[MPlayer-users] Re: spurious blockiness when transcoding high-bitrate mpeg2 to med-bitrate mpeg4

[rcooley]

On Sat, 03 Jul 2004 22:08:50 +0200
Simen Thoresen <simentt at dolphinics.no> wrote:

> I've been using the Windows-player 'Media Player classic' with the
> K-Lite build of XviD as my player, so I now checked with the mplayer
> build I have on my RH8 box (also 1.0Pre3), and here I see no problems
> at all - on none of my encodes. 

Well, there's your problem.  Look no further.  You would have saved
several people a lot of time if you had mentioned that little fact.

> So - either mencoder produces 'odd' mpeg4 AVIs, or lavcs mpeg4-codec
> is more tolerant than the one I've installed on my windows-box.

No, neither.  What you've got is likely an incompatibility between the
codecs.  In fact, all the advice you've recieved on this list will just
make this problem worse, not better.  Lavc is probably using MPEG-4
options that your Xvid codec just doesn't understand.  Stick with just
"mbd=2:trell:bitrate=" in your lavcopts, and you'll have something that
is compatible with the most primitive codecs (including hardware
players).  B-frames are a big no-no, as is v4mv and qpel.  If you use
them to encode, you must playback only with a codec that also
understands them.  

This is all assuming your MPEG-4 codec isn't completely hosed.  Can you
successfully play-back any MPEG-4 material (encoded with something
other than Mencoder)? If not, it's not because the video is just
poor quality, it's because your media player, MPEG-4 codec, or OS is
screwed up, badly.