example x264 commandline:
x264 --qp 24 --bframes 1 --ref 5 --8x8dct --subme 6 --trellis 2 --me umh --b-rdo --mixed-refs --direct spatial --no-b-adapt --keyint 999 --scenecut -1 foreman_352x288.yuv
(i.e. same bitstream features as JM used)
For the purpose of comparison, I disabled ratecontrol in both codecs (leaving constant QP), and disabled adaptive frame-type decision in x264.
The QPs tested are: 16, 20, 24, 28, 32, 36
All clips are approximately 250 frames, CIF resolution. In all plots, the better lines are the above options, and the worse lines are the same except with no B-frames and 1 reference.
Total encode time on an Athlon-XP 2500, for 24 videos * 6 bitrates * ~250 frames:
| with B-frames & refs | without | |
|---|---|---|
| JM | 202437 sec | 153032 sec |
| 5.817 sec/frame | 4.397 sec/frame | |
| x264 w/o trellis quantization |
4889 sec | 3047 sec |
| 0.1405 sec/frame | 0.0876 sec/frame | |
| x264 | 7748 sec | 6256 sec |
| 0.2226 sec/frame | 0.1798 sec/frame |
Average of all of the below
| Absolute rate vs distortion (higher is better) | Normalized (lower is better) |
|
|
akiyo
bridge-close
bus
coastguard
container
flower
football
foreman
hall
highway
mobile
mother_daughter
news
paris
silent
stefan
tempete
tennis
waterfall
Etorofu
Exile
Haibane
Hpii
Shell
