How to use ffmpeg to encode video in H.264?
<p>I have installed ffmpeg 3.0 from <a href="https://github.com/FFmpeg/FFmpeg" rel="nofollow">https://github.com/FFmpeg/FFmpeg</a>, I am trying to convert a video coded with mepeg4 part 2 to H264, but I got <code>Unknown encoder 'libx264'</code>
 error</p>

<p>Here is my comannd: (I tried h264, x264, libx264, none of them worked)</p>

<pre><code>ffmpeg -i Fashion.divx -acodec aac -vcodec libx264  out.mp4
</code></pre>

<p>I checked the list of supported codec</p>

<pre><code>Codecs:
 D..... = Decoding supported
 .E.... = Encoding supported
 ..V... = Video codec
 ..A... = Audio codec
 ..S... = Subtitle codec
 ...I.. = Intra frame-only codec
 ....L. = Lossy compression
 .....S = Lossless compression
 -------
 D.VI.. 012v                 Uncompressed 4:2:2 10-bit
</code></pre>

<p>Here is h264:</p>

<pre><code> D.V.LS h264                 H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10 (decoders: h264 h264_vdpau)
</code></pre>

<p>I am using ffmpeg 3.0, from that list, it seems that encoding with h264 is not supported, only decoding h264 is supported, right?</p>

<p>I tried to enable h.264 with this guide 
<a href="https://trac.ffmpeg.org/wiki/How%20to%20quickly%20compile%20FFmpeg%20with%20libx264%20%28x264,%20H.264%29" rel="nofollow">How to quickly compile FFmpeg with libx264 (x264, H.264)</a></p>

<pre><code>./configure --enable-gpl --enable-libx264
</code></pre>

<p>bu I get 
 ./configure --enable-gpl --enable-libx264 </p>

<pre><code>ERROR: libx264 not found

If you think configure made a mistake, make sure you are using the latest
version from Git.  If the latest version fails, report the problem to the
ffmpeg-user@ffmpeg.org mailing list or IRC #ffmpeg on irc.freenode.net.
Include the log file "config.log" produced by configure as this will help
solve the problem.
</code></pre>

<p>what should I do to make encode video in h.264 work?</p>