Can't get XML block from JPEG 2000

Started by ArchivesDrone, September 24, 2015, 02:38:53 PM

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ArchivesDrone

Hi.

I'm working on a project and was running some test images through Exiftool (thank you very much for this wonderful, wonderful tool BTW) to see what the metadata in the headers looked like. I was trying to read the XML box out of the jp2 image that can be found here (http://www.loc.gov/ndnp/guidelines/examples.html) using windows exe of Exiftool 10.02 on windows 7 with the following command

exiftool -u -a -X [path to image on my desktop]

but I don't see it at all. I know the XML is there because I can see it when I open the file in a hex editor. It also shows up in the output when I run the image through JHOVE, which validates the file as well. The other metadata for the image shows up and seems OK so I'm not sure what's going on here. I've tried several variations including -scanForXMP after reading about how XML iin JPEG2000 files is treated as XMP in the tag documentation but no soap.

Help?

StarGeek

Exiftool is throwing a warning with that image, so that might be part of the problem.
Warning                         : Can't currently handle huge JPEG 2000 boxes
* Did you read FAQ #3 and use the command listed there?
* Please use the Code button for exiftool code/output.
 
* Please include your OS, Exiftool version, and type of file you're processing (MP4, JPG, etc).

ArchivesDrone

Is there a specific (or general) limit on JP2 size that Exiftool can handle? It doesn't seem a particularly large image to me. But then again I wouldn't use JP2 if I had a choice.

StarGeek

I'd guess that it's not a problem with the image size but with the metadata size or something similar.  You'll probably have to wait for Phil to respond with details.
* Did you read FAQ #3 and use the command listed there?
* Please use the Code button for exiftool code/output.
 
* Please include your OS, Exiftool version, and type of file you're processing (MP4, JPG, etc).

ArchivesDrone

The XML is less than 1200 bytes long, which also seems surprisingly short to me.

Phil Harvey

Thanks for the sample.  I don't recall ever seeing an example of a huge JP2 box before.

I'll take a closer look at this and consult the Jpeg2000 specification to see how easy it would be to add support for huge boxes.  Hopefully I can do this tomorrow, but if not it will be early next week.

- Phil
...where DIR is the name of a directory/folder containing the images.  On Mac/Linux/PowerShell, use single quotes (') instead of double quotes (") around arguments containing a dollar sign ($).

Phil Harvey

I've taken a look at this and consulted the JPEG2000 specification.

I'll add support for the huge JP2 box format in ExifTool 10.03.

Thanks for bringing this to my attention, and for the sample image.

- Phil
...where DIR is the name of a directory/folder containing the images.  On Mac/Linux/PowerShell, use single quotes (') instead of double quotes (") around arguments containing a dollar sign ($).

ArchivesDrone

Sorry for my late reply. Thank you for your prompt attention and for all the work you do to provide this invaluable tool. I literally could not do my job without it. Thanks again.