Quality measurement on RV9

[bilu]

I started this thread instead of continuing the "Guides for RV9 encoding" thread ( http://forum.doom9.org/showthread.php?s=&threadid=63356 ) because I think this subject has a life on its own.

As said in the AutoRV9 guides the compressibility test is not a great measure. I'd like to see other opinions on that.

Also would like to hear about other forms of quality measurement in RV9.


Bilu

[bilu]

Found an answer:

http://forum.doom9.org/showthread.php?s=&postid=368971#post368971


Bilu

[bilu]

Compressibility test: 1st pass made at 75% VBRQuality, because can't get much better and gets about the same size as a 1st pass XVID encode, as reference. Tests have succeded at 55% but IMHO I would do at least 60%~65% on the comp. test . Only available on AutoRV9 for now.

MaxBitrate: 2.2 x AvgBitrate

Max startup latency: 60 sec

Max framerate: 30 fps

Max Keyframe interval: 10

EHQ level: recommended 80, I use 70 on a slow PC :)

65 = Default : improved efficiency for high action
70 = High : same as 65 + better mode decisions, better representation of high motion
80 = Extra High: same as 70 + best possible mode decisions, very high accuracy motion representation
50 = Fast : not recommended, use only for Live capture encoding

EHQ Encoding times:
65: same encoding time as before
70: will take about 2X - 2.5X encoding time compared to default
80: about 3X - 4X default


Undocumented parameters for Producer M6:

Pattern Adaptivity: default recommended, use patternAdaptivity=1 (or perhaps even 0) for animation content with less than full framerate, with or without using Dropdupe animation pre-filter;

Scaling Factor:
floatQP = prevQP * (1.0 + scalingFactor/100.0)

199 corresponds to ~3X
100 corresponds to ~2X
0 corresponds to ~1X

Pattern Adaptivity and Scaling Factor are equivalent concepts to XVID's number of b-frames and b-frame quant. ratio .

EDIT: default is recommended for both parameters.

Bilu