Problems with JPEG output

Hello List

We're encountering a strange problem with bad quality jpeg output (png 
is fine). The jpeg image has a lot of vertical stripes in it. See below:

http://www.networkz.ch/home/rc/output.png (as it should be)
http://www.networkz.ch/home/rc/output.jpg (screwed)

I suspect it is a problem with some library, since it works fine on 
other Linux boxes. The plattform where the problem occurs is Redhat 
Enterprise Server 3, which is notorius for having old libs. However, the 
"main suspects", libjpeg and libgdk_pixbuff seem to be up to date (6b / 
0.22). We are using the Perl Image::LibRSVG binding to create the 
images. Anyone has already encountered a crippled jpeg like this? Is 
there a workaround?

I'm also generally confused regarding which version of gdk-pixbuf to 
use. The doc for Image::LibRSVG::getImageBitmap() says "This only return 
a useful value if you have compiled it with a gdk-pixbuf greater than or 
equal to *2.4*", but the newest version I find on ftp.gnome.org is the 
mentioned 0.22.

Here is some ldd output so you can see what we link against:

  $ ldd 
/usr/lib/perl5/vendor_perl/5.8.0/i386-linux-thread-multi/auto/Image/LibRSVG/LibRSVG.so 

         librsvg-2.so.2 => /usr/lib/librsvg-2.so.2 (0x00899000)
         libgdk_pixbuf-2.0.so.0 => /usr/lib/libgdk_pixbuf-2.0.so.0 
(0x00b06000)
         libm.so.6 => /lib/tls/libm.so.6 (0x0036c000)
         libgobject-2.0.so.0 => /usr/lib/libgobject-2.0.so.0 (0x0038f000)
         libgmodule-2.0.so.0 => /usr/lib/libgmodule-2.0.so.0 (0x009fc000)
         libdl.so.2 => /lib/libdl.so.2 (0x00111000)
         libglib-2.0.so.0 => /usr/lib/libglib-2.0.so.0 (0x00bd7000)
         libc.so.6 => /lib/tls/libc.so.6 (0x00114000)
         libxml2.so.2 => /usr/lib/libxml2.so.2 (0x00def000)
         libpthread.so.0 => /lib/tls/libpthread.so.0 (0x004bc000)
         libpangoft2-1.0.so.0 => /usr/lib/libpangoft2-1.0.so.0 (0x0024d000)
         libpango-1.0.so.0 => /usr/lib/libpango-1.0.so.0 (0x0026f000)
         libcairo.so.2 => /usr/lib/libcairo.so.2 (0x00a73000)
         libfontconfig.so.1 => /usr/lib/libfontconfig.so.1 (0x00d7c000)
         libfreetype.so.6 => /opt/freetype2/lib/libfreetype.so.6 
(0x002a1000)
         libz.so.1 => /usr/lib/libz.so.1 (0x002fe000)
         /lib/ld-linux.so.2 => /lib/ld-linux.so.2 (0x007cc000)
         libXrender.so.1 => /usr/X11R6/lib/libXrender.so.1 (0x00ce9000)
         libX11.so.6 => /usr/X11R6/lib/libX11.so.6 (0x005e4000)
         libpng12.so.0 => /usr/lib/libpng12.so.0 (0x0030c000)
         libexpat.so.0 => /usr/lib/libexpat.so.0 (0x0032f000)
         libXext.so.6 => /usr/X11R6/lib/libXext.so.6 (0x00401000)

  $ ldd /usr/lib/librsvg-2.so.2
         libgdk_pixbuf-2.0.so.0 => /usr/lib/libgdk_pixbuf-2.0.so.0 
(0x00bdb000)
         libxml2.so.2 => /usr/lib/libxml2.so.2 (0x00111000)
         libpthread.so.0 => /lib/tls/libpthread.so.0 (0x00304000)
         libm.so.6 => /lib/tls/libm.so.6 (0x00259000)
         libpangoft2-1.0.so.0 => /usr/lib/libpangoft2-1.0.so.0 (0x00b12000)
         libpango-1.0.so.0 => /usr/lib/libpango-1.0.so.0 (0x00840000)
         libgobject-2.0.so.0 => /opt/glib2nonrh/lib/libgobject-2.0.so.0 
(0x0077e000)
         libgmodule-2.0.so.0 => /opt/glib2nonrh/lib/libgmodule-2.0.so.0 
(0x00705000)
         libdl.so.2 => /lib/libdl.so.2 (0x00204000)
         libglib-2.0.so.0 => /opt/glib2nonrh/lib/libglib-2.0.so.0 
(0x00e40000)
         libcairo.so.2 => /usr/lib/libcairo.so.2 (0x00207000)
         libfontconfig.so.1 => /usr/lib/libfontconfig.so.1 (0x00753000)
         libfreetype.so.6 => /opt/freetype2/lib/libfreetype.so.6 
(0x0027b000)
         libz.so.1 => /usr/lib/libz.so.1 (0x0043f000)
         libc.so.6 => /lib/tls/libc.so.6 (0x00568000)
         /lib/ld-linux.so.2 => /lib/ld-linux.so.2 (0x003cf000)
         libXrender.so.1 => /usr/X11R6/lib/libXrender.so.1 (0x00486000)
         libX11.so.6 => /usr/X11R6/lib/libX11.so.6 (0x00872000)
         libpng12.so.0 => /usr/lib/libpng12.so.0 (0x002d8000)
         libexpat.so.0 => /usr/lib/libexpat.so.0 (0x003fb000)
         libXext.so.6 => /usr/X11R6/lib/libXext.so.6 (0x00314000)

Thanks in advance for any suggestions.

Best Regards
Christian


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