[MEncoder-users] help with creating avi from jpegs

[Joey Parrish]

On 5/16/07, Lee Birch <birch.lee at gmail.com> wrote:
> 1) WIndows Media Player (not my choice)
> 2) No file size limitation, I believe.  Smaller is better because I have to
> distribute some of them across a network.  My test files have only been a
> minute long - but I could see 10-15 minute videos.
> 3) Yes, I could have a master video and a distributable video.  I did not
> anticipate keeping the PNG files around forever, however.  You could
> convince me otherwise.
>
> I have used "vcodec=msmpeg4v2" with lavc.  It seems to work seemlessly for
> my audience.  I'm concerned about this codec.  Should I be avoiding it and
> using something else?

No.  If it works for your audience, perfect.  That's what matters.

Now, if you encode to msmpeg4v2, you cannot append to that without a
loss of quality.  That's because "append" for mencoder means decode
old video + new frame, encode the lot of them as one stream.  So, your
options are these:

1) Keep png's forever, encode them all to msmpeg4v2 when a new one is added.
2) Add new png's to an uncompressed mpng avi, then transcode it to
msmpeg4v2 for distribution.

Option #1: Faster (one encoding step instead of two.)
Option #2: Allows you to trash old pngs, but the avi containing them
is in fact larger than the collection of png's would be alone.

Either way, you have to encode something to msmpeg4v2.  So we should
look at your options for this step and find the best setup.  What
command-line have you successfully used before to create good
msmpeg4v2, and what aspect of it's output would you like to improve?

--Joey