title: ffmpeg output separate channel from an input with multiple channels
body: <p>i run this command to be able to stream a udp live stream to a http live stream that is playable using a mobile application that am building.
  its just a stream with audio streams only.</p>
  
  <p>ffmpeg -i udp://@localhost:1111 -map 0:a  <a href="http://localhost:8090/feed1.ffm" rel="nofollow noreferrer">http://localhost:8090/feed1.ffm</a></p>
  
  <pre><code>Input #0, mpegts, from 'udp://@localhost:1111':
    Duration: N/A, start: 54616.264622, bitrate: 768 kb/s
    Program 1
      Metadata:
    service_name    : Service 1
    service_provider: TLK
      Stream #0:0[0x101]: Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, stereo, s16p, 96 kb/s
    Program 2
  Metadata:
    service_name    : Service 2
    service_provider: TLK
  Stream #0:1[0x111]: Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, stereo, s16p, 96 kb/s
   Program 3
  Metadata:
    service_name    : Service 3
    service_provider: TLK
  Stream #0:2[0x121]: Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, stereo, s16p, 96 kb/s
   Program 4
  Metadata:
    service_name    : Service 4
    service_provider: TLK
  Stream #0:3[0x131]: Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, stereo, s16p, 96 kb/s
    Program 5
  Metadata:
    service_name    : Service 5
    service_provider: TLK
  Stream #0:4[0x141]: Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, stereo, s16p, 96 kb/s
    Program 6
  Metadata:
    service_name    : Service 6
    service_provider: TLK
  Stream #0:5[0x151]: Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, stereo, s16p, 96 kb/s
    Program 7
  Metadata:
    service_name    : Service 7
    service_provider: TLK
  Stream #0:6[0x161]: Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, stereo, s16p, 96 kb/s
   Program 8
  Metadata:
    service_name    : Service 1
    service_provider: TLK
  Stream #0:7[0x171]: Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, stereo, s16p, 96 kb/s
  </code></pre>
  
  <p>i get this output</p>
  
  <pre><code>Stream mapping:
    Stream #0:0 -&gt; #0:0 (mp2 (native) -&gt; mp2 (native))
    Stream #0:0 -&gt; #0:1 (mp2 (native) -&gt; mp2 (native))
  Press [q] to stop, [?] for help
  size=     100kB time=00:00:07.19 bitrate= 113.8kbits/s speed=3.01x
  video:0kB audio:84kB subtitle:0kB other streams:0kB global headers:0kB  muxing overhead: 18.358242%
  </code></pre>
  
  <p>i really want a way i can be able to map every input stream to have an output stream that can be accessed separately from the other like maybe if i need the first stream maybe i will just </p>
  
  <pre><code>ffplay http://localhost:8090/feed1.ffm 
  </code></pre>
  
  <p>and if i need the 7th stream i will just </p>
  
  <pre><code>ffplay http://localhost:8090/feed7.ffm
  </code></pre>
  
  <p>Please can someone help me crack this issue. FFmpeg dont have complex examples for my current situation.</p>
  
  <p>this is my header information</p>
  
  <pre><code>ubuntu@ip-localhost:~$ \ 
  ffmpeg -i udp://@localhost:4000 \
    -map 0:a:0     http://localhost:8090/feed1.ffm 
    -map 0:a:1 http://localhost:8090/feed2.ffm 
    -map 0:a:2 http://localhost:8090/feed3.ffm 
    -map 0:a:3 http://localhost:8090/feed4.ffm 
    -map 0:a:4 http://localhost:8090/feed5.ffm 
    -map 0:a:5 http://localhost:8090/feed6.ffm 
    -map 0:a:6 http://localhost:8090/feed7.ffm 
    -map 0:a:7 http://localhost:8090/feed8.ffm
  </code></pre>
  
  <p>ffmpeg version 3.2.4-1~16.04.york0 Copyright (c) 2000-2017 the FFmpeg    developers built with gcc 5.4.1 (Ubuntu 5.4.1-5ubuntu2~16.04.york1) 20170210
    configuration: --prefix=/usr --extra-version='1~16.04.york0' -- toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --enable-gpl --disable-stripping --enable-avresample --enable-avisynth --enable-gnutls --enable-ladspa --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libebur128 --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libmp3lame --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librubberband --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-omx --enable-openal --enable-opengl --enable-sdl2 --enable-libdc1394 --enable-libiec61883 --enable-chromaprint --enable-frei0r --enable-libopencv --enable-libx264 --enable-shared
    libavutil      55. 34.101 / 55. 34.101
    libavcodec     57. 64.101 / 57. 64.101
    libavformat    57. 56.101 / 57. 56.101
    libavdevice    57.  1.100 / 57.  1.100
    libavfilter     6. 65.100 /  6. 65.100
    libavresample   3.  1.  0 /  3.  1.  0
    libswscale      4.  2.100 /  4.  2.100
    libswresample   2.  3.100 /  2.  3.100
    libpostproc    54.  1.100 / 54.  1.100</p>
  
