[bstar77]

My hypothesis for the performance disparity is that h264 encoding is hardware accelerated and webm is not.

[wolf550e]

x264 does not use GPU hardware, so they're both using just the CPU. WebM fails to use more threads or 256bit or 128bit registers correctly.

[1ris]

recent versions of x264 do use GPU hardware via OpenCL, but the performance gain is questionable.

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