[MPlayer-users] Re: Mpeg2 encoding results

[Jonathan Rogers]

Nico wrote:
> Well, the quality was very good, but both movies showed the usual 
> problem that I find in every lavc encoding (mpeg1/2/4):
> black areas show many visible greyish blocks, at least when read from a 
> DVD player.

Just out of curiosity, have you found an MPEG-4 encoder that doesn't 
have this problem as much at the same BPP? I haven't noticed XviD or 
DivX doing much better, but maybe I just haven't looked closely enough. 
Maybe lavc doesn't scale up to high bitrates as well as other encoders?

> Mplayer is so good at decoding that it  deceives the eyes, showing a 
> good picture (blocks show less) even when it's bad :)

It seems to be somewhat accepted that video quality is a function of 
both the encoder and decoder, though there is clearly more of challenge 
in the encoding. Maybe it's that MPEG-4 gives much more freedom for the 
decoder to enhance quality than MPEG-2 and the lavc encoder and decoder 
are essentially MPEG-4 encoders, even in MPEG-2 mode. Or, perhaps DVDs 
allow for such high bitrates that they don't typically need good 
decoders to get good results.

Jonathan Rogers