6
votes
Accepted
IPTC vs XMP: how do they differ
Poring over the Wikipedia entries:
What you call "IPTC" is really the "IPTC Information Interchange Model" defined by the "International Press Telecommunications Council"....
- 18.3k
5
votes
What's the best software for reading and writing image tags to and from image meta data fields?
Phil Harvey's ExifTool seems to be the perfect choice for such a task.
This is the most comprehensive image tag reader (and manipulator), and it has perhaps the most complete catalog of the known tags ...
- 1,414
4
votes
What is the term write time referring to?
The first two are likely photo metadata (EXIF tags: DateTimeOriginal and DateTimeDigitized that are normally identical in pictures from cameras), while the third would just be the file time stamp (as ...
- 18.3k
3
votes
Is there an exif tag for face areas?
The Metadata Working Group regions tag (XMP-MWG) is the defacto standard for storing face regions. This is where most modern software stores the data whether it is embedded in the file or in an XMP ...
- 3,553
3
votes
Accepted
Can I assume the DateTimeOriginal of an image without an OffsetTimeOriginal is already in UTC?
Other than the GPS timestamps, EXIF timestamps are supposed to be set to the local time where the image was taken. The three EXIF OffsetTime* are relatively new, having only been added in EXIF 2.31, ...
- 3,553
3
votes
Time zone camera clock was set for does not match GPS timezone
I have seen ... which tell me that there is no way to set the time zone in the EXIF tag. How should I proceed here?
The most expedient solution is to change the date-time tag to the local time of the ...
- 26.7k
3
votes
Accepted
Programatic way of aggregating focal length metadata across large collection of photos
On my collection using Unix shell commands and exiftool:
Sorted by focal length:
find . -name 'IMG_????.JPG' -exec exiftool -FocalLength -p '$FocalLength' {} + | sort -n | uniq -c
Sorted by ...
- 18.3k
3
votes
Accepted
Is there any photography website where I could find photos based on exposure time, focal length, ISO...?
Flickr has some options available. This blog post shows some hidden search options available. This app gives statistics for your Flickr photos. And I know that it's possible to filter based upon ...
- 3,553
2
votes
Rename a file based on whichever tag contains the earliest or oldest date?
I have added the required steps here:
https://github.com/pratyushtewari/exif-scripts/blob/master/README.md
Set to oldest date from Exif meta or file name
Step 0 - install exiftool from below
...
- 21
2
votes
How can I extract just the value of a tag without the name using exiftool?
The -T option will hide the tag name, so you get only the value (example with a different tag ImageDescription):
exiftool -s -T -ImageDescription $HOME/Downloads/2023-02-15_HippoDayChobe.jpg
2
votes
Incorrect exif orientation on Canon 80D/60D when upside down/180 degrees?
Tested with two other Canon cameras (70D and 450D) and both exhibit the same behavior:
When used upside down (keeping the lens axis roughly horizontal) the upside-down shot gets the same orientation ...
- 18.3k
2
votes
Accepted
What's the best software for reading and writing image tags to and from image meta data fields?
ExifTool has been mentioned, another tool for this job is exiv2.
- 352
2
votes
Programatic way of aggregating focal length metadata across large collection of photos
Combination of exiftool and awk for example can do the work:
$ exiftool -FileName -FocalLength -p '$FileName:$FocalLength' -r . 2>/dev/null |awk -F: '!/xmp/ {gsub(/ mm/,"");a[$2]+=1} ...
- 10.1k
2
votes
Suspect photograph timestamp data has been altered
Not an expert in iPhone EXIF data, but a few things to check:
GPS time and other attributes
In my camera, if the picture has GPS coordinates, it also has a GPS time stamp (than can differ slightly ...
- 18.3k
2
votes
Programatic way of aggregating focal length metadata across large collection of photos
I suspect you want a more statistical answer than what I'm about to suggest, but I'll offer it anyway in case it's of use.
I use digiKam to manage my digital photo collection, and I've also given a ...
