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This is circa August 2001:

I've been mucking with mpeg2 transcoding to mpeg1.

The two projects I'm working on are making VCD's from MJPEG captures on linux 
using a DC10+ capture card and transcoding mpeg2 files to VCD that have been
extracted from my Tivo.

The most common way to do the transcode on linux is:

cat file.m2v | mpeg2dec -o YUV | yuvscale -O VCD | mpeg2enc -s -r 16 -o file.m1v

Unfortunately some of the mpeg2 files I've pulled off my tivo are a little 
screwed up and cause mpeg2dec to Seg Fault.

MPlayer has done some excellent work in regards to playing 
slighting screwed up mpeg2 files.

I wanted to use MPlayer in place of mpeg2dec in the transcode operation 
to get around these Seg Faults.

To do this I needed a YUV output from MPlayer.

I wrote a YUV output plugin for libvo that MPlayer uses. It outputs a 
YUV4MPEG format file (thats what the mjpeg tools expect)

Here is the patch. I did the diff on the current CVS snapshot of MPlayer

MPlayer-vo_YUV.patch

Unfortunately MPlayer has a ton of printf's in it and seems to rely heavily 
on stdout. I didn't want to get to into hacking MPlayer so the YUV output plugin
uses a file named tmp.yuv in the current working directory of where MPlayer is 
called.

Here is how I use it:

(I can't seem to background MPlayer because it does I/O on 
stdin and stdout and will pause when put in the background)
So in one window:

cd /mpegdirectory
mkfifo tmp.yuv
mplayer -vo YUV file.m2v

Then in another window:

cd /mpegdirectory
cat tmp.yuv | yuvscaler -O VCD | mpeg2enc -s -r 16 file.m1v


Thats It.

Good Luck.


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