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Razorblade2000
26th August 2004, 12:00
Hmmm... I just wonder... should I try CBR Mode?

My thought is, that anytime I raise the bitrate using the ratecontrol of a VBR Mode, I'll have to go down with the bitrate at another point.
As I encode at a, for a movie, REALLY low bitrate, I can't go down much more because it will instantly start looking crappy sad.gif

One solution for this is setting the maximum bitrate very close to the minimum bitrate... but will this change quality for high motion parts that much? (If yes, it will make it worse for other parts, will it?)

If I use CBR, our Bitrate won't really change in high or slow motion scenes, but the encoding process should be way faster biggrin.gif

p.s.
These 350k are targeted on local file playback with a 480*X Resolution
Sirber
26th August 2004, 13:34
You ARE mad :p

I would try VBR 2-pass, streaming, 2x max bitrate, dropdupe.

Good luck :)
Razorblade2000
26th August 2004, 13:48
350k works fine :)

it actually looks pretty good... i just want it to look better :D
Sirber
26th August 2004, 14:02
What about CQ40?
Razorblade2000
27th August 2004, 00:27
CQ Mode without prediction is just too certain to go wrong in the end size :D

CQ 60 gives me in my current testings a 300k avg bitrate :-)
(and it's looking good)

Maybe I'll fresh up my delphi knowledge and try to implement prediction

(it shouldn't be that difficult...
1. add the http://www.avisynth.org/SelectEvery command to the anime.avs
2. encode this short (5 minutes should be ok) sample with cq 80
3. check the filesize of the resulting rmvb
4. Based on the Length of the sample and its size, you can calculate an avg bitrage of the sample
5. If samplesize > wanted samplesize---> lower CQ by 10 ---> encode again with new cq
6. do this again until samplesize < wanted samplesize ---> raise cq by 1 (or 2)
7. encode the sample again till samplesize is again > wanted samplesize
8. voilá, you've got your CQ Value :D

something like that...
Sirber
27th August 2004, 00:32
If you succeed in this, it will be my pleasure to steal your source and add it to realanime :D. I'm currently working on VFW implementation.
Sagittaire
29th August 2004, 03:05
Use Old RC for very low bitrate ...
Sirber
29th August 2004, 03:10
Yep, that's what I called "streaming". :) New RC kill low bitrate scenes at low bitrate :(