On Tue, 21 Sep 2004 17:25:00 +0800 Derek Fountain <[EMAIL PROTECTED]> wrote:
> While I'm asking, here's another quick question: can I do anything > with the sound to lower the file size? It's just crowd noise and > commentary so I can drop the quality right down if that's possible. > I was just trying to work out what lav2yuv actually does with the > sound. My command: > > lav2yuv ... | mencoder -oac copy ... > > appears to be giving me MP3 sound, which implies lav2yuv puts out an > MP3 sound track. Is that right, and can I tune it? lav2yuv puts out no sound. lav2wav outputs pcm which is encoded to mp3 and stashed in frameno.avi in the 1st phase of lav2avi.sh. You could add options to this phase to reduce the mp3 bitrate. The best way to reduce the size of the sound is to encode to vorbis instead of mp3 but this means you can't use avi you must use mkv or ogm instead. This in turn means that to play on Windows you would need to install special dshow filters and codecs. I regularly record talk radio to ogg vorbis. Using -q -1 and resampling to 22050 samples/s takes up ~14MB per hour. This would allow you a video bitrate of ~430kb/s for an hour of video in 200MB. That's going to look pretty bad but may be acceptable to you. Get oggtools and mkvtools. Replace the 1st phase of the script with just encoding the sound to ogg. After the 3rd phase mux the ogg with the avi using mkvmerge to create an mkv file. The script has no options to improve the video quality. You should at least use mbd=2. I would also recommend mv0:cbp:trell:keyint=125:naq:v4mv:vratetol=32000 but all this will increase encoding time a lot. Martin ------------------------------------------------------- This SF.Net email is sponsored by: YOU BE THE JUDGE. Be one of 170 Project Admins to receive an Apple iPod Mini FREE for your judgement on who ports your project to Linux PPC the best. Sponsored by IBM. Deadline: Sept. 24. Go here: http://sf.net/ppc_contest.php _______________________________________________ Mjpeg-users mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/mjpeg-users
