[MPlayer-cvslog] CVS: main/libmpcodecs ve_lavc.c,1.113,1.114

[Rich Felker]

On Mon, May 09, 2005 at 12:12:37PM +0200, Michael Niedermayer wrote:
> Hi
> 
> On Monday 09 May 2005 05:12, Rich Felker wrote:
> > On Mon, May 09, 2005 at 03:07:42AM +0200, Michael Niedermayer wrote:
> [...]
> > > > > > Also colors didn't really look wrong to me (though my eyes (and
> > > > > > esp. LCD) aren't that good).
> > > > >
> > > > > well, tell this to the first user who notices that his lossless jpeg
> > > > > encodings look the same but arent
> > > >
> > > > They're lossless if you decode them with MPlayer/MEncoder, which also
> > > > assumes standard YUV colorspace when decoding jpeg..
> > >
> > > a bug in mplayer canceling out a bug in mencoder ...
> >
> > imo it's not a bug. conversion back and forth between standard yuv and
> > jpeg yuv is not lossless, so if you have a yuv image to begin with and
> > you want to compress it _losslessly_ with jpeg, the only way to do so
> > is to treat it as if it were jpeg colorspace even though it's not..
> >
> > the fact that the jpeg stream doesn't carry with it a tag for the
> > original colorspace is a loss of sorts, but as long as you keep your
> > files tagged properly it's not a problem.
> 
> with strict=-1 our jpeg decoder does store a user data/comment tag in the 
> stream about the colorspace, obviously that doesnt work if the wrong 
> colorspace info is given to lavc

Excellent. I didn't know it did that...now I agree totally with your
way of solving the problem.

Rich