  <pre><code>Input #0, mpegts, from 'udp://@localhost:1111':
    Duration: N/A, start: 60047.944622, bitrate: 768 kb/s
    Program 1
      Metadata:
    service_name    : Service 1
    service_provider: TKL
  Stream #0:0[0x101]: Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, stereo, s16p, 96 kb/s
   Program 2
  Metadata:
    service_name    : Service 2
    service_provider: TKL
  Stream #0:1[0x111]: Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, stereo, s16p, 96 kb/s
   Program 3
  Metadata:
    service_name    : Service 3
    service_provider: TKL
  Stream #0:2[0x121]: Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, stereo, s16p, 96 kb/s
  Program 4
  Metadata:
    service_name    : Service 4
    service_provider: TKL
  Stream #0:3[0x131]: Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, stereo, s16p, 96 kb/s
  Program 5
  Metadata:
    service_name    : Service 5
    service_provider: TKL
  Stream #0:4[0x141]: Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, stereo, s16p, 96 kb/s
  Program 6
  Metadata:
    service_name    : Service 6
    service_provider: TKL
  Stream #0:5[0x151]: Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, stereo, s16p, 96 kb/s
  Program 7
  Metadata:
    service_name    : Service 7
    service_provider: TKL
  Stream #0:6[0x161]: Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, stereo, s16p, 96 kb/s
  Program 8
  Metadata:
    service_name    : Service 8
    service_provider: TKL
  Stream #0:7[0x171]: Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, stereo, s16p, 96 kb/s
  Output #0, ffm, to 'http://localhost:8090/feed1.ffm':
  Metadata:
  creation_time   : now
  encoder         : Lavf57.56.101
  Stream #0:0: Audio: mp2, 44100 Hz, mono, s16, 32 kb/s
  Metadata:
    encoder         : Lavc57.64.101 mp2
  Stream #0:1: Audio: mp2, 44100 Hz, stereo, s16, 64 kb/s
  Metadata:
    encoder         : Lavc57.64.101 mp2
  Output #1, ffm, to 'http://localhost:8090/feed2.ffm':
  Metadata:
  creation_time   : now
  encoder         : Lavf57.56.101
  Stream #1:0: Audio: mp2, 44100 Hz, stereo, s16, 64 kb/s
  Metadata:
    encoder         : Lavc57.64.101 mp2
  Output #2, ffm, to 'http://localhost:8090/feed3.ffm':
  Metadata:
  creation_time   : now
  encoder         : Lavf57.56.101
  Stream #2:0: Audio: mp2, 44100 Hz, stereo, s16, 64 kb/s
  Metadata:
    encoder         : Lavc57.64.101 mp2
  Output #3, ffm, to 'http://localhost:8090/feed4.ffm':
  Metadata:
  creation_time   : now
  encoder         : Lavf57.56.101
  Stream #3:0: Audio: mp2, 44100 Hz, stereo, s16, 64 kb/s
  Metadata:
    encoder         : Lavc57.64.101 mp2
  Output #4, ffm, to 'http://localhost:8090/feed5.ffm':
  Metadata:
  creation_time   : now
  encoder         : Lavf57.56.101
  Stream #4:0: Audio: mp2, 44100 Hz, stereo, s16, 64 kb/s
  Metadata:
    encoder         : Lavc57.64.101 mp2
  Output #5, ffm, to 'http://localhost:8090/feed6.ffm':
  Metadata:
  creation_time   : now
  encoder         : Lavf57.56.101
  Stream #5:0: Audio: mp2, 44100 Hz, stereo, s16, 64 kb/s
  Metadata:
    encoder         : Lavc57.64.101 mp2
  Output #6, ffm, to 'http://localhost:8090/feed7.ffm':
  Metadata:
  creation_time   : now
  encoder         : Lavf57.56.101
  Stream #6:0: Audio: mp2, 44100 Hz, stereo, s16, 64 kb/s
  Metadata:
    encoder         : Lavc57.64.101 mp2
  Output #7, ffm, to 'http://localhost:8090/feed8.ffm':
  Metadata:
  creation_time   : now
  encoder         : Lavf57.56.101
  Stream #7:0: Audio: mp2, 44100 Hz, stereo, s16, 64 kb/s
  Metadata:
    encoder         : Lavc57.64.101 mp2
  Stream mapping:
  Stream #0:0 -&gt; #0:0 (mp2 (native) -&gt; mp2 (native))
  Stream #0:0 -&gt; #0:1 (mp2 (native) -&gt; mp2 (native))
  Stream #0:0 -&gt; #1:0 (mp2 (native) -&gt; mp2 (native))
  Stream #0:0 -&gt; #2:0 (mp2 (native) -&gt; mp2 (native))
  Stream #0:0 -&gt; #3:0 (mp2 (native) -&gt; mp2 (native))
  Stream #0:0 -&gt; #4:0 (mp2 (native) -&gt; mp2 (native))
  Stream #0:0 -&gt; #5:0 (mp2 (native) -&gt; mp2 (native))
  Stream #0:0 -&gt; #6:0 (mp2 (native) -&gt; mp2 (native))
  Stream #0:0 -&gt; #7:0 (mp2 (native) -&gt; mp2 (native))
  Press [q] to stop, [?] for help
  </code></pre>
  
  <p>thats my full console.</p>