[FFmpeg-devel] [RFC/PATCH] bitpacked_dec: Optimization for bitpacked_dec decoder performance

[Devin Heitmueller]

On Sat, May 6, 2023 at 8:16 AM James Almer <jamrial at gmail.com> wrote:
> Can you bench with the START_TIMER and STOP_TIMER macros in timer.h?
> Also, define CACHED_BITSTREAM_READER in bitpacked_dec.c before including
> git_bits.h and test the actual implementation again, to see if it makes
> any difference.

Original code:
671661910 decicycles in bitpacked_dec,       1 runs,      0 skips
669736380 decicycles in bitpacked_dec,       1 runs,      0 skips
669370700 decicycles in bitpacked_dec,       1 runs,      0 skips

Original code with CACHED_BITSTREAM_READER defined
352599030 decicycles in bitpacked_dec,       1 runs,      0 skips
336163810 decicycles in bitpacked_dec,       1 runs,      0 skips
344628350 decicycles in bitpacked_dec,       1 runs,      0 skips

My proposed versioned:
257353330 decicycles in bitpacked_dec,       1 runs,      0 skips
271527000 decicycles in bitpacked_dec,       1 runs,      0 skips
252701500 decicycles in bitpacked_dec,       1 runs,      0 skips

Devin

-- 
Devin Heitmueller, Senior Software Engineer
LTN Global Communications
o: +1 (301) 363-1001
w: https://ltnglobal.com  e: devin.heitmueller at ltnglobal.com
-------------- next part --------------
A non-text attachment was scrubbed...
Name: timing3.patch
Type: application/octet-stream
Size: 1116 bytes
Desc: not available
URL: <https://ffmpeg.org/pipermail/ffmpeg-devel/attachments/20230506/f35bc00b/attachment.obj>