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audioffmpegrtsprecordingip-camera

how to change the audio bitrate sent by local ip camera?


How can I change the audio bit rate generated by the openrtsp ? I like to have the same bit rate sent by the camera.

./openRTSP "rtsp://user:pass@IP_CAMERA/....."

The bit rate sent by the camera i 64 kb/s but when i try to get informations about the audio output of openrtsp i get 352 kb/s.

  ffmpeg version git-2014-07-16-aa1d096 Copyright (c) 2000-2014 the FFmpeg developers
      built on Jul 16 2014 18:28:34 with gcc 4.6 (Ubuntu/Linaro 4.6.3-1ubuntu5)
      configuration: --extra-cflags=-I/home/zied/junk/include --extra-ldflags=-L/usr/local/lib/ --enable-gpl --enable-libx264
      libavutil      52. 92.100 / 52. 92.100
      libavcodec     55. 69.100 / 55. 69.100
      libavformat    55. 48.100 / 55. 48.100
      libavdevice    55. 13.102 / 55. 13.102
      libavfilter     4. 11.100 /  4. 11.100
      libswscale      2.  6.100 /  2.  6.100
      libswresample   0. 19.100 /  0. 19.100
      libpostproc    52.  3.100 / 52.  3.100
    [mulaw @ 0x9ac0360] Estimating duration from bitrate, this may be inaccurate
    Guessed Channel Layout for  Input Stream #0.0 : mono
    Input #0, mulaw, from 'audio-PCMA-2.ul':
      Duration: 00:00:48.46, bitrate: 352 kb/s
        Stream #0:0: Audio: pcm_mulaw, 44100 Hz, 1 channels, s16, 352 kb/s

Best regards,


Solution

  • openRTSP does not change the bitrate, it just saves incoming samples to file.

    44100 * 8 / 1000 = 352.8 kbps
    

    If you want a lower bitrate, you need to see if your camera supports other audio formats.