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I'm testing ClipBucket on a Windows XP system, and ClipBucket (open source video share) uses FFmpeg to convert videos. The final command it executes is (i changed it a little to make it compatible with the current FFmpeg):

D:\ffmpeg-snapshot-git\ffmpeg\ffmpeg.exe -i C:
\wamp\www\cb/files/conversion_queue/1352973741c353c.mp4 -f flv -vcodec libx2
64 -pre normal -r 25 -s 426x240 -aspect 1.775 -vf "pad=10:20:30:40:yellow"  -ac
odec libfaac -ab 128000 -ar 22050 C:\wamp\www\cb/files/videos/13540939451e18
4.flv 2> C:\wamp\www\cb/files/temp/13540939461c124.tmp 2>&1

And this is the response I get:

ffmpeg version 1.0.git Copyright (c) 2000-2012 the FFmpeg developers
built on Nov 19 2012 16:42:42 with gcc 4.6.2 (GCC)
libavutil      52.  8.100 / 52.  8.100
libavcodec     54. 73.100 / 54. 73.100
libavformat    54. 37.100 / 54. 37.100
libavdevice    54.  3.100 / 54.  3.100
libavfilter     3. 23.101 /  3. 23.101
libswscale      2.  1.102 /  2.  1.102
libswresample   0. 16.100 /  0. 16.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'C:\wamp\www\cb/files/conversion_que
major_brand     : isom
minor_version   : 512
compatible_brands: isomiso2avc1mp41
encoder         : Lavf53.21.0
Duration: 00:00:51.67, start: 0.000000, bitrate: 344 kb/s
Stream #0:0(und): Video: h264 (Main) (avc1 / 0x31637661), yuv420p, 426x240 [
SAR 1:1 DAR 71:40], 308 kb/s, 15 fps, 15 tbr, 15 tbn, 30 tbc
handler_name    : VideoHandler
Stream #0:1(und): Audio: aac (mp4a / 0x6134706D), 44100 Hz, stereo, s16, 31
handler_name    : SoundHandler
Unknown encoder 'libx264'

How can I get this libx264 working in Windows?

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migrated from Nov 29 '12 at 13:57

This question came from our site for professional and enthusiast programmers.

up vote 4 down vote accepted

Your ffmpeg has not been configured with --enable-gpl --enable-libx264 which are required for ffmpeg to support libx264. Either re-compile ffmpeg, or download it from Zeranoe FFmpeg Windows builds which includes libx264 support.

Note that Zeranoe's ffmpeg does not contain libfaac support due to that encoder requiring --enable-nonfree which would result in a non-redistributable build. Zeranoe's ffmpeg does support other AAC encoders including the native ffmpeg AAC encoder, aac (which requires usage of the -strict experimental option), and libvo_aacenc which unfortunately isn't any better than the native encoder. See FFmpeg AACの音質評価 for a comparison (in Japanese).

Other audio options include re-compiling ffmpeg to support fdk-aac, using a different audio format, or piping to an external audio encoder and muxing the output with ffmpeg.

Also see:

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believe it or not i thought about super user, but the conclusion was "i may need some compiling" so i preferred stack overflow. – shampoo Nov 29 '12 at 6:57
for compiling with libfaac how should i configure it? --enable-nonfree needs --enable-libfaac too? i know, i can test these configs but windows takes about ten minutes to build ffmpeg.exe using mingw. testing it one config by one config including research for config would probably take one week. – shampoo Nov 29 '12 at 7:05
@shampoo I don't consider compiling to be programming, but it's no big deal. FFmpeg's configure should tell you if something is missing before you run make, but to answer your question, yes, --enable-libfaac also requires --enable-nonfree. However, I recommend fdk-aac over libfaac: it should provide better quality at similar bitrates. – LordNeckbeard Nov 29 '12 at 7:35

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