michel038 wrote: Sun Oct 01, 2023 7:48 pm
Raw files do not support IPTC metadata ... but only XMP
Then how Photo Mechanic v6 is able to embed IPTC into RAW files and its been read by XnView MP
and ExifTool shows it as IPTC tags
michel038 wrote: Sun Oct 01, 2023 7:48 pmSome raw files support embedded xmp metadata, some others need a companion (sidecar) file where xmp informations will be written
From what i understood in this thread on DP Review its mainly not done to avoid possibly rare cases of raw files becoming corrupt, however i have updated all my RAW files with ExifTool to replace preview image like 3 times and never had a single corrupt file out of 26,000 files.
I think user of XnView Mp should have option (perhaps hidden option in xnview.ini file) to update raw files directly instead of using .xmp that mostly the filesystem.
I've never come across a case where the colour labels are recorded in IPTC. It seems that 90% of (french) Google's responses on this subject concern Photomechanic (and interoperability difficulties). Some NEF files can also carry IPTC data. This seems to me to be very unusual.
Picture from https://iptc.org/standards/photo-metada ... -standard/ , containing all(?) normalized(?) metadata.(Edit : IPTC metadata)
This copy has lost it's XMP star rating when I changed it's size with xnviewmp
Most data called "iptc" are in xmp space (Iptc4xmpCore , Iptc4xmpExt)
Last edited by michel038 on Sun Oct 01, 2023 9:39 pm, edited 1 time in total.
I have noticed there's file called country.txt inside XnViewMP folder, is it to be used for IPTC Content Location Code & Content Location Name tags?
If so how i set it?
philalethia wrote: Mon Oct 02, 2023 1:52 pm
...and why this isn't recognized as the serious flaw/bug, that it is...
michel038 wrote: Sun Oct 01, 2023 7:48 pmRaw files do not support IPTC metadata ... but only XMP
XnViewMP already writes IPTC data to RAW files (and saves old file with _Original added after extension) when use Metadata > Edit IPTC... (Ctrl + I) and click Write button, therefore it should at least give option to write IPTC to raw when i change Rating, Label and Tagging (checkbox) and use View > Update files from catalog.
Method
I've always tried to find the best compatibility for metadata, and the most likely stability and universality of methods. I advised friends and colleagues along these lines. Marking your photos is a big job that needs to be done consistently and thought through over the long, or very long, term.
IPTC
At the end of the 90s, IPTC seemed to offer these guarantees and I was wary of Adobe and its proprietary xmp format. For a long time, many software packages only supported IPTC.
XMP
Then XMP came along and offered to provide fields corresponding to those in IPTC for compatibility purposes. IPTC 'agreed' to be integrated into this format (iptc4xmp, iptc ext : it's not a survival of iptc, it's xmp that can mirror iptc ), and the most recent software supports xmp. Since then, I've been using IPTC and XMP in parallel before I will be sure to abandon iptc, maybe in 2024.
RAW
The great diversity of raw formats, the absence of standardisation (as exists for jpg) and the reluctance of many users or developers to embed XMP metadata into files meant that I refused to attempt this operation, and I prefer to use sidecars to add my metadata, although sidecars are an inelegant solution. (in reality I archive raw and catalogue jpg copies.If necessary, I'll be able to generate xmp sidecars from jpg's, and carry them into raw folders).
Now , there are softwares offering to integrate IPTC into raw formats, when this standard is on the way out (or at least being absorbed by xmp), I think it's risky to rely on this random method 20 years too late.
But you're right: it's often possible to embed IPTC data into some raw files that support it.
The standardisation of star ratings and colour labels in IPTC seems uncertain to me.
Please bear in mind that this is an automatic translation (deepl.com) subject to a few inaccuracies.
michel038 wrote: Wed Oct 04, 2023 8:20 pm
I've always tried to find the best compatibility for metadata, and the most likely stability and universality of methods. I advised friends and colleagues along these lines. Marking your photos is a big job that needs to be done consistently and thought through over the long, or very long, term.
IPTC
At the end of the 90s, IPTC seemed to offer these guarantees and I was wary of Adobe and its proprietary xmp format. For a long time, many software packages only supported IPTC.
XMP
Then XMP came along and offered to provide fields corresponding to those in IPTC for compatibility purposes. IPTC 'agreed' to be integrated into this format (iptc4xmp, iptc ext : it's not a survival of iptc, it's xmp that can mirror iptc ), and the most recent software supports xmp. Since then, I've been using IPTC and XMP in parallel before I will be sure to abandon iptc, maybe in 2024.
I am new to metadata, for organizing files, just started with this week. I don't really care much if its EXIF fields i write to RAW file or IPTS or XMP as long as this data is written inside RAW file itself.
From my point of view sidecar .XMP files are mess:
- they are clogging hard drive slowing down system.
- easy to loose when for example when moving raws using tool like PhotoMove v2.5, that i use often now days to change organizational order of my files.
- .xmp files are being used by Photoshop so it will dump more junk info in this, some odd photo viewers also leave their own metadata inside xmp files or for some unknown reason copy exif data to .XMP file, making them even bigger.
Tagging often mean "adding metadata'", not only keywords... French can use " étiquetage " (labeling) for metadata, "marquage" for adding marks, and "tagging" has no standard translation. I don't know which words are the best choice in English.
The best way for me is to read a manual when it exists, (or write a manual ! that's what I did)
Pierre is the only développer, XnViewMp is free for personal usage, it's a lot of work and a great gift which deserves respect and delicacy.
The few people that have enough courage to tag photos should spent a while to understand what they have to do, and discover how to correctly use the software as it is...
