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malikcis
14th December 2011, 11:51
Where can I find a benchmark report of the h264 tools?
for example:
cabac: 10% bitrate saving
1/4 pel search: 5% bitrate saving
loop filter: ...
etc...

nurbs
14th December 2011, 12:50
For CABAC vs. CAVLC there are these:
http://akuvian.org/src/x264/entropy.png
http://akuvian.org/src/x264/entropy_avg.png

malikcis
14th December 2011, 15:00
This is very interesting. I did not know CABAC is better for higher quantizers.
Any idea where to find more such benchmarks?

imcold
15th December 2011, 21:36
In reports from JVT meetings from before h.264 final drafts, for example; each option was evaluated before being added to the standard, afaik.

Shevach
26th December 2011, 09:26
Almost in all cases CABAC is better than CAVLC.
I am aware only one extreme case when CAVLC is slightely better than CABAC.
If you encode all MBs in a picture as skip MBs then CAVLC encoding provides less bits than CABAC one.

nm
26th December 2011, 20:20
Almost in all cases CABAC is better than CAVLC.

No question about that. Malikcis commented on the graph that shows ~8 % bitrate difference in favour of CABAC at low QPs, increasing to ~20 % at QP 30, and higher as QP rises.