember this altitude you can proceed to the next step, if not you will need to retrieve the relative altitude from the EXIF tags of one of the project images or some other file output by the Mission Planning application (Note: Not all drones record the relative altitude).
You will only need the Relative Altitude of a single image, usually just the first image in the project (taken once the drone reached the proper altitude of course).
About : DJI Meta Data
Format : image/jpeg
Absolute Altitude : +230.33
Relative Altitude : +27.10
Other locations of Relative Altitude:
Some Mission Planning applications write additional files that may contain image information. Look in all project and text files output by the Mission Planning application.
Step #3: Getting the Orthometric Elevation:
You will only need the Orthometric Elevation of the point at which a single image was taken, usually just the first image in the project (taken once the drone reached the proper altitude of course). Since drone project areas are relatively small this elevation can be applied to the entire project to successfully produce products representing the proper elevation.
We will be adding a Ground Control Point (GCP) to the Drone2Map for ArcGIS project temporarily to get the Orthometric Elevation. This GCP can then be deleted.
Step #4: Correcting the Image Altitude values:
Step #5: Applying the corrected Image Altitude values to the project:
Step #6: Run the project:
The project will run and produce products that reflect the proper Orthometric Elevations and will hence display properly on an Orthometric basemap/surface such as those in Drone2Map for ArcGIS and ArcGIS Online.
Thank you for the very detailed step by step procedure, that gives me a great guideline for future issues 🙂
I have already extracted the EXIF data with another tool and there is no Relative Altitude data within. So I'll have to speak with my pilot about that. Otherwise everything else seems pretty straight forward.
And I'm looking forward to version 1.3 😉