Help: WebODM will not accept my GCP file

I am using imagery collected by a DJI Phantom 3 of a salt marsh. I am trying to generate an orthograph using corrected points created by Trimble Pathfinder. I am loading the points into QGIS and using the Montana State UTM Converter to get my Northing/Easting, then I am using the altitude of the drone for my Z, and finally obtaining the pixel values from markers we placed on the ground in the images that correspond with the GCP. I’ve checked all of this information several times and have not been able to generate an orthograph, any insight would be very appreciated! The GCP text file I’ve been using is pasted below,

WGS84 UTM 19N
328982.2 4597787.3 106 1900 2939 IMG_01.jpg
328982.2 4597787.3 106 1932 2373 IMG_02.jpg
328982.2 4597787.3 106 1962 1823 IMG_03.jpg
329015.6 4597705.2 106 1566 0322 IMG_06.jpg
329015.6 4597705.2 106 1573 0838 IMG_07.jpg
329015.6 4597705.2 106 1412 2413 IMG_08.jpg
328993.2 4597612.9 106 3158 0799 IMG_11.jpg
328993.2 4597612.9 106 3133 1329 IMG_12.jpg
328993.2 4597612.9 106 1130 3104 IMG_13.jpg
328914.7 4597848.2 106 0860 0462 IMG_14.jpg
328914.7 4597848.2 106 0820 0985 IMG_15.jpg
328914.7 4597848.2 106 0779 1513 IMG_16.jpg
328978.9 4597546.4 106 0777 1359 IMG_17.jpg
328978.9 4597546.4 106 0814 1953 IMG_18.jpg
328978.9 4597546.4 106 0747 0748 IMG_19.jpg

Can you post the images on a dropbox/ google drive and share the link? It will be easier to download that way :smiley:

What version of opendronemap are you using? What command did you run?

I am using WebODM and I am uploading the images with the gcp text file. I believe I am using V.03. Thank you so much for the response :grinning: Here is the link to a google drive folder with the images and GCP text file.

https://drive.google.com/drive/folders/1ysNmLZYDg2vCYwMf-6U3QZcT8w3LleaV?usp=sharing

By not accepting you mean that you get an error or that processing ignores the GCP file?

Yes, at the end of processing it says that I need to include a GCP file. In the window on the side of WebODM it states that it cannot find points that match the images.

The problem is due to case sensitivity (lowercase and uppercase letters are treated differently) in the filenames listed in the GCP file. I changed the GCP file to use “.JPG” instead of “.jpg”:

WGS84 UTM 19N
328982.2 4597787.3 106 1900 2939 IMG_01.JPG
328982.2 4597787.3 106 1932 2373 IMG_02.JPG
328982.2 4597787.3 106 1962 1823 IMG_03.JPG
329015.6 4597705.2 106 1566 0322 IMG_06.JPG
329015.6 4597705.2 106 1573 0838 IMG_07.JPG
329015.6 4597705.2 106 1412 2413 IMG_08.JPG
328993.2 4597612.9 106 3158 0799 IMG_11.JPG
328993.2 4597612.9 106 3133 1329 IMG_12.JPG
328993.2 4597612.9 106 1130 3104 IMG_13.JPG
328914.7 4597848.2 106 0860 0462 IMG_14.JPG
328914.7 4597848.2 106 0820 0985 IMG_15.JPG
328914.7 4597848.2 106 0779 1513 IMG_16.JPG
328978.9 4597546.4 106 0777 1359 IMG_17.JPG
328978.9 4597546.4 106 0814 1953 IMG_18.JPG
328978.9 4597546.4 106 0747 0748 IMG_19.JPG

And it worked. I also opened an improvement request, since we should probably be less strict about case sensitivity. https://github.com/OpenDroneMap/OpenDroneMap/issues/710

OMG!
Thankyou!!! I’ve been troubleshooting this for weeks and never thought this would be the issue!!!

1 Like

I was following this Wiki on the WebODM Github and the example has lowercase appendages for the files,

This should be updated as well. Thank you again!!!

Dear All!

I use WebODM on Windows with Docker Toolbox. I would like to use GCP-s. I make the txt file named gcp_list.txt.
But I don’t know how to use it? How can I load the file to WebODM?

I copied the GCP file to the folder of my photos, but does’n work.

This is my GCP file, separated with spaces. What is wrong?

https://drive.google.com/file/d/1Z1BgsUzKr-pylxVuqea1FbKmM2Bq_mqN/view?usp=sharing

I don’t know if the crlf line endings will be an issue, but I do know we are having problems with angular coordinate systems (lat-long). You should try converting those to UTM or your local state plane CRS.

Also watch out for filename casing (.JPG vs .jpg).