2006.03.27 00:56 "Re: [Tiff] 3.8.1 and JPEG problem", by Joris Van Damme

Mikhail,

All right, I got the CVS problem partly figured out. I don't understand why diff wasn't showing any differences, but a new checkout gave me all your changes.

I tested again using tiffcp. The only TIFF file which is JPEG-compressed I have is in YCBCR color space. tiffcp didn't process it correctly, I believe there is a bug in it, but when I brute forced it to do

TIFFSetField(in, TIFFTAG_JPEGCOLORMODE, JPEGCOLORMODE_RGB); it worked (tiffcp -none jpg.tiff out.tiff produced an unencoded image which looks correctly).

Don't have time to compe up with correct tiffcp patch right now).

That sure sounds like there is still trouble in tif_jpeg.c...

Meanwhile, Frank checked current CVS, and found that at least addtiffo operates correctly. This addtiffo doesn't use TIFFTAG_JPEGCOLORMODE. My own tests without TIFFTAG_JPEGCOLORMODE also indicate all is fine now.

Are you absolutely sure you're working with current CVS? Did you check the changelog file and found those top entries I specified?
Are you absolutely sure you're refering to JPEG, and not OJPEG?
I don't have any experience with tiffcp. I don't even have a working build of that contrib. But if you double-check and confirm you're working with JPEG compression in current CVS, I guess I'll have to get tiffcp going on my machine and dig into it... Using TIFFTAG_JPEGCOLORMODE in tiffcp is no option as far as I'm concerned, the bug ought to be fixed instead of burried under bad logic. To this end, could you please specify exact command line parameters, and mail me all exact TIFF files you're working from as well as all files that result from your test, so that I can fully double-check and reproduce your exact problem? (Perhaps you did already and I should have paid more attention. If so, sorry.)

Best regards,

Joris Van Damme
info@awaresystems.be
http://www.awaresystems.be/
Download your free TIFF tag viewer for windows here:
http://www.awaresystems.be/imaging/tiff/astifftagviewer.html