diff options
Diffstat (limited to 'gst/equalizer/gstiirequalizer.c')
| -rw-r--r-- | gst/equalizer/gstiirequalizer.c | 27 |
1 files changed, 21 insertions, 6 deletions
diff --git a/gst/equalizer/gstiirequalizer.c b/gst/equalizer/gstiirequalizer.c index 25ee6972..cd955e28 100644 --- a/gst/equalizer/gstiirequalizer.c +++ b/gst/equalizer/gstiirequalizer.c @@ -232,7 +232,7 @@ gst_iir_equalizer_band_class_init (GstIirEqualizerBandClass * klass) g_object_class_install_property (gobject_class, ARG_BANDWIDTH, g_param_spec_double ("bandwidth", "bandwidth", "difference between bandedges in Hz", - 1.0, 100000.0, 1.0, G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE)); + 0.0, 100000.0, 1.0, G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE)); } static void @@ -390,12 +390,26 @@ setup_filter (GstIirEqualizer * equ, GstIirEqualizerBand * band) else omega = 2.0 * M_PI * (band->freq / GST_AUDIO_FILTER (equ)->format.rate); - if (band->width / GST_AUDIO_FILTER (equ)->format.rate > 0.5) - bw = M_PI; - else if (band->width <= 1.0) - bw = 2.0 * M_PI * (1.0 / GST_AUDIO_FILTER (equ)->format.rate); - else + if (band->width / GST_AUDIO_FILTER (equ)->format.rate >= 0.5) { + /* If bandwidth == 0.5 the calculation below fails as tan(M_PI/2) + * is undefined. So set the bandwidth to a slightly smaller value. + */ + bw = M_PI - 0.00000001; + } else if (band->width <= 0.0) { + /* If bandwidth == 0 this band won't change anything so set + * the coefficients accordingly. The coefficient calculation + * below would create coefficients that for some reason amplify + * the band. + */ + band->a0 = 1.0; + band->a1 = 0.0; + band->a2 = 0.0; + band->b1 = 0.0; + band->b2 = 0.0; + goto out; + } else { bw = 2.0 * M_PI * (band->width / GST_AUDIO_FILTER (equ)->format.rate); + } edge_gain = sqrt (gain); gamma = tan (bw / 2.0); @@ -409,6 +423,7 @@ setup_filter (GstIirEqualizer * equ, GstIirEqualizerBand * band) band->b1 = (2.0 * cos (omega)) / (1.0 + beta); band->b2 = -(1.0 - beta) / (1.0 + beta); + out: GST_INFO ("gain = %7.5g, , bandwidth= %7.5g, frequency = %7.5g, a0 = %7.5g, a1 = %7.5g, a2=%7.5g b1 = %7.5g, b2 = %7.5g", band->gain, band->width, band->freq, band->a0, band->a1, band->a2, |