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We are using Amazon EC2 m1.xlarge instance for video re-encoding and it looks like the actual encoding process takes a very long time. For an average 250mb video file it takes about an hour to encode.

Intance: m1.xlarge (Xeon E5645 x 15gb ram)
Windows Server 2008 R2 64-bit
AviSynth version 2.5 (32bit) + ffms2 plugin (FFmpegSource 1.21)
FFmpeg SVN-r13712
libavutil   3213056
libavcodec  3356930
libavformat 3411456
libavdevice 3407872
Number of parallel jobs is 3
Average CPU utilization ~96%

Update#1 Source video: mp4/h.264

Parameters for ffmpeg:

--enable-memalign-hack --enable-avisynth --enable-libxvid --enable-libx264 +
--enable-libgsm --enable-libfaac --enable-libfaad --enable-liba52 +
--enable-libmp3lame --enable-libvorbis --enable-libtheora --enable-pthreads +
--enable-swscale --enable-gpl

Video files encoded to mp4/h.264 with the following extra command line options:

-threads 0 -coder 0 -bf 0 -refs 1 -level 30 -maxrate 10000000 -bufsize 10000000
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And? Video encoding takes a while. –  ceejayoz Nov 26 '12 at 22:06
Please give details of input video codec and encoding profile –  Alastair McCormack Nov 26 '12 at 22:08
Hm, not sure why the question was downgraded... –  Timka Nov 26 '12 at 22:25
Video encoding is very slow. –  Tom O'Connor Nov 26 '12 at 22:28
I disagree, this sounds unusually slow. Even on small instances I can achieve real time x264 encoding from MP2 but is heavily dependent on the input and the output. Please give more details! –  Alastair McCormack Nov 26 '12 at 22:37
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