A way to improve your process if you're still processing this way: Pre process all of your photos through premiere pro with a preset you build to compensate for any barrel distortion. You can automate it pretty easily too.
Nathan nice one mate just tuning in now, I just bought Litchi and have downloaded WebODM, how have you found the software so far? Would you reccomend Litchi?
I really like WebODM. It doesn't have all the features as metashape (yet) but for the price its hard to argue. I don't do this type of image processing every day, so its hard to justify the 179$ price tag for a personal license. With regard to litchi I've never used it but if it allows you to fly a regular grid and if you can trigger your camera at the right times I'm sure it will do just fine!
Hello! I don't really understand why did you set all settings on ultra, but beforehand resized images to 3MP (or 6MP, don't know if the 2048 px is the width or height). Didn't you destroy a lot of detail and then forced to extract as much as possible from little? I'm new to all that and I'm learing so if you can explain that would be great! :) Thanks
In this survey I had almost 300 images and when I didn't resize the program timed out and refused to run. I used ultra just because I could, no real good reason. I'm pretty new to WebODM and I just wanted to make a basic tutorial that could help someone walk through the entire process. I'm not an expert on the mechanics. Sorry I know that's not a very helpful answer but the ODM community might have better answers. I found these two discussion posts that might answer your questions about resizing, pc-quality and feature quality. community.opendronemap.org/t/what-are-the-tradeoffs-with-re-sizing-images/4813 community.opendronemap.org/t/question-regarding-feature-quality-and-pc-quality/6038 Have fun with WebODM! :)
Hi Nathan, Thanks for this great video! What drone are you using? Because i tried to check the exif data from 3 drones (P4M, Mini2 and Mavic Pro) and none of them have gps accuracy or DOP. How does webODM handle that data if there is no DOP? And do you think I can I use the data from any of these drones for photogrammetry? the P4M has RTK but i realized that GPS altitude can be 40m off. also it has a shitty 2Mpix resolution in RGB so i thought i'd rather use the Mini2 or the Mavic Pro with GCPs
I used a DJI Phantom 4Pro modified by Klau Geomatics klauppk.com/UAV_Hardware/ Great question about the DOP. WebODM defaults to a DOP of 10m. This mean the maximum it will move an image in space is 10m, does not mean it will move the photo that much every time. This allows the program to move the photos as much as it wants to make them line up. Often times the amount it moves them is a whole lot closer to the actual DOP than the default. You can also assign the DOP inside the WebODM program which I did because for some reason it struggled to read in that exif data. With regard to your other questions, your probably better off using GCPs that have been measured accurately rather than rolling the dice with unknown accuracies and poor elevation data. Models created with GCPs can be pretty much as accurate as direct georeferencing provided you set up the GCPs well. Hopefully this answered your questions!
I've got an Intel i7 10th gen with a RTX 2080, 32GB of RAM and an SSD. If you have a computer that has a dedicated graphics card and a half decent processor with some ram to back it up you should be able to run the program no problem. Might just take a bit of time.
In your title you mention RTK or GCP but I didn't see anything about how to actually incorporate RTK data. Do you have a guide or can maybe point me in direction on how to do this? I have a DJI L1 camera, i use it for photogrammetry quite a bit as it has a better camera than the H20T for that. P1 is in the future but can't spend money on that atm. I also have the D-RTK2 base station and have .MRK file but don't know how to actually use this data with ODM.
The RTK corrections need to be applied before bringing the data into ODM. I'll link a video that might be helpful. I included RTK in the title because for the purposes of a survey RTK GPS is required for good accuracy if GCP aren't being used. There isn't anything special you need to do in ODM to use RTK it will process your data either way. Sorry if this caused some confusion.
Hi Nathan, Excellent videos. Quick question: If I have RTK geotagged images, but I want to also use a single GRP, do I have to check the 'force-gps' checkbox in the project settings? I am trying to correct a small 0.2 m vertical shift in a DEM by using only a single GRP. It worked in Pix4D and I am trying to see if it will also work in ODM. Any advice?
Hi Jason, thanks for the great question. Unfortunately I never experimented with that but I'm pretty sure force GPS will disregard any GCPs. If you need to apply a bias correction I'd suggest bringing your data over to QGis and applying the correction there. In my second video on this subject I show how to do that at the 12min mark ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-n3X2_xZau0k.html I hope this helps!
Please let me ask question: 1. What is the dimention of your GCP (X y z), Decimal degree for lat long and meter for Z (altitude)? 2. WebODM recently can use GPU, how to install and setting that? I was failed to install that Aside from that, This is one of great open source software.
Thanks for your questions, 1. For the GCPs I used EPSG:4326 which is in decimal degrees (Lat, Long) and meters for the elevation. The output however was in UTM coordinates so meters for x,y and z. That being said I'm pretty sure you can use any coordinate system provided you define it at the top of the text document as shown at 12:27 2. Unfortunately I cannot help you with this question, when I installed the program in September 2021 I just followed the directions provided at github.com/OpenDroneMap/WebODM/ and I didn't run into any complications. I remember the website saying that GPU acceleration wasn't quite ready yet so I didn't bother looking any further into it. Sorry. Hopefully this helped a little bit, enjoy WebODM!
@@nathangeomatics thanks, I'm new with ODM, I think it is interesting if somebody compare ODM with another tools (Pix4D, Agisoft, Drone Deploy, etc) for vertical accuracy with same dataset.
Nathan Would you be willing to share the data files from your demonstration? I learn best by doing. So if I had the files, I can process the data and use your video/transcript to get back on track if I get off course. Thanks in advance. A very well done 2-part video.
Hi, unfortunately I don't own the data I used and I can't share it. On the Open Drone Map form there is a page that has all sorts of sample data sets opendronemap.org/odm/datasets/ The 10th one on the list named "helenenschacht" has both GCP data as well as RTK so you should be able to participate in the entire WebODM part of the tutorial but you wont be able to do the accuracy assessment. Hopefully this data is sufficient and best of luck!
Hello, when Webodm asks for images and CGP file, which GCP file is to be uploaded ? The one that you create manually, or the one which is created from GCP process ? Thanks.
When you're using the GCP interface (at 12:14 in video) you use the GCP data you collected in the field. When you go to "select images and GCPs" (at 18:01 in video) to run ODM you use the GCP file that the GCP interface output. Hope this clears things up!
Adding Gcp would be a pain in the ass. We survey way more than 1K hectares, searching for pictures with gcp markers in it would be very time consuming.
I haven't used the windows version but this thread could possibly have some answers for you. community.opendronemap.org/t/windows-docker-gpu/15209/4 It seems as though its possibly just broken and will not work or it could be a driver thing or possibly antivirus related. Best of luck hopefully you can get it working!
