--- Ray Cole <[EMAIL PROTECTED]> wrote: > I originally built > from CVS wanting to try y4mdenoise, but it is just > too slow for me to use.
yuvdenoise and y4mdenoise, completely separate from algorithmic differences, have one very important difference right off the bat. yuvdenoise analyzes the new frame in terms of non-overlapping 8x8 blocks. y4mdenoise analyzes the new frame in terms of overlapping 4x2 blocks (for intensity) and 2x2 blocks (for color), and all matches are flood-filled to extend them to pixel accuracy before applying them. >From that point of view, y4mdenoise should be 15x to 60x slower than yuvdenoise, but instead (the last I heard) it's about 3x slower, despite all the extra work it's doing. Keep that in mind when you say it's slow. Also, yuvdenoise has an artifact that leaves traces of previous frames behind in new frames. You see this especially in fade-outs, where an afterimage is left behind in the "blank" screen. You also see this in after-movie credits against a black background; the black left behind by moving credits is a different color than the black in the rest of the image. Use yuvdenoise if you want to remove most of the noise from your video stream. y4mdenoise is more of an image-reconstructor than a denoiser, really. It tends to make VHS videotapes look like LaserDiscs. I think it even has forensic applications, e.g. one could run security-camera video through it to bring out details in perpetrators' faces. I recently got access to a dual-processor machine, and so now I can implement and test a multi-processor-aware version of y4mdenoise. Since it naturally processes intensity separately from color, I can do them in parallel; that should be an easy change to write. I can also process different parts of the frame in parallel, but that will be much more difficult to write. So if you've got a multi-processor computer, you may get some relief soon. Steven Boswell ulatekh at yahoo dot com __________________________________ Do you Yahoo!? Send holiday email and support a worthy cause. Do good. http://celebrity.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