Dick Balaska <dic### [at] buckosoftcom> wrote:
: "I then pass that through VirtualDub using the Microsoft MPEG-4 Video Codec V2"

: Maybe that sentence was unclear.  I did mean "through the VirtualDub stream filter
: system".  To be combatant about it ;O it *is* VirtualDub which encodes the stream.
: The codecs just supply a filter specific to a type of stream.

  No, VirtualDub just asks the codec to encode the stream. VirtualDub does
not encode it itself (it just gives data to the codec and then stores the
data returned by the codec to a file).

: Actually, as i said, i have a top quality MPEG-1.  It is unplayable because
: the bitrate is way too high.  But i can look at individual frames and they
: are pretty dang close to the original PNGs.  

  I personally would not make the in-between MPEG-1 step, no matter how high
quality it would be. It's perfectly possible to make an AVI with the raw frames
and encode that to some MPEG4 format, so why not do that? You minimize the loss
of data.

: Is it not true that MPEG-2 is son of MPEG-1 with some new fangled compression
: algorithms?  I believe it was one of the Berkeley boys that said something to 
: the effect of "When we were researching codecs for the new HDTV format, we were 
: surprised that MPEG-1 was designed robust enough that it just scaled up and 
: thus it became the basis for the new MPEG-2 format".

  MPEG-1 may be good as a streaming format, but the video compression algorithm
it uses is not very good (in today's standards). It compresses too little with
too much loss of quality.

: POV-Ray makes beautiful delicate shadows on the wall which MPEG-1 preserves
: pretty well.  All of the AVI codecs i've tried turn that beige/white wall
: and it's shadows into fractalized blocky things.

  What quality settings did you use? If you use some 120 kbps bitrate for
the video, no wonder why you get such an awful result.
  At about 2000 kbps the MPEG4 video should be almost perfect (although it's
a bit bloated in file size; usually something like 500 kbps is a good
compromise). With DivX you can go up to something like 6000 kbps.

  I have encoded lots and lots of DivX AVIs. I have some experience.

-- 
#macro N(D)#if(D>99)cylinder{M()#local D=div(D,104);M().5,2pigment{rgb M()}}
N(D)#end#end#macro M()<mod(D,13)-6mod(div(D,13)8)-3,10>#end blob{
N(11117333955)N(4254934330)N(3900569407)N(7382340)N(3358)N(970)}//  - Warp -

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