title: Encoder (codec none) not found for output stream #0:1
body: <p>Hi i built ffmpeg executable on Redhat5. I want to mix two Audio using the command multiple
  "ffmpeg -i INPUT1 -i INPUT2 -i INPUT3 -filter_complex amix=inputs=3:duration=first:dropout_transition=3 OUTPUT.mp3". </p>
  
  <p>I enabled libflamemp3 library without any error. </p>
  
  <pre><code>[root@localhost ~]# ffmpeg -i /root/media/Katlalli.mp3 -i /root/media/Katlalli.mp3 -filter_complex amix=inputs=2:duration=first:dropout_transition=2 /root/media/OUTPutnew123.mp3
  ffmpeg version 2.1 Copyright (c) 2000-2013 the FFmpeg developers
    built on Nov 14 2013 03:17:10 with gcc 4.1.2 (GCC) 20080704 (Red Hat 4.1.2-46)
    configuration: --enable-libmp3lame
    libavutil      52. 48.100 / 52. 48.100
    libavcodec     55. 39.100 / 55. 39.100
    libavformat    55. 19.104 / 55. 19.104
    libavdevice    55.  5.100 / 55.  5.100
    libavfilter     3. 90.100 /  3. 90.100
    libswscale      2.  5.101 /  2.  5.101
    libswresample   0. 17.104 /  0. 17.104
  [mp3 @ 0x193ef240] Estimating duration from bitrate, this may be inaccurate
  Input #0, mp3, from '/root/media/Katlalli.mp3':
    Metadata:
      artist          : Yograj Bhat
      title           : Katlalli Karadige
      track           : 3
      album           : Paramathma
      album_artist    : Puneet Rajkumar
      genre           : Kannada
      composer        : V.Harikrishna
      date            : 2011
    Duration: 00:04:41.46, start: 0.000000, bitrate: 191 kb/s
      Stream #0:0: Audio: mp3, 44100 Hz, stereo, s16p, 192 kb/s
      Stream #0:1: Video: mjpeg, yuvj420p(pc), 200x200 [SAR 96:96 DAR 1:1], 90k tbr, 90k tbn, 90k tbc
      Metadata:
        title           : thumbnail
        comment         : Cover (front)
  [mp3 @ 0x194090a0] Estimating duration from bitrate, this may be inaccurate
  Input #1, mp3, from '/root/media/Katlalli.mp3':
    Metadata:
      artist          : Yograj Bhat
      title           : Katlalli Karadige
      track           : 3
      album           : Paramathma
      album_artist    : Puneet Rajkumar
      genre           : Kannada
      composer        : V.Harikrishna
      date            : 2011
    Duration: 00:04:41.46, start: 0.000000, bitrate: 191 kb/s
      Stream #1:0: Audio: mp3, 44100 Hz, stereo, s16p, 192 kb/s
      Stream #1:1: Video: mjpeg, yuvj420p(pc), 200x200 [SAR 96:96 DAR 1:1], 90k tbr, 90k tbn, 90k tbc
      Metadata:
        title           : thumbnail
        comment         : Cover (front)
  File '/root/media/OUTPutnew123.mp3' already exists. Overwrite ? [y/N] y
  Output #0, mp3, to '/root/media/OUTPutnew123.mp3':
    Metadata:
      artist          : Yograj Bhat
      title           : Katlalli Karadige
      track           : 3
      album           : Paramathma
      album_artist    : Puneet Rajkumar
      genre           : Kannada
      composer        : V.Harikrishna
      date            : 2011
      Stream #0:0: Audio: mp3, 44100 Hz, stereo, fltp (default)
      Stream #0:1: Video: none, q=2-31, 128 kb/s, 90k tbn
      Metadata:
        title           : thumbnail
        comment         : Cover (front)
  Stream mapping:
    Stream #0:0 (mp3) -&gt; amix:input0
    Stream #1:0 (mp3) -&gt; amix:input1
    amix -&gt; Stream #0:0 (libmp3lame)
    Stream #0:1 -&gt; #0:1 (mjpeg -&gt; ?)
  Encoder (codec none) not found for output stream #0:1
  </code></pre>
  
  <p>But when i try to combine two mp3 audio, 
  "ffmpeg -i INPUT1 -i INPUT2 -i INPUT3 -filter_complex amix=inputs=3:duration=first:dropout_transition=3 OUTPUT.mp3".</p>
  
  <p>I am getting error like </p>
  
  <p>"Encoder (codec none) not found for output stream #0:1"</p>
  
  <p>so please help me how to link or install "libmp3flame" on Redhat5.</p>