[MEncoder-users] Creating raw YUV files from movies or images

[Ola Jetlund]

Hi,

for my work I need to create raw YUV files. That is videofiles that 
consists of uncoded images in a sequence - the most basic form of a 
video file.

I thought that both mencoder and mplayer wore able to export such files 
(from the documentation). I guess I was wrong. For instance trying the 
yuv4mpeg options or dumpstream option produces a YUV file with a header 
- which is NOT what I want - especially since trying to play it without 
the header produces rubbish.

The test for wether or not a YUV-file is actually raw is the following

             mplayer -rawvideo on:fps=30:w=352:h=288 raw_yuv_movie_cif.yuv

if this is something that is visual then the movie is raw and can be 
easily imported into software such as Octave and Matlab. After a few 
days of testing and swearing I was able to produce this videos using a 
second software called avi2raw (I'm running OS X abd Linux computers). 
Then a working procedure is like this:

         mencoder -ovc raw -oac copy -vf format=i420 -nuvopts raw:nolzo 
  -o output.avi input.mp4
         avi2raw output.avi final.yuv

As the learned reader may observe my YUV file is now a YUVi420 file - 
which is exactly what I want.

Well so far so good. PROBLEM IS I want to do the same thing starting 
out with a set of images (in tiff format).

Since my mencoder does not accept tiff I use TGA:

         convert -scale x576 -shave 336x0 img0001.tif 4cif_0001.tga

This way I get a tga image that could be part of a 4cif movie....

Then I try the following:

         mencoder mf:// -mf w=704:h=576:fps=24:type=tga -ovc raw -oac 
copy -vf format=i420 -nuvopts raw:nolzo -noframedrop -o output.avi

this avi can be played in so mplayer - however stripping of the AVI 
header and creating a YUVi420 seems impossible.

Could somebody tell me wether I have missed a big point here or give me 
some hints on how to proceede?




best regards
Ola Jetlund