GIF metadata

For my first test of Leo’s new script FilterCmd, I basically used the examples he gave in his initial post in the thread. I don’t typically use GIFs for anything, but converted a small PNG to both JPEG and GIF, and then copied his first usage code example (using PATTERN *.(JPG|JPEG|GIF|PNG)) and used it via > with a bunch of files selected. I noticed the size of the GIF file didn’t change, despite having set Comment for it. I then used ExifTool to export all metadata to a JSON, which failed to turn up anything resembling a comment string in the GIF. I assume this means that GIF comments are actually being written by DOpus to an alternate data stream, which seems to be confirmed here. But according to ExifTool’s documentation, XMP tags can be written to GIFs, and DOpus does already write XMP:UserComment (and EXIF:XPComment) to JPEGs and PNGs. Any comments, or possibility of adding support for XMP in GIFs? (Not that I particularly need it, but who knows what the future may bring.)

We don't write tags into GIF files. (XMP in GIF must be a fairly new thing, and XMP didn't exist back when GIF was still in development.)

The Comment field can be written against any file as long as it's on an NTFS drive. If it's a file type which doesn't have a known way to write a Comment into the file itself, it will be stored as NTFS ADS metadata instead.

e.g. Text files definitely have no way to store a comment (without messing up their contents/meaning), so comments on those will always go into NTFS ADS.