real differences between divx3 amp; divx5 codecs

andy

Hi everybody,
I've recently watched an anime encoded with divx3 (I usually use divx5), and I've been really amazed by the quality of the avi. So I'm wondering if ther's a specific codec for each kind of source movie or if the new developpement of standard codec (like divx5) really improved the quality of the avi instead of the older one?

It's a different codec.  DivX 3.x is an MPEG-4-based codec created by Microsoft - they changed several things about the MPEG-4 standard (motion vector storage and VLC coding in particular).  The VLC changes allow for more compact storage of the same data from what I've seen, and the encoder they created uses a block-skipping threshold to cut bitrate significantly (though this has the side-effect of smearing, which I'm sure everyone is familiar with).

DivX 4/5 is an implementation of MPEG-4 from the spec itself, without extra alterations.  This may hinder it in some areas that Microsoft's codec worked well in, but has the advantage of being a standard.

-h

which codec, div3, div5 or Xvid offers the best compressibility:quality ratio?

Good question! According to what I've read in many threads it seems Divx5 is the best, even if in my opinion Xvid gives really great results.

Unfortunately quot;qualityquot; is a subjective parameter - there isn't really a dependable way you can compress a video with a bunch of different codecs, run it through a quot;quality measuring programquot; and have it spit out a number that you can compare to the others.

The only way to test this is to compress a sequence at a given bitrate, then see which codec looks the best.

-h

Look at Doom9's Codec Comparison, plz recognize that the XviD version used is pretty old, for low bitrate encodes you can also try Windows Media 9 with Nic's WM9 Encoder