[theora] Quality of vp3.2 codec?
FreunLaven at earthlink.net
Tue Nov 12 00:10:57 PST 2002
> Hope this helps
Actually it does.
Although I have a few questions about your tests.
<p><p>> If you do not know the difference between the format results you need
> some comparison tests then.
I don't have the resources to run a bunch of tests. And to be honest,
my old eyes are blurry enough that what's "good enough" for me is likely
to be considered poor by others. Just because I can force a codec to do
something doesn't mean I should...[grin]
<p>> I converted it to Quicktime using Sorensen and got a file about twice
> size 160MB at the same frame size as the MPEG 1
You cross converted the mpeg1 to quicktime, or did you start with the
Wouldn't the conversion from mpeg1 to quicktime add additional artifacts
and reduce the quality of the final video?
> I then ran the MPEG 1 through VP3 and got a file of 17MB
Same question as with Quicktime... Wouldn't the cross conversion effect
the final quality, resulting in a possibly higher bit rate for a
comparable level of quality?
Would you have gotten a better quality and/or slightly lower bit rate
requirement if you had used the original format?
(Of course, I do realize that most video will already be in mpeg1 or
mpeg2, so your conversion test is valid. I'm just curious.)
<p>> As to Reals Helix or Windows Media 9 or Divx 5.02 they all show far
> artifacting and have larger file sizes than VP3
I have to admit that I'm a little surprised by that. I don't know much
about Windoes Media 9 (and don't have much urge to!) but I was under the
impression that, according to the vp3 site, Real had long ago licenced
vp3 for their own player. So I would have expected Real to do *at
least* as well as vp3. (Of course, we still don't know if Real will
actually open up any of their codecs, like vp3 is.)
<p><p><p>--- >8 ----
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