impact of x264 options on _decoding_ speed|complexity

[taeuber]

Hi there,

I'm interested to encode videos with a certain quality (crf) but with a focus on decoding speed (decoding complexity).

Therefore it's good to know which options (or at least which non standard options) have a positive or negative impact on the decoding speed while reducing resulting file size.
In other words: which options that enhance quality or reduce file size at same quality have which effect during decoding.

Software CPU-only decoders (non GPU supported decoders) are of interest. I know it also depends on the implementation but think about a »theorecially optimal« decoder or ffmpeg on x86_64 cpus.

Impact in speed also could be distinguish between memory bandwidth or instruction cycles.

Thanks a lot
Lars

[nurbs]

Try this: http://forum.doom9.org/showthread.php?t=147263

[LoRd_MuldeR]

CABAC gives you ~15% (http://akuvian.org/src/x264/entropy.png) extra compression and is absolutely lossless, but it's expensive to decode.

It's known that CABAC can easily become the performance bottleneck for decoding H.264.

Note that the CPU time required for CABAC decoding highly depends on the bitrate of the video...

[nm]

Also:
http://forum.doom9.org/showthread.php?t=122761
http://forum.doom9.org/showthread.php?t=99402

[taeuber]

Many thanks!

I just used the wrong words for the search.

Lars