**Dirac support for transcode via ffmpeg
**Tested with transcode version 0.6.14 and ffmpeg version 0.4.19-pre1 and
**ffmpeg cvs version dated 06-Aug-2005
**Author: dirac_dev@sourceforge.net

This patch allows the Dirac codec to be invoked by transcode via ffmpeg.
Dirac is an open-source video codec currently under developement. Both the 
encoder and decoder have been integrated with ffmpeg. 

These are the instructions for enabling Dirac support in transcode via ffmpeg 
source code.

1. Download Dirac 0.5.3 from
   http://sourceforge.net/projects/dirac/

2. Unpack the Dirac source
   tar xvzf dirac-0.5.3.tar.gz

3. Build and Install

   cd dirac-0.5.3
   ./configure 
   make
   make install

   The last step installs the Dirac share encoder and decoder libraries in
   /usr/local/lib (which is the default install point).
   
3. If using ffmpeg version 0.4.9-pre1

a. Download ffmpeg version 0.4.9-pre1
   http://sourceforge.net/project/showfiles.php?group_id=16082

b. Unpack ffmpeg source
   tar xvzf ffmpeg-0.4.9-pre1.tar.gz

c. Apply ffmpeg-dirac patch

   cd ffmpeg-0.4.9-pre1
   patch -p1 < ffmpeg-0.4.9-pre1-dirac-0.5.x.patch

d. Build and Install ffmpeg
   
   ./configure --enable-dirac
   make 
   make install

4. If using ffmpeg CVS version date 06-Aug-2005

a. Download ffmpeg CVS snapshot dated 06-Aug-2005
   http://www2.mplayerhq.hu/MPlayer/cvs/FFMpeg-20050806.tar.bz2

b. Unpack ffmpeg source
   tar xjvf FFMpeg-20050806.tar.bz2

c. Apply ffmpeg-dirac patch

   cd FFMpeg-20050806
   patch -p1 < FFMpeg-20050806-dirac-0.5.x.patch

d. Build and Install ffmpeg
   
   ./configure --enable-dirac
   make 
   make install

7. Download transcode version 0.6.14
   http://www.transcoding.org/cgi-bin/transcode?Download

8. Unpack transcode source
   tar xvzf transcode-0.6.14.tar.gz
   
9. Apply transcode-dirac patch

   cd transcode-0.6.14
   patch -p1 < transcode-0.6.14-dirac-0.5.x.patch
   
9. Build and Install transcode
   
   ./configure 
   make 
   make install
   

Sample Usage:
raw avi input - avi output (will write Dirac encoded data to .avi format)
transcode -i input.avi -x raw -i raw_input.avi -y ffmpeg -F dirac,null -o dirac_output.avi

mpeg4 avi input - drc output (will write Dirac encoded data to .drc format)
transcode mpeg_input.avi -y ffmpeg -F dirac-raw,null -o dirac_output.drc

transcode -i ~/dirac_test_data/squirrel/squirrel-720x576x50_420.yuv -g 720x576 -xraw,null -y ffmpeg,null -F dirac-raw -k -o tmp.drc

Both .drc and .avi encoded files can be played back in MPlayer (with the 
correct Dirac patch)

Files Changed:
export_ffmpeg.c
A 'raw_output' boolean has been added in to enable both .avi and .drc output 
for Dirac.  In MOD_close, added ability to retrieve delayed frames in encoder 
at EOF.