[x264-devel] ”ultrafast“ preset preformance decrases after commit "Unify 8-bit and 10-bit CLI and libraries"

[wangguan (D)]

Hi, all

After the commit “Unify 8-bit and 10-bit CLI and libraries"(http://git.videolan.org/gitweb.cgi?p=x264.git;a=commit;h=71ed44c7312438fac7c5c5301e45522e57127db4), the “ultrafast” preset costs more time encoding.
The commit “Unify 8-bit and 10-bit CLI and libraries" moves the function param_apply_preset from common/common.c to common/base.c , and also change the content of param_apply_preset.
Before the commit, in common/common.c, the old version param_apply_preset sets “param->analyse.i_trellis = 0;” if preset is ultrafast
After the commit, in common/base.c, the new version param_apply_preset  misses to set “param->analyse.i_trellis = 0;” if preset is ultrafast.

I think it’s a bug, i_trellis’s default value is 2, and i_trellis is set to 0 in “superfast” and “veryfast”.  So it makes no sense for i_trellis to be 2 in “ultrafast”.
Fixing this can restore the performance in “ultrafast” preset.

Thank you.
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