film grain

[yokotsoko]

I have this film with heavy grain. ( I mean it is like a handicam shot with inadequate luminance and too much grain all over the picture)
I think that I'm asking much but might there be a virtualdub filter for smoothing this effect?

[Fox Mulder]

http://sauron.mordor.net/dgraft/

[theReal]

also try convolution3d. It's an avisynth filter with amazing effects for compressibility. Then, you can always use Divx 5's pre-processing - it's also a pretty good noise-reduction.

[yokotsoko]

about convolution3d. You said that it compresses better the picture if I understood right. Why should this help for noise reduction?
about pre-processing. I don't remember exactly but I think that I read somewhere in the forum that pre-processing is still buggy or/and it causes jerky playback. Anyway I had the impression not to use it.Am I wrong or maybe light pre processing may actually be good? In fact many of the DivX movies I encode, I play in my p2@350Mhz, so the decoding power the movie needs, concerns me.

[theReal]

You said that it compresses better the picture if I understood right. Why should this help for noise reduction?The other way round: it reduces noise, so the movie will compress better. To say it correctly, convolution3d is a very effective noise reduction filter :)

The pre-processing in Divx5 has never had any bugs, I think. I've been using it since Divx 5.0 and never had a problem. It doesn't make the post-processing any more difficult for the cpu because it's just a noise-reduction filter.

I guess you were thinking of psychovisual enhancements which were buggy until the last release (now you can use them, but don't really need to - doesn't make a big difference). Also, don't use Quarter-Pel because it uses much more cpu power on playback. For playback on a P2-350, also better don't use GMC (maybe not even b-frames, however I'd try to use b-frames and see if the playback is ok on the old processor - you loose much compressibility by not using b-frames).

btw. if you're also encoding on that P2-350, you're not going to be happy with convolution3d - then the Divx pre-processing will probably be your only chance to get a movie done before next christmas ;)

[yokotsoko]

Ok p2@350 may not be the best hardware to use.Anyway I don't have any problems at playing DivX. I encode (luckily on another computer :) )using divX 5.02, B-frames and mp3 sound. The playback using my p2 has no async problems (post processing level is set to none of course).
Anyway there is something more I would like to know.
Should I use light pre processing or go straight to strong?

[theReal]

For my taste, strong pre-processing is a little too strong (the picture gets blurred too much). I use light or normal for TV-captures. Usually I try to leave it at light and use another filter before (one that removes noise without blurring, like Temporalsmoother or convolution3d) and see if that is enough. Normal already blurs quite a bit.

Just try it and you'll see...