Oops, I forgot to discuss the non-denoising- related aspects of the way I use mpeg2enc! :-)
The first mpeg2enc in the script file generates a DVD. "-b 9300" is the highest I go in practice; that allows for 384 kbps audio and (my estimate) 120 kbps for the information mplex adds, staying under the limit of 9800 kbps for DVDs. "-D 10" does something to increase the resolution. I don't totally understand it. I don't know if I saw a difference. But it's supposed to work. "-H" selects the high-quality quantizing matrix. The other developers told me I was nuts for using it, since it'd wildly increase the bitrate needed to encode my video. But y4mdenoise seems to do a lot of good for the bitrate. One video I did recently needed an average bitrate of 5050 kbps to fit on a DVD, but -q 3 got away with -b 5500 and -q 4 got away with -b 7500. Another recent video needed an average 6450 kbps for the video, but -q 3 took -b 9300 and still had space left over on the DVD. And -H gets rid of artifacts I see with the other quantizing matrices; the most obvious one is stair-steppy artifacts along slanted transitions between very light areas and very dark areas. So I say use -H! "-4 1 -2 1" makes mpeg2enc spend as much time as possible detecting motion. Most of the compression possible with video is based around the idea that any parts of the new frame that you can copy from the previous frame saves you the space needed to explicitly describe those areas. The problem is, the areas need to be _numerically_ equal, not just "look close enough" -- mpeg2enc doesn't know what that is. y4mdenoise is my answer to how to tell a computer what "close enough" looks like, and it seems to do a pretty good job. Therefore, I think any extra time spent by mpeg2enc detecting parts of the new frame that are moved instances of parts of the previous frame is a Good Thing, and so I use the highest setting possible for -4 and -2. The rest of the options are not related to denoising or quality, just DVD format. Steven Boswell ulatekh at yahoo dot com __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com ------------------------------------------------------- The SF.Net email is sponsored by: Beat the post-holiday blues Get a FREE limited edition SourceForge.net t-shirt from ThinkGeek. It's fun and FREE -- well, almost....http://www.thinkgeek.com/sfshirt _______________________________________________ Mjpeg-users mailing list Mjpeg-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/mjpeg-users
