Ako din medyo nalilito sa MP4, DivX, .avi formats.
who knows?
aside from being a video codec, DivX is a commercial implementation of MPEG4 Part 2 Advanced Simple Profile spec. and so is Xvid while being an open-source alternative implementation.
so maybe when we see an MPEG4 player, it could mean that it
unofficially supports DivX and/or Xvid.
(no wonder some MPEG4 players have divx/xvid playback bugs).
and when we see a DivX-certificed player, it means it will
officially play DivX problem-free at some level. Xvid is another matter as it may or may not work. DivX certifies only Divx. it does not include Xvid certification. (no wonder some official divx players have flaky xvid support)
AVI is a file format. a way to put video, audio, subtitle data into one file. i'm not sure but i think it has nothing to do with MPEG4 spec at all. it's just the most well-known way of putting a divx file together so it became the defacto standard in standalone players.
the real official MPEG4 file format is something similar to the QuikTime file format. i have a couple of them, but i have not tried them on my divx player as i doubt it can even decode the file even if it understands divx/xvid.
and the real official MPEG4 video/audio codecs are H.264/AVC and AAC. and i doubt that my player will play these files with these encodes.
so MPEG4/DivX players are probably named so because they can play divx/xvid AVI files, and not because they can decode the real MPEG4 file format or even play real AVC/AAC video/audio streams (though i wish they'd do so)