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Linux Real Time MPEG Compression?
aszoth asks: "I working on a project that is going to require approximately 4 hours of video recording per day for about two months. We are currently using DVM tapes, however the extraction and compression time has left us with a large library of tapes un-converted. We are considering other methods, in particular real time MPEG 2 or MPEG 4 Compression. We also would like to be able to slow down our frame rate from the 29.7 fps to something along the lines of 5-15 fps. I am wondering if any one has any suggestions on possible ways to do such compression (or get similar results) with a Linux box. Thank you for any help you can give."
mpeg4ip should do what you want, if you are willing to ignore the issues with licensing of the MPEG-4 patent portfolio.
If you are not stuck with Linux, I would suggest using a mac - Quick Time Broadcaster does real time mpeg4 encoding at good quality even on old iBooks, and the mpeg-4 royalties are taken of as part of the cost of QuickTime Pro.
MJPEG (Motion JPEG)?
My opinions may have changed, but not the fact that I am right! =)
if you have a dedicated powerhouse (~1.5 GHz+) then you might be able to do Realtime encoding under linux. But many ppl (including myself) have experienced A/V sync problems with FFMPEG...
If you have anything less than a dedicated 2GHz machine, you should seriously look into a hardware encoder.
Canopus makes some cheap mpeg encoder cards, but it looks like the Linux support is sparse...the WinTV PVR-250 is fairly cheap ($150) and supports both MPEG1 & MPEG2 encoding.
So...why bother with something that *MIGHT* work and go with something that is certain to work...
In all fairness, some of the AV sync problems with ffmpeg are most likely due to a difference between the buffer sizes of the video and audio...
It's a great compliment to the community that people can ask a question assuming there will be an informed, helpful response. The knee-jerk "google it" reaction that is so common these days is tearing apart this vital facet of the community.
Still, it is prudent to do your Google homework before posting to any online forum. This keeps the signal-to-noise ratio up and makes people feel it's worth to come back to the site later.
Actually, the knee-jerk RTFM/RTFGoogle answers you're witnessing are all about community! More specifically, about teaching people how to behave here at Ask Slashdot. Saying "search Google before posting to Ask Slashdot" is very much like saying "don't shout in the library".
--Bud