On Wed, 29 Dec 2004, Ray Cole wrote: Hi!
> I've encoded several things since successfully compiling from CVS last week > and it seems to me the quality has noticeably improved. I originally built Do a cvs update and rebuild now - changes since last week might get a (tiny) fraction more quality ;) > from CVS wanting to try y4mdenoise, but it is just too slow for me to use. It does want a 2+GHz cpu doesn't it? I had one run on a 2GHz G5 that went about 25 hours. Came out looking beautiful. I think things will look better and run faster when I switch from the ADVC100 to the -300 which can do some denoising on the signal as it's being digitized. > However I do use y4mspatialfilter right before yuvdenoise, so my chain is > {raw video} -> yuvscaler -> yuvcorrect -> y4mspatialfilter -> yuvycsnoise -> > yuvdenoise -> mpeg2enc. ..short chain :-) Hmmm, the 'yuvycsnoise' filter could probably be dropped - even when I was using a Bt878 card that filter didn't seem to make any difference (for better or for worse). If you're capturing at full frame square pixel (which for a Bt878 is 640x480) then you are scaling/resampling to 704x480 and not 720x480 I hope. If the latter then the aspect ratio is being distorted about 2%. Full frame broadcast TV (and VHS tapes, etc) in the US are 704x480 with 10:11 pixels. This, as arithmetic will show is a 4/3 image equivalent to 640x480 with 1:1 pixels. > Anyway, it appears to me the quality is a little better than before (ie - last > official release). Edges seem to be very crisp now. I'm not sure if that is Glad to hear that the last year of development hasn't been a complete waste of time :-) :-) > from improvements in yuvdenoise, the addition of y4mspatialfilter, improvement > to mpeg2enc, or some combination :-) "All of the above" <grin>. y4mspatialfilter didn't exist in the last "official release" as I recall though. > y4mspatialfilter's defaults caused the image to blur really bad, but I was > able to tweak the parameters to it to get some good results. I get a slightly Hmmm - interesting. For capturing from VHS tapes the defaults are fairy moderate (-L 4,0.75,4,0.75 -C 4,0.6,4,0.6). For laser discs I bumped up the 0.75 to 0.8. The -C (chroma) values are definitely over-conservative (0.5 would probably have been better) since VHS has only about 1/2 the chroma bandwidth that broadcast TV has. > lower bitrate using y4mspatialfilter, but keep it before yuvdenoise because > if I place it after yuvdenoise it tends to blur a little. Seems like > yuvdenoise runs faster than it used to as well, though I've not done any It does. Stefan and others put effort into speeding it up - nice to hear that the improvements are noticeable. Cheers, Steven Schultz ------------------------------------------------------- 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