Locating IPTC in Photoshop segment is flaky

[GoogleCodeExporter]

IPTC info in JPEG images can be stored in the Exif IFD, or in the Photoshop
3 segment. In the latter case, if it is at the start of the segment, it can
be located with the string: Photoshop 3.0\x008BIM\x04\x04\x00\x00\x00\x00.
However, I don't know how to locate it otherwise.

Original issue reported on code.google.com by p.edel...@gmail.com on 11 Mar 2007 at 3:44

[GoogleCodeExporter]

Reference:
http://www.codeproject.com/bitmap/iptc.asp?df=100&forumid=2301&exp=0&select=6474
30

Original comment by p.edel...@gmail.com on 11 Mar 2007 at 3:48

[GoogleCodeExporter]

Maybe this helps:
http://www.accusoft.com/support/Documentation/ImageGear/13.2/Windows/Core/Active
x/Appendix%20(Non-Image%20Data%20Storage)6.html

Original comment by p.edel...@gmail.com on 12 Mar 2007 at 6:31

[GoogleCodeExporter]

This might help:
http://www.awaresystems.be/imaging/tiff/tifftags/docs/photoshopthumbnail.html

Although it describes the data in TIFF files, I think it is the same as in JPEG
(prepended by the Photoshop 3.0...string). It even mentions 8BIM.

Original comment by p.edel...@gmail.com on 14 Mar 2007 at 9:44

[GoogleCodeExporter]

There is now a Photoshop class which can parse Photoshop segments, based on the 
Aware
Systems specification. It does create a list of all the tag numbers found, with 
their
index and length, but does not interpret these tags, because we don't really 
want to
support it. It should be only used to locate the IPTC info (located at tag 1028 
or
0x0404).

Currently, the JPEG class uses the Photoshop class to find the IPTC data. The 
Aware
Systems describes that the Photoshop structure may also be embedded in TIFF 
files, so
that class should also look for it (apart from IPTC tag).

Also, the Photoshop class should get a writer method to store modified IPTC 
data.

Original comment by p.edel...@gmail.com on 15 Mar 2007 at 8:01

[GoogleCodeExporter]

Original comment by p.edel...@gmail.com on 16 Mar 2007 at 10:15

• Changed state: Started

[GoogleCodeExporter]

Should be fixed now, although it's not properly tested. This is in part 
dependent on
<a href="http://code.google.com/p/thebigpicture/issues/detail?id=2">the 
availability
to parse and write IPTC data</a>

Original comment by p.edel...@gmail.com on 16 Mar 2007 at 10:48

• Added labels: Milestone-v1-alpha1

[GoogleCodeExporter]

This issue requires testing.

Original comment by p.edel...@gmail.com on 18 Mar 2007 at 9:11

• Changed state: Testing

[GoogleCodeExporter]

Testing -> beta1

Original comment by p.edel...@gmail.com on 21 Mar 2007 at 7:42

• Added labels: Milestone-v1-beta1
• Removed labels: Milestone-v1-alpha1