JimmyBarnes
10th June 2002, 13:13
The DivX Help Guide http://www.divx.com/support/divx/guide.php
states:
Note: RC settings are truly "for the adventurous souls". These default settings should give near optimum results.
RC Averaging
RC Averaging controls how fast the RC forgets the rate history. Larger values usually result in better higher motion scenes and worse low motion scenes."
While Gej's DivX Encoding Guidelines
http://www.divx.com/support/guides/guide.php?gid=1
state:
Data Rate Control (RC) parameters
First and very important, keep the Data Rate Control (RC) parameters to default value, the codec behavior has been tweaked around theses values: they are the "sweet spot" of the codec.
The only parameter you can safely change is RC averaging period, This represent the number of frame the RC algorithm will take in account to match the requested bitrate. Do not go under 100 frames even for shorter clip, the idea is to have the RC averaging period long as the half of the length of the clip you encode. The RC, specially in 2 pass mode, will allow more temporal variation of the bitrate and thus have a better handling of the fast motion scene.
The default RC Averaging Period is 2000 frames. Setting it to half the length of the clip to encode (say 50000-100000 or so frames) essentially negates any averaging at all, though I notice many seem to do just this.
I used this for the first time recently - RC av period of 73161 for an 98 min 25 fps movie. It may have resulted in some 5 or 6 split-second jerky frames which I have never seen before in 100 or so DivX TV viewings. Unfortunately I also used Ogg Vorbis audio/OGM for the first time in that same movie, so I am not quite sure what has happened.
Be interested in what ppl use for RC Averaging Period and what effects they believe it has.
thanx
JB
states:
Note: RC settings are truly "for the adventurous souls". These default settings should give near optimum results.
RC Averaging
RC Averaging controls how fast the RC forgets the rate history. Larger values usually result in better higher motion scenes and worse low motion scenes."
While Gej's DivX Encoding Guidelines
http://www.divx.com/support/guides/guide.php?gid=1
state:
Data Rate Control (RC) parameters
First and very important, keep the Data Rate Control (RC) parameters to default value, the codec behavior has been tweaked around theses values: they are the "sweet spot" of the codec.
The only parameter you can safely change is RC averaging period, This represent the number of frame the RC algorithm will take in account to match the requested bitrate. Do not go under 100 frames even for shorter clip, the idea is to have the RC averaging period long as the half of the length of the clip you encode. The RC, specially in 2 pass mode, will allow more temporal variation of the bitrate and thus have a better handling of the fast motion scene.
The default RC Averaging Period is 2000 frames. Setting it to half the length of the clip to encode (say 50000-100000 or so frames) essentially negates any averaging at all, though I notice many seem to do just this.
I used this for the first time recently - RC av period of 73161 for an 98 min 25 fps movie. It may have resulted in some 5 or 6 split-second jerky frames which I have never seen before in 100 or so DivX TV viewings. Unfortunately I also used Ogg Vorbis audio/OGM for the first time in that same movie, so I am not quite sure what has happened.
Be interested in what ppl use for RC Averaging Period and what effects they believe it has.
thanx
JB