avfilter/af_aiir: fix biquads normalization

This commit is contained in:
Paul B Mahol 2019-11-22 20:24:29 +01:00
parent eecc45cea5
commit f2a01b4c8b
1 changed files with 12 additions and 7 deletions

View File

@ -594,16 +594,21 @@ static int decompose_zp2biquads(AVFilterContext *ctx, int channels)
iir->ab[1][2 * nearest_zero.a] = iir->ab[1][2 * nearest_zero.a + 1] = NAN;
iir->ab[1][2 * nearest_zero.b] = iir->ab[1][2 * nearest_zero.b + 1] = NAN;
iir->biquads[current_biquad].a[0] = a[4];
iir->biquads[current_biquad].a[1] = a[2];
iir->biquads[current_biquad].a[2] = a[0];
iir->biquads[current_biquad].b[0] = b[4];
iir->biquads[current_biquad].b[1] = b[2];
iir->biquads[current_biquad].b[2] = b[0];
iir->biquads[current_biquad].a[0] = 1.;
iir->biquads[current_biquad].a[1] = a[2] / a[4];
iir->biquads[current_biquad].a[2] = a[0] / a[4];
iir->biquads[current_biquad].b[0] = b[4] / a[4];
iir->biquads[current_biquad].b[1] = b[2] / a[4];
iir->biquads[current_biquad].b[2] = b[0] / a[4];
factor = (iir->biquads[current_biquad].a[0] +
iir->biquads[current_biquad].a[1] +
iir->biquads[current_biquad].a[2]) / 4;
iir->biquads[current_biquad].a[2]) /
(iir->biquads[current_biquad].b[0] +
iir->biquads[current_biquad].b[1] +
iir->biquads[current_biquad].b[2]);
av_log(ctx, AV_LOG_VERBOSE, "factor=%f\n", factor);
iir->biquads[current_biquad].b[0] *= factor;
iir->biquads[current_biquad].b[1] *= factor;