FR: read Roll Angle

[trougnouf]

Modern cameras have a digital meter which should be used to store the angle in EXIF data. This data could be used by development software to auto-rotate the pictures (eg this FR: https://github.com/darktable-org/darktable/issues/6423 )

Can the Roll Angle be added to the tags reported by exiv2 ? This would be the first step to implement such a feature in darktable.

It is shown by exiftool for some cameras such as the Nikon D850 (samples on https://raw.pixls.us/#repo ), and documented in https://exiftool.org/TagNames/Pentax.html and https://exiftool.org/TagNames/Nikon.html

I am trying to extract the tag information from my Fujifilm X-T1 and soon in a Nikon Z6

[trougnouf]

Sorry I meant to post this in exiv2, ExifTool already supports this tag.

[Phil Harvey]