[FFmpeg-cvslog] avfilter/af_adynamicequalizer: set target filter type

[Paul B Mahol]

ffmpeg | branch: master | Paul B Mahol <onemda at gmail.com> | Thu Apr 28 21:57:49 2022 +0200| [c27123606a4413a9ee39ffe4271b1c28013970ef] | committer: Paul B Mahol

avfilter/af_adynamicequalizer: set target filter type

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=c27123606a4413a9ee39ffe4271b1c28013970ef
---

 doc/filters.texi                   | 10 ++++++++++
 libavfilter/af_adynamicequalizer.c | 37 +++++++++++++++++++++++++++++++++++--
 2 files changed, 45 insertions(+), 2 deletions(-)

diff --git a/doc/filters.texi b/doc/filters.texi
index 52c40833eb..66f1c543be 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -913,6 +913,16 @@ Cut frequencies above detection threshold.
 Boost frequencies bellow detection threshold.
 @end table
 Default mode is @samp{cut}.
+
+ at item tftype
+Set the type of target filter, can be one of the following:
+
+ at table @samp
+ at item bell
+ at item lowshelf
+ at item highshelf
+ at end table
+Default type is @samp{bell}.
 @end table
 
 @subsection Commands
diff --git a/libavfilter/af_adynamicequalizer.c b/libavfilter/af_adynamicequalizer.c
index b51491391d..b6d438f698 100644
--- a/libavfilter/af_adynamicequalizer.c
+++ b/libavfilter/af_adynamicequalizer.c
@@ -42,6 +42,7 @@ typedef struct AudioDynamicEqualizerContext {
     double attack_coef;
     double release_coef;
     int mode;
+    int type;
 
     AVFrame *state;
 } AudioDynamicEqualizerContext;
@@ -160,6 +161,7 @@ static int filter_channels(AVFilterContext *ctx, void *arg, int jobnr, int nb_jo
     const int start = (in->ch_layout.nb_channels * jobnr) / nb_jobs;
     const int end = (in->ch_layout.nb_channels * (jobnr+1)) / nb_jobs;
     const int mode = s->mode;
+    const int type = s->type;
     const double knee = s->knee;
     const double slew = s->slew;
     const double aattack = exp(-1000. / ((s->attack + 2.0 * (slew - 1.)) * sample_rate));
@@ -186,6 +188,7 @@ static int filter_channels(AVFilterContext *ctx, void *arg, int jobnr, int nb_jo
         for (int n = 0; n < out->nb_samples; n++) {
             double detect, gain, v, listen;
             double fa[3], fm[3];
+            double k, g;
 
             detect = listen = get_svf(src[n], dm, da, state);
             detect = fabs(detect);
@@ -194,8 +197,9 @@ static int filter_channels(AVFilterContext *ctx, void *arg, int jobnr, int nb_jo
                             aattack, iratio, knee, range, threshold, slew,
                             &state[4], attack, release, nc);
 
-            {
-                double k = 1. / (tqfactor * gain);
+            switch (type) {
+            case 0:
+                k = 1. / (tqfactor * gain);
 
                 fa[0] = 1. / (1. + fg * (fg + k));
                 fa[1] = fg * fa[0];
@@ -204,6 +208,31 @@ static int filter_channels(AVFilterContext *ctx, void *arg, int jobnr, int nb_jo
                 fm[0] = 1.;
                 fm[1] = k * (gain * gain - 1.);
                 fm[2] = 0.;
+                break;
+            case 1:
+                k = 1. / tqfactor;
+                g = fg / sqrt(gain);
+
+                fa[0] = 1. / (1. + g * (g + k));
+                fa[1] = g * fa[0];
+                fa[2] = g * fa[1];
+
+                fm[0] = 1.;
+                fm[1] = k * (gain - 1.);
+                fm[2] = gain * gain - 1.;
+                break;
+            case 2:
+                k = 1. / tqfactor;
+                g = fg / sqrt(gain);
+
+                fa[0] = 1. / (1. + g * (g + k));
+                fa[1] = g * fa[0];
+                fa[2] = g * fa[1];
+
+                fm[0] = gain * gain;
+                fm[1] = k * (1. - gain) * gain;
+                fm[2] = 1. - gain * gain;
+                break;
             }
 
             v = get_svf(src[n], fm, fa, &state[2]);
@@ -279,6 +308,10 @@ static const AVOption adynamicequalizer_options[] = {
     {   "listen",   0,                         0,                  AV_OPT_TYPE_CONST,  {.i64=-1},       0, 0,       FLAGS, "mode" },
     {   "cut",      0,                         0,                  AV_OPT_TYPE_CONST,  {.i64=0},        0, 0,       FLAGS, "mode" },
     {   "boost",    0,                         0,                  AV_OPT_TYPE_CONST,  {.i64=1},        0, 0,       FLAGS, "mode" },
+    { "tftype",     "set target filter type",  OFFSET(type),       AV_OPT_TYPE_INT,    {.i64=0},        0, 2,       FLAGS, "type" },
+    {   "bell",     0,                         0,                  AV_OPT_TYPE_CONST,  {.i64=0},        0, 0,       FLAGS, "type" },
+    {   "lowshelf", 0,                         0,                  AV_OPT_TYPE_CONST,  {.i64=1},        0, 0,       FLAGS, "type" },
+    {   "highshelf",0,                         0,                  AV_OPT_TYPE_CONST,  {.i64=2},        0, 0,       FLAGS, "type" },
     { NULL }
 };