ExifTool Forum

ExifTool => The "exiftool" Application => Topic started by: grubin698 on March 20, 2025, 09:02:54 AM

Title: getting data out of unknown tags
Post by: grubin698 on March 20, 2025, 09:02:54 AM
Good morning,
I have a tif containing a radiographic (x-ray) image with associated metadata that was created by the x-ray capture software.
Using the Python exifread library, I can see that there is a tag called 0xFE68 that contains what looks to be a JSON-formatted string.
Screenshot 2025-03-20 085342.png
Screenshot 2025-03-20 085443.png
I'd like to replace the exifread library with exiftool, but I'm having trouble getting the full JSON-formatted string out of exiftool. 
I've tried various versions of stuff I've found about getting at unknown tag data, but have yet to get the full string.
exiftool -u -exif_0xfe68  "radiograph.tif" > "H:\DATA\Laptop Xrays\xfe68.json" yields Exif 0xfe68                     : {"IsFavorite":false,"BackupFile":"","Setup":{"Type":"XT[...]
I've also tried -u -ee -exif_0xfe68-u -ee3 -exif_0xfe68and even -U -G3:1 -api requestall=3 -api largefilesupport -exif_0xfe68 but have yet to stumble upon the magic combination of switches that will give me the whole string. 
Title: Re: getting data out of unknown tags
Post by: Phil Harvey on March 20, 2025, 09:33:39 AM
Your first try was very close.  All you needed to do was set the LimitLongValues (https://exiftool.org/ExifTool.html#LimitLongValues) option:  -api limitlongvalues=0

Also, you should add -s3 if you want to redirect the output to a JSON-format file.

- Phil
Title: Re: getting data out of unknown tags
Post by: grubin698 on March 20, 2025, 10:12:25 AM
Perfect! Thanks!
Title: Re: getting data out of unknown tags
Post by: StarGeek on March 20, 2025, 10:47:08 AM
Quote from: Phil Harvey on March 20, 2025, 09:33:39 AMYour first try was very close.  All you needed to do was set the LimitLongValues (https://exiftool.org/ExifTool.html#LimitLongValues) option:  -api limitlongvalues=0

Also, you should add -s3 if you want to redirect the output to a JSON-format file.

Would the -b (-binary) option (https://exiftool.org/exiftool_pod.html#b---b--binary---binary) also have worked? Without need of the -api option?
Title: Re: getting data out of unknown tags
Post by: Phil Harvey on March 20, 2025, 11:44:50 AM
Quote from: StarGeek on March 20, 2025, 10:47:08 AMWould the -b (-binary) option (https://exiftool.org/exiftool_pod.html#b---b--binary---binary) also have worked? Without need of the -api option?

Good point.  That would have been simpler. :)  ... TIMTOWTDI

- Phil