Re: [GD-DEVEL] Color bug in JPEG output with 2.0.36

On Sun, Mar 30, 2008 at 11:48 AM, Pierre Joye <[email protected]> wrote:
> Hi Ethan!
>
>
>  On Sun, Mar 30, 2008 at 6:01 AM, Ethan A Merritt
>  <[email protected]> wrote:
>  > I am forwarding a bug report from a gnuplot user who
>  >  tried out the current gd 2.0.36RC:
>
>  Thanks for this report! If it persists after our tests, can you open
>  an issue in bugs.libgd.org please?
>
>
>  >  > I updated from 2.0.33 to the most recent test version, 2.0.36RC.  The JPEG
>  >  > test no longer segfaults.  However, the color of the sinusoid is brown
>  >  > instead of bright red as it is for the PNG output.
>  >
>  >  And indeed, I can confirm that the colors coming out of JPEG are
>  >  strange.  In particular, pure red is rendered as brown.
>
>  As far as I can see, we did not change the JPEG codec since 2.0.29
>  except a sanity check
>  (http://cvs.php.net/viewvc.cgi/gd/libgd/src/gd_jpeg.c). I can't
>  reproduce the problem (if I got it correctly) here (linux/windows, 32
>  or 64bit).
>
>  Can you try using the attached code (result image attached too)?
>
>  Also it would help to have the script to reproduce it (gnuplot, c, php or perl).

I suppose you are referring to:

[ 1929002 ] Bad PNG right border / JPEG seg fault
and
[ 1929227 ] Possible PNG/JPEG color issues


I figured out the source of the "brown" red and posted the explanation in:

http://sourceforge.net/tracker/index.php?func=detail&aid=1929002&group_id=2055&atid=102055

About #1929227, I'm not sure what he is trying to achieve but it looks
like he is a bit confused about background, transparent color, jpeg
and PNG limitations. I'll be happy to provide further help as soon as
I got more info about what exactly is his goal or issue.

Thanks again for your head up!

Cheers,
-- 
Pierre
http://blog.thepimp.net | http://www.libgd.org