[SCM] calf/master: + Compressor: Added knee support.

[js at users.alioth.debian.org]

The following commit has been merged in the master branch:
commit ee56776ccd6ac527b7e9e5783dc12fb869df5d8a
Author: Thor Harald Johansen <thj at thj.no>
Date:   Fri Oct 31 03:38:23 2008 +0100

    + Compressor: Added knee support.

diff --git a/src/calf/modules_dev.h b/src/calf/modules_dev.h
index aad5b7e..b785886 100644
--- a/src/calf/modules_dev.h
+++ b/src/calf/modules_dev.h
@@ -28,7 +28,7 @@ namespace synth {
 class compressor_audio_module: public null_audio_module {
 public:
     enum { in_count = 2, out_count = 2, support_midi = false, rt_capable = true };
-    enum { param_threshold, param_ratio, param_attack, param_release, param_makeup, param_compression, param_count };
+    enum { param_threshold, param_ratio, param_attack, param_release, param_makeup, param_knee, param_compression, param_count };
 
     static const char *port_names[in_count + out_count];
     static synth::ladspa_plugin_info plugin_info;
@@ -48,6 +48,7 @@ public:
         float attack_coeff = 1 / (*params[param_attack] * srate / 4000);
         float release_coeff = 1 / (*params[param_release] * srate / 4000);
         float makeup = *params[param_makeup];
+        bool knee = *params[param_knee] > 0.5;
 
         if(params[param_compression] != NULL) {
             *params[param_compression] = aim;
@@ -61,6 +62,14 @@ public:
                     target /= ratio;
                     target += threshold;
                     target /= asample;
+                } else if(asample > 0 && knee) {
+                    target = asample - threshold;
+                    target /= ratio;
+                    target += threshold;
+                    float knee1 = pow(asample / threshold, 3);
+                    float knee2 = 1 - knee1;
+                    target = target * knee1 + asample * knee2;
+                    target /= asample;
                 } else {
                     target = 1;
                 }
diff --git a/src/modules.cpp b/src/modules.cpp
index f5ec068..c80441c 100644
--- a/src/modules.cpp
+++ b/src/modules.cpp
@@ -179,7 +179,8 @@ parameter_properties compressor_audio_module::param_props[] = {
     { 10,     1, 2000, 0, PF_FLOAT | PF_SCALE_LOG | PF_CTL_KNOB | PF_UNIT_MSEC, NULL, "attack", "Attack" },
     { 100,    1, 2000, 0, PF_FLOAT | PF_SCALE_LOG | PF_CTL_KNOB | PF_UNIT_MSEC, NULL, "release", "Release" },
     { 1,      1, 12,   0, PF_FLOAT | PF_SCALE_GAIN | PF_CTL_KNOB | PF_UNIT_DB, NULL, "makeup", "Makeup Gain" },
-    { 0, 0.015625, 1,    0, PF_FLOAT | PF_SCALE_GAIN | PF_CTL_METER | PF_CTLO_LABEL | PF_CTLO_REVERSE | PF_UNIT_DB | PF_PROP_OUTPUT | PF_PROP_OPTIONAL, NULL, "compression", "Compression" }
+    { 0,      0,  1,   0, PF_BOOL | PF_CTL_TOGGLE, NULL, "knee", "Knee" },
+    { 0, 0.03125, 1,    0, PF_FLOAT | PF_SCALE_GAIN | PF_CTL_METER | PF_CTLO_LABEL | PF_CTLO_REVERSE | PF_UNIT_DB | PF_PROP_OUTPUT | PF_PROP_OPTIONAL, NULL, "compression", "Compression" }
 };
 
 synth::ladspa_plugin_info compressor_audio_module::plugin_info = { 0x8502, "Compressor", "Calf Compressor", "Thor Harald Johansen", synth::calf_copyright_info, "CompressorPlugin" };

-- 
calf audio plugins packaging