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#143 SoXi Amplitude Stats in dB FS

closed
nobody
None
5
2009-07-29
2009-04-03
A440Hz
No

Hi,

A SoXi switch to return the following would be extremely useful:

Peak Amplitude in dB FS of left or right channel in a stereo file and mono files.
Average RMS of same.

Thanks very much for your consideration.

-A440Hz

Discussion

  • robs

    robs - 2009-04-03

    A new `stats' effect has been written for SoX 14.3.0 (due out soon). Here's the manual entry -- will this meet your needs? (Unlike the soxi options, stats is primarily intended as human-readable rather than machine readable)

    stats [-b bits|-x bits|-s scale] [-w window-time]
    Display time domain statistical information about the audio
    channels; audio is passed unmodified through the SoX processing
    chain. For example, for a stereo file:

    Overall Left Right
    DC offset 0.000803 -0.000391 0.000803
    Min level -0.750977 -0.750977 -0.653412
    Max level 0.708801 0.708801 0.653534
    Pk lev dB -2.49 -2.49 -3.69
    RMS lev dB -19.41 -19.13 -19.71
    RMS Pk dB -13.82 -13.82 -14.38
    RMS Tr dB -85.25 -85.25 -82.66
    Crest factor - 6.79 6.32
    Flat factor 0.00 0.00 0.00
    Pk count 2 2 2
    Bit-depth 16/16 16/16 16/16
    Num samples 7.72M
    Length s 174.973
    Scale max 1.000000
    Window s 0.050

    Statistics are calculated and displayed for each audio channel
    and, where applicable, an overall figure is also given.

    DC offset, Min level, and Max level are shown, by default, nor
    malised to 1. If the -b (bits) options is given, then these
    three measurements will be scaled to a signed integer with the
    given number of bits; for example, for 16 bits, the scale would
    be -32768 to +32767. The -x option behaves the same way as -b
    except that the signed integer values are displayed in hexadeci
    mal. The -s option scales the three measurements by a given
    floating-point number.

    Pk lev dB and RMS lev dB are standard peak and RMS level mea
    sured in dBFS. RMS Pk dB and RMS Tr dB are peak and trough val
    ues for RMS level measured over a short window (default 50ms).

    Crest factor is the standard ratio of peak to RMS level (note:
    not in dB).

    Flat factor is a measure of the flatness (i.e. consecutive sam
    ples with the same value) of the signal at its peak levels (i.e.
    either Min level, or Max level). Pk count is the number of
    occasions (not the number of samples) that the signal attained
    either Min level, or Max level.

    The right-hand Bit-depth figure is the standard definition of
    bit-depth i.e. bits less significant than the given number are
    fixed at zero. The left-hand figure is the number of most sig
    nificant bits that are fixed at zero (or one for negative num
    bers) subtracted from the right-hand figure (the number sub
    tracted is directly related to Pk lev dB).

    For multi-channel audio, an overall figure for each of the above
    measurements is given and derived from the channel figures as
    follows: DC offset: maximum magnitude; Max level, Pk lev dB,
    RMS Pk dB, Bit-depth: maximum; Min level, RMS Tr dB: minimum;
    RMS lev dB, Flat factor, Pk count: average; Crest factor: not
    applicable.

    Length s is the duration in seconds of the audio, and Num sam_
    ples is equal to the sample-rate multiplied by Length.
    Scale Max is the scaling applied to the first three measure
    ments; specifically, it is the maximum value that could apply to
    Max level. Window s is the length of the window used for the
    peak and trough RMS measurements.

     
  • A440Hz

    A440Hz - 2009-04-04

    Outstanding!

    I'll capture stderr output and parse whatever I need.

    Thanks you very much for adding this impressive functionality, your efforts are greatly appreciated!!

    -A440Hz

     
  • robs

    robs - 2009-06-28
    • status: open --> pending
     
  • robs

    robs - 2009-06-28

    Released in 14.3.0

     
  • SourceForge Robot

    • status: pending --> closed
     
  • SourceForge Robot

    This Tracker item was closed automatically by the system. It was
    previously set to a Pending status, and the original submitter
    did not respond within 30 days (the time period specified by
    the administrator of this Tracker).

     

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