[FFmpeg-devel] [PATCH] doc/filters: move volume documentation above volumedetect
Stefano Sabatini
stefasab at gmail.com
Sat Dec 8 15:45:49 CET 2012
On date Saturday 2012-12-08 15:21:32 +0100, Clément Bœsch encoded:
> On Sat, Dec 08, 2012 at 12:10:16PM +0100, Stefano Sabatini wrote:
> > ---
> > doc/filters.texi | 80 +++++++++++++++++++++++++++---------------------------
> > 1 file changed, 40 insertions(+), 40 deletions(-)
> >
> > diff --git a/doc/filters.texi b/doc/filters.texi
> > index a2d4a19..57629f9 100644
> > --- a/doc/filters.texi
> > +++ b/doc/filters.texi
> > @@ -829,46 +829,6 @@ out
> > Convert the audio sample format, sample rate and channel layout. This filter is
> > not meant to be used directly.
> >
> > - at section volumedetect
> > -
> > -Detect the volume of the input video.
> > -
> > -The filter has no parameters. The input is not modified. Statistics about
> > -the volume will be printed in the log when the input stream end is reached.
> > -
> > -In particular it will show the mean volume (root mean square), maximum
> > -volume (on a per-sample basis), and the beginning of an histogram of the
> > -registered volume values (from the maximum value to a cumulated 1/1000 of
> > -the samples).
> > -
> > -All volumes are in decibels relative to the maximum PCM value.
> > -
> > -Here is an excerpt of the output:
> > - at example
> > -[Parsed_volumedetect_0 @ 0xa23120] mean_volume: -27 dB
> > -[Parsed_volumedetect_0 @ 0xa23120] max_volume: -4 dB
> > -[Parsed_volumedetect_0 @ 0xa23120] histogram_4db: 6
> > -[Parsed_volumedetect_0 @ 0xa23120] histogram_5db: 62
> > -[Parsed_volumedetect_0 @ 0xa23120] histogram_6db: 286
> > -[Parsed_volumedetect_0 @ 0xa23120] histogram_7db: 1042
> > -[Parsed_volumedetect_0 @ 0xa23120] histogram_8db: 2551
> > -[Parsed_volumedetect_0 @ 0xa23120] histogram_9db: 4609
> > -[Parsed_volumedetect_0 @ 0xa23120] histogram_10db: 8409
> > - at end example
> > -
> > -It means that:
> > - at itemize
> > - at item
> > -The mean square energy is approximately -27 dB, or 10^-2.7.
> > - at item
> > -The largest sample is at -4 dB, or more precisely between -4 dB and -5 dB.
> > - at item
> > -There are 6 samples at -4 dB, 62 at -5 dB, 286 at -6 dB, etc.
> > - at end itemize
> > -
> > -In other words, raising the volume by +4 dB does not cause any clipping,
> > -raising it by +5 dB causes clipping for 6 samples, etc.
> > -
> > @section volume
> >
> > Adjust the input audio volume.
> > @@ -934,6 +894,46 @@ volume=volume=6dB:precision=fixed
> > @end example
> > @end itemize
> >
> > + at section volumedetect
> > +
> > +Detect the volume of the input video.
> > +
> > +The filter has no parameters. The input is not modified. Statistics about
> > +the volume will be printed in the log when the input stream end is reached.
> > +
> > +In particular it will show the mean volume (root mean square), maximum
> > +volume (on a per-sample basis), and the beginning of an histogram of the
> > +registered volume values (from the maximum value to a cumulated 1/1000 of
> > +the samples).
> > +
> > +All volumes are in decibels relative to the maximum PCM value.
> > +
> > +Here is an excerpt of the output:
> > + at example
> > +[Parsed_volumedetect_0 @ 0xa23120] mean_volume: -27 dB
> > +[Parsed_volumedetect_0 @ 0xa23120] max_volume: -4 dB
> > +[Parsed_volumedetect_0 @ 0xa23120] histogram_4db: 6
> > +[Parsed_volumedetect_0 @ 0xa23120] histogram_5db: 62
> > +[Parsed_volumedetect_0 @ 0xa23120] histogram_6db: 286
> > +[Parsed_volumedetect_0 @ 0xa23120] histogram_7db: 1042
> > +[Parsed_volumedetect_0 @ 0xa23120] histogram_8db: 2551
> > +[Parsed_volumedetect_0 @ 0xa23120] histogram_9db: 4609
> > +[Parsed_volumedetect_0 @ 0xa23120] histogram_10db: 8409
> > + at end example
> > +
> > +It means that:
> > + at itemize
> > + at item
> > +The mean square energy is approximately -27 dB, or 10^-2.7.
> > + at item
> > +The largest sample is at -4 dB, or more precisely between -4 dB and -5 dB.
> > + at item
> > +There are 6 samples at -4 dB, 62 at -5 dB, 286 at -6 dB, etc.
> > + at end itemize
> > +
> > +In other words, raising the volume by +4 dB does not cause any clipping,
> > +raising it by +5 dB causes clipping for 6 samples, etc.
> > +
> > @c man end AUDIO FILTERS
> >
> > @chapter Audio Sources
>
> OK
Pushed.
--
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