had the same problem trying to play mkv (matroska) files and I found this post some where in google.
this is what eventually helped me
on my fc6 using mplayer.
get the codecs from here
http://www1.mplayerhq.hu/MPlayer/rel...061022.tar.bz2
I've doenloaded the codecs from this link and copied them to
/usr/lib/codecs/
this didn't solved it yet and I got some permission errors
Error: /usr/lib/codecs/drvc.so: cannot restore segment prot after reloc: Permission denied
so I also copied them to
/usr/local/lib/win32/
(but i think you can skip this step.
again same permission error .
I found in google that the problem is with
SELinux blocking the ability to run dll
running the following command made every thing to work
chcon -t texrel_shlib_t /usr/lib/codecs/*.so
you can check this site for the solution
http://www.ittvis.com/services/techtip.asp?ttid=3092
I'm posting here part of my error for the sake of google searchers.
hope this helps N0
Opening video decoder: [realvid] RealVideo decoder
Error: /usr/lib/codecs/drvc.so: cannot restore segment prot after reloc: Permission denied
Win32 LoadLibrary failed to load: drvc.so, /usr/lib/codecs/drvc.so, /usr/lib/win32/drvc.so, /usr/local/lib/win32/drvc.so
Error loading dll
ERROR: Could not open required DirectShow codec drvc.so.
Read the RealVideo section of the DOCS!
VDecoder init failed
Opening video decoder: [realvid] RealVideo decoder
Error: /usr/lib/codecs/drv4.so.6.0: cannot restore segment prot after reloc: Permission denied
Win32 LoadLibrary failed to load: drv4.so.6.0, /usr/lib/codecs/drv4.so.6.0, /usr/lib/win32/drv4.so.6.0, /usr/local/lib/win32/drv4.so.6.0
Error loading dll
ERROR: Could not open required DirectShow codec drv4.so.6.0.
Read the RealVideo section of the DOCS!
VDecoder init failed
Opening video decoder: [realvid] RealVideo decoder
Win32 LoadLibrary failed to load: drv43260.dll, /usr/lib/codecs/drv43260.dll, /usr/lib/win32/drv43260.dll, /usr/local/lib/win32/drv43260.dll
Error loading dll
ERROR: Could not open required DirectShow codec drv43260.dll.
Read the RealVideo section of the DOCS!
VDecoder init failed
Opening video decoder: [realvid] RealVideo decoder
Error: /usr/lib/codecs/drvc.bundle/Contents/MacOS/drvc: cannot open shared object file: No such file or directory
Win32 LoadLibrary failed to load: drvc.bundle/Contents/MacOS/drvc, /usr/lib/codecs/drvc.bundle/Contents/MacOS/drvc, /usr/lib/win32/drvc.bundle/Contents/MacOS/drvc, /usr/local/lib/win32/drvc.bundle/Contents/MacOS/drvc
Error loading dll
ERROR: Could not open required DirectShow codec drvc.bundle/Contents/MacOS/drvc.
Read the RealVideo section of the DOCS!
VDecoder init failed
Cannot find codec matching selected -vo and video format 0x30345652.
Read DOCS/HTML/en/codecs.html!