- 647
2
votes
Can I assume the DateTimeOriginal of an image without an OffsetTimeOriginal is already in UTC?
No.
First of all, you cannot reliably assume that any EXIF data at all is correct; all of it can be very trivially faked. Nor can you assume that the user even set the camera's time to anything close ...
- 352
2
votes
Accepted
Why does Jhead with the -autorot option fail to fix my photos' orientation?
This is a case of everything working as intended, but having incorrect input (i.e., garbage in, garbage out).
Two images, the original and after running jhead -autorot, should both display the same on ...
- 31.6k
2
votes
Time zone camera clock was set for does not match GPS timezone
You can manually change the date and time for the photos after uploading to google photos (under the info tab). Then your local library and Google Photos will have the same date/time organization, ...
- 12.2k
2
votes
Accepted
How can put 2 jpg images side by side in a new jpg without losing metadata or image quality?
ImageMagick can do this:
magick front-side.jpg back-side.jpg +append result.jpg
result.jpg contains a copy of the metadata from the first input file (i.e., front-side.jpg).
Regarding the jpg quality, ...
- 182
1
vote
How can put 2 jpg images side by side in a new jpg without losing metadata or image quality?
There several free image editors out there, such as Gimp, Krita and MyPaint. They are all capable of putting together two images side by side, but the actual actions will all be slightly different. ...
- 18.3k
1
vote
Why does Jhead with the -autorot option fail to fix my photos' orientation?
AFAIK (all my digital cameras and smartphones so far, but I don't know if the iPhones do it like everyone else) pictures out of the camera are encoded as the sensor got them (which means "...
- 18.3k
1
vote
Can I assume the DateTimeOriginal of an image without an OffsetTimeOriginal is already in UTC?
Likely not. If the camera doesn't record the time zone, it doesn't know about it, and has likely been set to local time by the user.
By the way, my camera (EOS 70D) doesn't encode an ...
- 18.3k
1
vote
Can I assume the DateTimeOriginal of an image without an OffsetTimeOriginal is already in UTC?
You can assume the time is in UTC and the assumption is safe to the degree that being incorrect doesn’t have important consequences.
I mean it’s one thing if you are time ordering keyboard-cat memes. ...
- 4,821
1
vote
Suspect photograph timestamp data has been altered
All photo metadata can be falsified by someone who really wants to do it. Standards like C2PA are working to fix this, but it will be a long time before all devices use their standards to put signed ...
- 156
1
vote
Accepted
How to update XMP metadata in paired JPGs in Lightroom?
XMP changes (edits) are always written into jpegs (and tiffs), it never creates a sidecar file. And you would not want to apply the same edits from the raw file to the jpeg anyway.
What you want is to ...
- 12.2k
1
vote
Migrating away from Picasa - "Write faces to XMP" changes the hashes of images
What you'll want to use are XMP sidecar files. These hold XMP data such as image face regions and IPTC Core/Ext data in a file with the same base name and an .xmp extension. They are standard when ...
- 3,553
1
vote
Migrating away from Picasa - "Write faces to XMP" changes the hashes of images
From your comments I understand you currently have an image library in Picasa, with photos which might become duplicated in the future (due to re-downloading). To ease the deduplication process you ...
- 8,408
1
vote
Is there any photography website where I could find photos based on exposure time, focal length, ISO...?
Only does tags, aperture, and shutter speed, but you could use Shutterdial, which uses Flickr's API and images to show a filtered group of photos.
- 50.5k
1
vote
Copy DNG/XMP metadata
This is already quite old, but maybe still useful for someone who finds it:
Most pragmatic solution i found for transferring edits from DNG to another DNG or the original proprietary RAWs (CR3, NEF, .....
- 11
1
vote
Is there a common subset of exif metadata tags for scanned photographs?
It really depends on why you are scanning photographs in the first place. I don't know your goals, and below is my solution for my, rather niche needs. Also, it is the solution of a person who likes ...
- 253
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