Arithmetic coding in Fedora libjpeg (bug #639531)

[Adam Tkac]

On Sun, Oct 03, 2010 at 01:52:28PM +0530, Mukund Sivaraman wrote:
> Hi all
> 
> In reply to Gregory Maxwell:
> >> It's well known around the Internet that to achieve compatibility you
> >> should be conservative in what you send and liberal in what you
> >> accept. Applied to JPEG: Use only Huffman coding when encoding ?
> >> except maybe if you know that all recipients can handle arithmetic
> >> coding ? but support both encodings when decoding.
> 
> >Absolutely. This is an excellent argument and I think is sufficient to
> >justify the inclusion alone.
> 
> Thank you everyone for the replies. I did not know earlier that Fedora
> was switching to libjpeg-turbo.  I have created a new bug now:
> 
> https://bugzilla.redhat.com/show_bug.cgi?id=639672
> Add support for decoding arithmetic coded files in libjpeg-turbo
> 
> It contains a patch against upstream libjpeg-turbo HEAD, and the patch
> has been submitted upstream too:
> 
> https://sourceforge.net/tracker/?func=detail&aid=3080268&group_id=303195&atid=1278160
> 
> This patch has been tested against some arithmetic coded images.
> 
> I wish libjpeg-turbo also accepts to include creating arithmetic coded
> images too, as the project is not really going to affect creation of
> such images if an application wants to do so.  But this can be saved
> for another argument, and doesn't stand in the way of decode support.

We decided to accept arithmetic method into libjpeg-turbo upstream as
soon as Fedora legal says it's fine.

Regards, Adam

-- 
Adam Tkac, Red Hat, Inc.