BeeJ said:
Win XP Pro with laptop and USB webcam.
Webcam res goes to 1080P.
Slow window webcam image update as expected due to limit of USB2 speed.
When recoding there are compression choices available.
1) For the standard Win XP Pro setup, what is the best video compression
to use?
Suggestions please.
2) is there other better add on compression available to install into
Win XP and what are they and where found?
Regular compression methods, are lossless (ZIP or 7Z or RAR).
They provide small amounts of compression, like say 3 times.
Video compression is generally lossy. But the compression is
around 100:1. And the methods rely on tricks that work with
the human eye. Lots of info can go missing, and the illusion
of a movie remains.
If the webcam is "dumb", the compression can be crude,
such as MJPEG. If you have a copy of UVCView, the config
section of the information sent by the camera, may contain
information on the compression methods available.
As for your statement about the webcam speed, there are
a couple of factors. Yes, the USB bus is a limitation.
But available light is another limitation - the camera
frame rate may be lower than expected, because there
isn't enough light, and modifying the frame rate
is a way to change the exposure.
*******
This gives the basics.
http://en.wikipedia.org/wiki/Video_compression#Video
And this is an example of a standard you could transcode to.
http://en.wikipedia.org/wiki/H.264
*******
This site has a wealth of information on video, and
the tools you can use.
http://www.videohelp.com
And if the menus aren't getting you anywhere, go to your
favorite search engine and try
site:videohelp.com mjpeg to H.264
and maybe you can find it that way.
*******
To identify the source video format, you can try GSpot.
There is one other media identification utility, but I
don't remember the name of it.
http://gspot.headbands.com/v26x/GSpot270a.zip
Paul
