Hi,
Here is a decoding speed comparison between new-trunk (theora-exp) and
old-trunk. I find out I missed some things last time so theora-exp
looked slower than it should be. The first thing is it is faster to
disable striped-decoding in dump_video.c. The second thing is the cpu
detection does not recognize the Geode used in OLPC so MMX was not
enabled. After fixing these two things, here are the numbers for some
clips I collected (svr r12867):
Athlon-XP Geode-GX
new old new/old new old new/old
320x240 320x240 462 800 0.57 63 88 0.71
322x242_not-divisibl 336x256 429 706 0.60 56 76 0.73
Building_On_The_Past 320x240 407 388 1.05 50 57 0.87
Elephants_Dream_1024 1024x576 51 36 1.42 7.9 7.5 1.05
Elephants_Dream_512- 512x288 216 155 1.39 29 29 1.00
MSD_ORACLE.vlog_2 368x240 511 457 1.12 68 79 0.86
chained_streams 320x240 462 750 0.61 61 83 0.73
monday_0930_Welcome 320x240 503 464 1.08 62 71 0.87
pixel_aspect_ratio 352x288 317 275 1.15 41 44 0.93
romalcc 352x288 503 657 0.76 76 103 0.73
timeskew1-t2s1 320x240 542 596 0.90 71 88 0.80
videotestsrc-720x576 720x576 89 148 0.60 15 21 0.71
The numbers are fps on Athlon-XP and Geode-GX. The new/old ratio is
the fps ratio between new-trunk and old-trunk. The result shows
new-trunk shines for larger resolutions, but for smaller resolutions
the old-trunk is faster (about 20% on Geode). I intended to do some
optimization for theora on OLPC, but now I am not sure which code base
should I work on...
The Geode MMX detection patch is attached.
Thanks,
Chih-Chung Chang
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Seems that latest revision include some more MMX optimizations. These are my
results using revision 12882. I am using a Dual Opteron 252 (2,6 GHz) on a 64
bit linux.
th-old : http://svn.xiph.org/trunk/theora-old/ compiled
with --disable-asm
th : http://svn.xiph.org/trunk/theora/ compiled
with --disable-asm
th-old-MMX : http://svn.xiph.org/trunk/theora-old/ (with MMX)
th-MMX : http://svn.xiph.org/trunk/theora/ (with MMX)
Times are in seconds, new/old is the speed ratio (higher, better).
frames th-old th new/old th-old-MMX th-MMX new/old
Romalcc 25178 12,75 15,02 0,85 11,44 12,74 0,9
Elep_1024 15293 167 144 1,16 131 113 1,16
Monday 55988 26,38 28,65 0,92 23,29 23,25 1
MSD_Oracl 42674 33,5 31,5 1,06 28,31 23,72 1,19
320x240 120 0,08 0,08 1 0,08 0,08 0,9
Videotest 49 0,12 0,22 0,54 0,12 0,2 0,61
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Seems also that, while using theora trunk, dump_video.c from theora-old is about 10% faster than dump_video.c from theora.> Seems that latest revision include some more MMX optimizations. These are my results using revision 12882. I am using a Dual Opteron 252 (2,6 GHz) on a 64 bit linux.------------------------------------------------------ Passa a Infostrada. ADSL e Telefono senza limiti e senza canone Telecom http://click.libero.it/infostrada