[theora] A comparison of VP3, and two MPEG-4 variants

[Freun Laven]

Colin;

Very, VERY interesting.

I've wondered for a long time about the actual quality but never could
find any good information and didn't know how to do it myself.  And my
eyesight isn't good enough to be able to make decent subjective quality
testings.

I would, however, suggest expanding your tests.  Formats like:

1) mpeg-1  Yes, it's antique, but it's still often used because codecs
are readily available.  This would also show people how much smaller
files can really be, etc.

2) mpeg-2.  mpeg-4 always gets compared to it, but nobody ever really
says how much better it is etc.

3) The classic AVI codecs in Windows.  I know, I know... but people are
going to be curious.

4) The standard codecs in Quicktime.  The Apple people are going to be
interested.

5) Several compression levels of Windows Media and Real player.  One
version of Real's compression is based on VP3, so it would be
interesting to see a comparision.  I don't know which version, though.
Probably the G2, but I don't actually know.

6) And finally, it should be compared against XVid (which is opensource)
and *especially* DivX PRO 5.04.  (You could throw in the free version of
DivX, but I think the Pro might be more interesting.)

I realize that would take some time, but since you seem to have a way to
actually make the tests, so....

Finally, one last suggestions.... Could you use some other video clip?
Perhaps something that originates in digital video, rather than a mpeg2
format?  That might reduce any mpeg-2 compression artifacts to begin
with.  (And allow you to do a mpeg-2 comparison.)  And if you use some
other (non copyrighted) clip, perhaps you could talk the Theora people
into hosting / posting a few small video clips that actually show the
various qualities.  That way people can download it themselves and see
what it looks like.

I realize this is expanding a bit beyond your original tests, it's just
that for quite a while I've been looking for some decent tests that
actually compare video quality and you look like you might be able to do
relatively decent testing.

<p><p><p>--- >8 ----
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