[FFmpeg-devel] [PATCH] avfilter/af_loudnorm: add dual_mono option

[Kyle Swanson]

On Tue, Jun 7, 2016 at 11:55 AM, Kyle Swanson <k at ylo.ph> wrote:
> Signed-off-by: Kyle Swanson <k at ylo.ph>
> ---
>  doc/filters.texi          | 7 +++++++
>  libavfilter/af_loudnorm.c | 7 +++++++
>  2 files changed, 14 insertions(+)
>
> diff --git a/doc/filters.texi b/doc/filters.texi
> index d9330e3..439baf9 100644
> --- a/doc/filters.texi
> +++ b/doc/filters.texi
> @@ -2765,6 +2765,13 @@ measured_I, measured_LRA, measured_TP, and measured_thresh must also
>  to be specified in order to use this mode.
>  Options are true or false. Default is true.
>
> + at item dual_mono
> +Treat mono input files as "dual-mono". If a mono file is intended for playback
> +on a stereo system, its EBU R128 measurement will be perceptually incorrect.
> +If set to @code{true}, this option will compensate for this effect.
> +Multi-channel input files are not affected by this option.
> +Options are true or false. Default is false.
> +
>  @item print_format
>  Set print format for stats. Options are summary, json, or none.
>  Default value is none.
> diff --git a/libavfilter/af_loudnorm.c b/libavfilter/af_loudnorm.c
> index 9d27c16..604697e 100644
> --- a/libavfilter/af_loudnorm.c
> +++ b/libavfilter/af_loudnorm.c
> @@ -60,6 +60,7 @@ typedef struct LoudNormContext {
>      double measured_thresh;
>      double offset;
>      int linear;
> +    int dual_mono;
>      enum PrintFormat print_format;
>
>      double *buf;
> @@ -113,6 +114,7 @@ static const AVOption loudnorm_options[] = {
>      { "measured_thresh",  "measured threshold of input file",  OFFSET(measured_thresh),  AV_OPT_TYPE_DOUBLE,  {.dbl = -70.},   -99.,        0.,  FLAGS },
>      { "offset",           "set offset gain",                   OFFSET(offset),           AV_OPT_TYPE_DOUBLE,  {.dbl =  0.},    -99.,       99.,  FLAGS },
>      { "linear",           "normalize linearly if possible",    OFFSET(linear),           AV_OPT_TYPE_BOOL,    {.i64 =  1},        0,         1,  FLAGS },
> +    { "dual_mono",        "treat mono input as dual-mono",     OFFSET(dual_mono),        AV_OPT_TYPE_BOOL,    {.i64 =  0},        0,         1,  FLAGS },
>      { "print_format",     "set print format for stats",        OFFSET(print_format),     AV_OPT_TYPE_INT,     {.i64 =  NONE},  NONE,  PF_NB -1,  FLAGS, "print_format" },
>      {     "none",         0,                                   0,                        AV_OPT_TYPE_CONST,   {.i64 =  NONE},     0,         0,  FLAGS, "print_format" },
>      {     "json",         0,                                   0,                        AV_OPT_TYPE_CONST,   {.i64 =  JSON},     0,         0,  FLAGS, "print_format" },
> @@ -731,6 +733,11 @@ static int config_input(AVFilterLink *inlink)
>      if (!s->r128_out)
>          return AVERROR(ENOMEM);
>
> +    if (inlink->channels == 1 && s->dual_mono) {
> +        ebur128_set_channel(s->r128_in,  0, EBUR128_DUAL_MONO);
> +        ebur128_set_channel(s->r128_out, 0, EBUR128_DUAL_MONO);
> +    }
> +
>      s->buf_size = frame_size(inlink->sample_rate, 3000) * inlink->channels;
>      s->buf = av_malloc_array(s->buf_size, sizeof(*s->buf));
>      if (!s->buf)
> --
> 2.5.4 (Apple Git-61)
>

Pushed. Thanks.