avfilter/af_afftdn: add gain_smooth option

This commit is contained in:
Paul B Mahol 2022-04-23 16:06:50 +02:00
parent 16463520d9
commit a64e250680
2 changed files with 17 additions and 0 deletions

View File

@ -1390,6 +1390,12 @@ Stop sample noise capture and measure new noise band profile.
Default value is @code{none}.
@end table
@item gain_smooth, gs
Set gain smooth factor, used to lowpass gains applied to each frequency bin.
Useful to reduce random music noise artefacts.
Higher values reduce smoothing of gains.
Default value is @code{1.0}.
@end table
@subsection Commands

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@ -114,6 +114,7 @@ typedef struct AudioFFTDeNoiseContext {
int output_mode;
int noise_floor_link;
float ratio;
float gain_smooth;
float band_multiplier;
float floor_offset;
@ -207,6 +208,8 @@ static const AVOption afftdn_options[] = {
{ "begin", "start", 0, AV_OPT_TYPE_CONST, {.i64 = SAMPLE_START}, 0, 0, AFR, "sample" },
{ "stop", "stop", 0, AV_OPT_TYPE_CONST, {.i64 = SAMPLE_STOP}, 0, 0, AFR, "sample" },
{ "end", "stop", 0, AV_OPT_TYPE_CONST, {.i64 = SAMPLE_STOP}, 0, 0, AFR, "sample" },
{ "gain_smooth", "set gain smooth factor",OFFSET(gain_smooth), AV_OPT_TYPE_FLOAT, {.dbl = 1.00}, 0.0001, 1, AFR },
{ "gs", "set gain smooth factor",OFFSET(gain_smooth), AV_OPT_TYPE_FLOAT, {.dbl = 1.00}, 0.0001, 1, AFR },
{ NULL }
};
@ -421,6 +424,14 @@ static void process_frame(AVFilterContext *ctx,
}
}
{
const double f = s->gain_smooth;
const double F = 1. - f;
for (int i = 1; i < s->bin_count; i++)
gain[i] = gain[i-1] * F + f * gain[i];
}
for (int i = 0; i < s->bin_count; i++) {
const double new_gain = gain[i];