[theora] Quality of vp3.2 codec?

Colin Mckellar c.mckellar at student.murdoch.edu.au
Tue Nov 12 00:06:10 PST 2002



Bitrate and quality are fairly closely related... when you compare 
codecs, you have to look at them together.

When I think of codecs, I generally separate them into different "eras" 
Within an "era" codecs generally have a similar quality:size ratio, and 
similar playback requirements. Between eras, the quality:size 
difference becomes much much more significant. I consider MPEG1 and 
MPEG2 to be in an era together with Sorenson 2, and perhaps Indeo 5 (I 
have not tested indeo 5 very much). VP3 lies together with divx, WM9, 
MPEG-4, Zygovideo etc... anyway, to cut a long story short, I consider 
them to be largely equivalent in quality:size to those other codecs.

As to specific performance, I have been using VP3 for about 2 years. I 
spend a lot of time testing out different codecs. I generally re-encode 
DVDs, and try to fit them onto a CD. (Note: about 90% of the DVDs that 
I rip I own. I end rip each DVD about 4-10 times, testing out different 
codecs and settings... I am more interested in playing around with 
codecs than with copying movies)... I use the quicktime component, and 
it doesn't have the flexibility that it could.... for example, you 
can't encode at a constant quality... it is only quasi-CBR, so the 
quality of Theora should be better... anyway, in my experience, VP3 can 
reproduce low action scenes with amazingly high quality, at very low 
bitrates (I consider 50-60KB/s to be low bitrates for 640x272). Where 
VP3 does fall down, however, is with scenes with fairly high action. 
VP3 does not give enough data to the scenes with high action, so it 
gets very blocky very quickly (it produces 8x8 blocks of solid 
colour).. even so, most codecs have trouble with high action scenes, 
and, for the most part, it is not too bad.
Generally, I prefer VP3 to pretty much every other codec that is widely 
available, except in certain high motion scenes.

Blibbler

On Tuesday, November 12, 2002, at 01:03  PM, Freun Laven wrote:

> How good is the video compression in vp3.2?
>
> For example, how does it compare (bit rate & quality) to mpeg1, mpeg2,
> Divx, real Video 8+, Windows Media, etc. etc.
>
> It being open source is nice and all, but if it can't be reasonably
> competitive then there isn't much point to it.
>
> I just haven't seen anything that compares vp32 to anything else.
> (Although to be honest, I haven't seen much on honest comparisons of 
> the
> other formats, either.)
>
>
>
>
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