GNOME Bugzilla – Bug 61211
Incorrect rendering of 4 channel JPEG file
Last modified: 2010-07-10 04:06:53 UTC
This is a JPEG file created by Adobe Photoshop 3 and was received by one of my users. It displays with vertical lines throughout it in EOG, and Nautilus and Mozilla. It displays correctly (apart from colour balance) in Electric Eyes. MS PhotoEditor 2000 displays it correctly, but MS PhotoEditor 97 can't display anything. The Gimp 1.2.x claims not to be able to handle JPEG files with four channels.
Created attachment 5700 [details] Four channel JPEG file
Marking down to Low mainly because (judging from the fact that 4 channel jpegs crashed evo 100% repeatably and we still got very few reports about that) they aren't used very much.
Hey, guys. You're at only 6 open bugs, which is wonderful. AFAICT, all of these would affect a GNOME2 port of EOG but I'm not an expert. In particular, if you could go through the bugs I've marked as GNOME2 and remove that keyword from bugs that aren't, it'd be greatly appreciated as we try to get everything straightened out. Thanks! [This sort-of-spam can be filtered out by searching on 'luis doing GNOME2 work' in a mail client with body-search.]
Mozilla doesn't display anything at the moment (0.9.9) I'd say this is a GdkPixbuf bug, anyone else agree (adding federico, sorry if you already get these bug reports...)
*** Bug 81123 has been marked as a duplicate of this bug. ***
Moving to gdk-pixbuf.
Here is a patch which adds support for CMYK and YCCK images to io-jpeg.c
Created attachment 9399 [details] [review] patch
PATCH. Woot. :)
Looks good for HEAD. Looks a bit big to me for stable. What's up with the: + /* FIXME this is the conversion for the + Photoshop inverted CMYK data, in order to + convert proper CMYK, use 255 - k instead of k + througout. + */ FIXME?
I think one can distinguish proper CMYK from inverted CMYK by checking if K is actually min(C,M,Y), but I would need an uninverted CMYK image to verify this idea. Other tools seem to decide this by looking for an Adobe app marker. But this seems suboptimal to me. What if Adobe starts shipping non-broken apps ?
Committed with the Adobe marker check for now.
Reopened for pixbuf-stable.
Backported, marking as fixed. Matthias, you KICK ASS with your work on the pixbuf loaders :)
*** Bug 100061 has been marked as a duplicate of this bug. ***
The URL field has been removed from bugzilla.gnome.org. This URL was in the old URL field, and is being added as a comment so that the data is not lost. Please email bugmaster@gnome.org if you have any questions. URL: http://www.ed.ac.uk/~kenny/fourchannel.jpg