Adding a custom XMP tag to a Tif

PIX4Dmapper PIX4Dmapper Questions/Troubleshooting
1

Hi all,

I’m trying to calibrate my project in the Index Calculator on Step 3. DSM, Orthomosaic and Index but ONE of my UAV images is kicking back this error:

[Error]: Error e9035a: camera model name: Altum_8.0_2064x1544 (Blue), correction type: sunIrradianceAndAngleWithPoseFromIMU - Missing information for radiometric correction in 1/1155 images:
[Error]: 	IMG_0218_1.tif: No sun irradiance information No sun sensor pose information

I did some research and someone said you can just add in the sun irradiance information from a previous image capture. So in this case, IMG_0218_1.tif is missing the sun irradiance info and I want to copy the sun irradiance info from IMG_0217_1.tif over. I tried to do this in Exiftool using this command -XMP-Camera:Irradiance=“149.06368189895989” in the ExifToolGUI’s ExifTool direct tool but it just errors:

Warning: Tag 'XMP-Camera:Irradiance' is not defined
Nothing to do.
<-END-

I figured out that the Irradiance tag is not pre-defined so you need to create a custom user-defined tag but I can’t figure out how. Can someone explain to me step by step how create user-defined tags in Exiftool? Or just how to add in the sun irradiance information in general. Thanks

2

Hi Michael,

Pix4D uses exiv2 to read the exif and xmp tags, so I would recommend you to use that. The tag would be Xmp.Camera.SunSensor. You can find the information about more XMP tags here: https://support.pix4d.com/hc/en-us/articles/360016450032-Specifications-of-xmpcamera-tags

The tags would need to be exact. You can also find some info here: Camera, Sun Irradiance and Sun angle in red text - #8 by Manuel_Cubero_Castan

If you need any help in tagging let me know.

3

Ok you said I should use exiv2 but in the thread you link to, everyone ends up using ExifTool anyways.

Second, I looked at the tags in IMG_0217_1.tif and there is no XMP.Camera.SunSensor. Even if I add this tag to IMG_0218_1.tif, I wouldn’t even know what to populate it with because IMG_0217_1.tif doesn’t have that tag.

How do I figure out which tags are present in 0217 that are missing in 0218? And how do I add them to 2018?

4

Hi Michael, Could you write us a support ticket and send me your images? I will have a look and give the detailed workflow here as well for future reference. Make sure to give a link to this community post in your personal support ticket. Thanks! I look forward to assisting you with the tags.