Inconsistence of exported metadata to *.xmp vs. *.xml - the -rawimagedigest tag

[cs]

Hello,

in reference to: https://exiftool.org/forum/index.php?topic=2734.0
a md5 checksum on the sensor data is a usefull primary key for a capture.
But the quoted call of exiftool don't work. I must kill the job with ctr-c.

[worked]

Code Select Expand

exiftool -rawimagedigest="checksum" image.jpg|raf

Code Select Expand

exiftool   -tagsfromfile   image.jpg|raf   image.xml
The tag -rawimagedigest is exported.
Any manipulation of the -rawimagedigest tag *.xml also worded fine.

[Don't worked]

Code Select Expand

exiftool -tagsfromfile  image.jpg|raf   image.xmp
The tag -rawimagedigest isn't exported.

Code Select Expand

exiftool   -rawimagedigest="checksum"    image.xmp
The tag won't be written.


Is there any sense about this behavior of exiftool out in the dark that I don't see?
https://exiftool.org/TagNames/index.html
"The Writable column indicates whether the tag is writable by ExifTool. Anything but a no in this column means the tag is writable."

Greetings

C's

Environment:
exiftool 11.00
perl 5, version 26, subversion 2 (v5.26.2) built for x86_64-linux-thread-multi
Arch Linux

[Phil Harvey]

RawImageDigest is an EXIF tag.  It doesn't exist in XMP.

If you want it written to XMP, you need to create a user-defined tag.

- Phil