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  1. Member
    Join Date: Dec 2010
    Location: USA
    Search Comp PM
    Hello,
    Does anyone know what the output items are in ffplay?
    In particular I am seeing what may be a audio quality factor but the units are KB.
    There is an "aq=" value that seems to be higher as quality goes up.
    I don't understand what it may be calculating and wonder if it will help me to choose my encoding params.
    Thank You
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  2. Member
    Join Date: Mar 2011
    Location: Nova Scotia, Canada
    Search Comp PM
    I think aq means adaptive quantization but that doesn't have anything to do with audio.
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  3. Member
    Join Date: Dec 2010
    Location: USA
    Search Comp PM
    Rob,
    Thanks for the suggestion. There are two params "aq=" and "vq=" and when playing a video with sound I see both vary and when just playing an mp3 I only see the aq vary. This is hard. I have been studying the source code for several hours but have not found the code that computes these parameters. I am rusty on the doxygen tool output and git in general so I get lost often. I did find a generic list of what the 'stats' that are output:
    " Print several playback statistics, in particular show the stream duration, the codec parameters,
    the current position in the stream and the audio/video synchronisation drift"
    If I can put the time on the code maybe I'll figure this out. If so I'll post what I find. I don't know why I got locked onto this problem. But I am seeing aq values in the 80-95 range for some test audio that is 24bit 96kHz flac and only 5-8 for my 16bit 44kHz 320 kbps mp3.
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