>     I think it is the second half of this statement that is the crux. I
mad
> a few more objects and it seems to work much better without dropping the
> bitrate.

That is because more movement creates more for the MPEG to encode, so the
buffer does not underrun. When I first started encoding I thought that a
352x240 sized animation should get about 1.8 Mbits/s and then say 176x120
might need about 450kbits/s, and so on, and I could derive the needed
bitrate like that, but what I found is those numbers only work for
full-motion or very-near-full-motion. When I had an animation with very
little motion I needed to drop the bitrate a lot to keep from screwing it up
and making an unplayable file. Sometimes when it only screws up a little I
notice the play timer is WAY off, when it gets a lot of underruns Media
Player just chops it up. I won't say its Media Player's fault because I'm
pretty sure the MPEG's are going out of spec, but I also don't think its the
encoder's fault because it's just encoding with the parameters given (but it
should tell you that's its blown the buffer, and that it might not play
right).

I'm sure there's others around here that could explain this better because
I'm far from knowing what I'm talking about. But like I said before, finding
the right bitrate seems to be trial and error. I wish I could find some
program that I could run my animation through first, and it would return the
best bitrate, the sweet-spot so to speak, but I have yet to find it.

Enough of me blabbering, if you've encoded something, and now you find out
that it doesn't play right AND you've deleted the originals, you can get all
the unplayable data back by pushing it through VirtualDub. The program is a
free AVI mutilator, and there's lots of good stuff I could say about but
just go to http://www.geocities.com/virtualdub and see for yourself.  The
source is there too (one day I plan on shoving mpeg2encode into it, but
since I patched* MP+ to output MPEGs I don't need it that urgently anymore).


*I don't really plan to release though, it seems all I got was negative
feedback when I asked about it before.




Jeff

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