[MPlayer-dev-eng] [PATCH] mencoder : set output image quality = input image quality

[Michael Niedermayer]

Hi

On Monday 18 November 2002 21:41, Christophe Gouiran wrote:
> Hi MPlayer developpers, I made modification to mencoder in order to achieve
> the same effect option -sameq for ffmpeg do : it tries as much as it can to
> do a lossless compression of source video. I think this feature was missing
> from mencoder.
>
> Now switch -lavcopts accept a new parameter :sameq
> To works, source must be decoded by a codec from libavcodec (this is
> checked and option is disabled if it's not the case) because as far as I
> know those codecs are the only one that determine the "quality" of the
> input video.
>
> Of course this patch is applicable against the current cvs version (Monday
> november 18 2002).
>
> I'd be glad to have some feedback on this patch, feel free to contact me.
hmm, passing the quality as a global variable is IMHO not the best choice, 
even though it works, 
and "if (strcmp(sh_video->codec->drv, "ffmpeg"))" in ve_lavc.c is allso not a 
very clean way of checking for quality-decoding support

IMHO, we should pass the quality as a parameter of mp_image_t, well actually 
we allready do, its in mpi->qscale, this is an array of qualities for each 
macroblock (16x16 pixel) we should average these and use it as quality for 
encoding with -sameq, this would allso work with libmpeg2 as decoder

[...]

Michael