[FFmpeg-devel] [PATCH] avfilter: add tremolo filter

Lou Logan lou at lrcd.com
Mon Sep 21 20:40:36 CEST 2015


On Mon, 21 Sep 2015 10:16:43 -0500, Kyle Swanson wrote:

> Signed-off-by: Kyle Swanson <k at ylo.ph>
> ---
>  doc/filters.texi         |  19 +++++
>  libavfilter/Makefile     |   1 +
>  libavfilter/af_tremolo.c | 177 +++++++++++++++++++++++++++++++++++++++++++++++
>  libavfilter/allfilters.c |   1 +
>  libavfilter/version.h    |   2 +-
>  5 files changed, 199 insertions(+), 1 deletion(-)
>  create mode 100644 libavfilter/af_tremolo.c
> 
> diff --git a/doc/filters.texi b/doc/filters.texi
> index 88cb3ce..5bbbaf0 100644
> --- a/doc/filters.texi
> +++ b/doc/filters.texi
> @@ -2568,6 +2568,25 @@ slope
>  Determine how steep is the filter's shelf transition.
>  @end table
>  
> + at section tremolo
> +
> +Sinusoidal amplitude modulation.
> +
> +The filter accepts the following options:
> +
> + at table @option
> + at item f
> +Modulation frequency in Hertz. Modulation frequencies in the subharmonic range
> +(20 Hz or lower) will result in a tremolo effect.
> +This filter may also be used as a ring modulator by specifying
> +a modulation frequency higher than 20 Hz.
> +Range is 0.1 - 20000.0. Default value is 5.0 Hz.

This will be rendered as one paragraph in both man and HTML. Not sure if
you want that or not, but it's fine with me as is.

> + at item d
> +Depth of modulation as a percentage. Range is 0.0 - 1.0.
> +Default value is 0.5.
> + at end table

Docs LGTM.


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