fix value of DateTime in the EXIF data of exported jpgs

[blitzgneisserin]

Currently, the value of the EXIF tag DateTime in exported JPEGs is wrong because it is being copied from the raw. I would like to fix this, but I am not sure how. This is what Bing Chat suggests:

1. add -DateTime=\"$(date +'%Y:%m:%d %H:%M:%S')\" to line 119 in o-jpg/main.c
2. add -DateTime=\"now\" to line 119 in o-jpg/main.c

Which possibility would work (best)?

[ptilopteri]

would you not prefer that the resulting jpg reflect the time the image was captured rather than a "processing" date/time?

[blitzgneisserin]

That's a different EXIF tag called DateTimeOriginal, that one is not supposed to be touched. At least afaik.

[blitzgneisserin]

I mean the jpg should contain both dates, so some tag should be changed. I think it's also important to know when the raw was processed. Other raw processors such as darktable or RawTherapee usually change DateTime when they export photos.

[ptilopteri]

yes, files contain four date/time instances, Access Modify Change Birth

on a linux system, do: stat .jpg

stat ./VillageIdiots.jpg File: ./VillageIdiots.jpg Size: 33359 Blocks: 72 IO Block: 4096 regular file Device: 8,34 Inode: 357863 Links: 1 Access: (0644/-rw-r--r--) Uid: ( 1000/ paka) Gid: ( 100/ users) Access: 2024-01-21 12:22:24.702044724 -0500 Modify: 2023-10-06 09:34:54.129302067 -0400 Change: 2023-10-06 09:34:54.139302010 -0400 Birth: 2023-10-06 09:34:54.129302067 -0400

and exiftool will show: File Modification Date/Time : 2023:10:06 09:34:54-04:00 File Access Date/Time : 2024:01:21 12:22:24-05:00 File Inode Change Date/Time : 2023:10:06 09:34:54-04:00

[hanatos]

..okay exif and file time stamps are a different thing, but i think the question is valid: why do you want to update the time stamp? this is about ModifyDate?

0x0132 ModifyDate string IFD0 (called DateTime by the EXIF spec.) 0x9003 DateTimeOriginal string ExifIFD (date/time when original image was taken) 0x9004 CreateDate string ExifIFD (called DateTimeDigitized by the EXIF spec.)

[blitzgneisserin]

You are right, DateTime only updates the file timestamp, not the Date and Time in the EXIF. ModifyDate is correct. Stupid AI.

[blitzgneisserin]

I was also a bit mislead because Media Library Assistant for Wordpress also extracts ModifyDate as DateTime, apparently there is no such tag as ModifyDate in photos, but the correct exiftool command is indeed ModifyDate.

[hanatos]

https://www.heise.de/news/Schlechte-Code-Qualitaet-durch-die-KI-Assistenten-GitHub-Copilot-und-ChatGPT-9609271.html :D

[blitzgneisserin]

So the correct fix would be -ModifyDate=\"now\"? This should work on all OSs, shouldn't it?

[hanatos]

did not test, but this sounds good to me.

this will work on all os that find exiftool in /usr/bin .. i'm kinda sceptical this includes windows. i need to write some basedir/ executable search that would look for both ffmpeg and exiftool and then ship these in the zip/appimage.

On Mon, Jan 29, 2024 at 12:54 PM Anna @.***> wrote:

So the correct fix would be -ModifyDate=\"now\". This should work on all OSs, shouldn't it?

— Reply to this email directly, view it on GitHub https://github.com/hanatos/vkdt/issues/106#issuecomment-1914539415, or unsubscribe https://github.com/notifications/unsubscribe-auth/AAMAKKJN3YGNWTCAVTWPMPLYQ6EV7AVCNFSM6AAAAABCNIGHJ2VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMYTSMJUGUZTSNBRGU . You are receiving this because you commented.Message ID: @.***>

[blitzgneisserin]

I created a pull request but one of the automatic checks failed. I think something is wrong with uploading the Windows build?

[hanatos]

yeah don't worry i should probably switch this upload off if it's not run from the main repo/master branch.

merged, thanks!

On Mon, Jan 29, 2024 at 9:32 PM Anna @.***> wrote:

I created a pull request https://github.com/hanatos/vkdt/pull/107 but one of the automatic checks failed. I think something is wrong with uploading the Windows build?

— Reply to this email directly, view it on GitHub https://github.com/hanatos/vkdt/issues/106#issuecomment-1915514166, or unsubscribe https://github.com/notifications/unsubscribe-auth/AAMAKKLTXXQ32ZE7UGAR7M3YRABPXAVCNFSM6AAAAABCNIGHJ2VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMYTSMJVGUYTIMJWGY . You are receiving this because you commented.Message ID: @.***>