Use the Extended MMX instruction set (a subset of SSE) ([mmxext] or [sse] in cpuinfo)
Name Category Description
ffmpeg media-video Complete solution to record/convert/stream audio and video. Includes libavcodec
ffmpeg-chromium media-video FFmpeg built specifically for codec support in Chromium-based browsers
mplayer media-video Media Player for Linux
pixman x11-libs Low-level pixel manipulation routines

Thank you!