Add reverb DSP.

audio/filters/Makefile

@@ -55,8 +55,8 @@ else
    DYLIB = dll
 endif
 
-CC      := $(compiler)
-CXX     := $(subst CC,++,$(compiler)) -std=gnu++0x
+CC      := $(compiler) -Wall
+CXX     := $(subst CC,++,$(compiler)) -std=gnu++0x -Wall
 flags   := -fPIC $(extra_flags)
 asflags := -fPIC  $(extra_flags)
 objects :=

audio/filters/Phaser.dsp

@@ -2,10 +2,10 @@ filters = 1
 filter0 = phaser
 
 # Defaults.
-# lfo_freq = 0.4
-# lfo_start_phase = 0.0
-# feedback = 0.0
-# depth = 0.4
-# dry_wet = 0.5
-# stages = 2
+# phaser_lfo_freq = 0.4
+# phaser_lfo_start_phase = 0.0
+# phaser_feedback = 0.0
+# phaser_depth = 0.4
+# phaser_dry_wet = 0.5
+# phaser_stages = 2
 

audio/filters/Reverb.dsp

@@ -0,0 +1,10 @@
+filters = 1
+filter0 = reverb
+
+# Defaults.
+# reverb_drytime = 0.43
+# reverb_wettime = 0.4
+# reverb_damping = 0.8
+# reverb_roomwidth = 0.56
+# reverb_roomsize = 0.56
+

audio/filters/WahWah.dsp

@@ -2,9 +2,9 @@ filters = 1
 filter0 = wahwah
 
 # Defaults.
-# lfo_freq = 1.5
-# lfo_start_phase = 0.0
-# freq_offset = 0.3
-# depth = 0.7
-# resonance = 2.5
+# wahwah_lfo_freq = 1.5
+# wahwah_lfo_start_phase = 0.0
+# wahwah_freq_offset = 0.3
+# wahwah_depth = 0.7
+# wahwah_resonance = 2.5
 

audio/filters/reverb.c

@@ -0,0 +1,315 @@
+/*  RetroArch - A frontend for libretro.
+ *  Copyright (C) 2010-2014 - Hans-Kristian Arntzen
+ *  Copyright (C) 2014 - Brad Miller
+ *
+ *  RetroArch is free software: you can redistribute it and/or modify it under the terms
+ *  of the GNU General Public License as published by the Free Software Found-
+ *  ation, either version 3 of the License, or (at your option) any later version.
+ *
+ *  RetroArch is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+ *  without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
+ *  PURPOSE.  See the GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along with RetroArch.
+ *  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "dspfilter.h"
+#include <math.h>
+#include <stdlib.h>
+#include <string.h>
+
+struct comb
+{
+   float *buffer;
+   unsigned bufsize;
+   unsigned bufidx;
+
+   float feedback;
+   float filterstore;
+   float damp1, damp2;
+};
+
+static inline float comb_process(struct comb *c, float input)
+{
+   float output = c->buffer[c->bufidx];
+   c->filterstore = (output * c->damp2) + (c->filterstore * c->damp1);
+
+   c->buffer[c->bufidx] = input + (c->filterstore * c->feedback);
+
+   c->bufidx++;
+   if (c->bufidx >= c->bufsize)
+      c->bufidx = 0;
+
+   return output;
+}
+
+struct allpass
+{
+   float *buffer;
+   float feedback;
+   unsigned bufsize;
+   unsigned bufidx;
+};
+
+static inline float allpass_process(struct allpass *a, float input)
+{
+   float bufout = a->buffer[a->bufidx];
+   float output = -input + bufout;
+   a->buffer[a->bufidx] = input + bufout * a->feedback;
+
+   a->bufidx++;
+   if (a->bufidx >= a->bufsize)
+      a->bufidx = 0;
+
+   return output;
+}
+
+#define numcombs 8
+#define numallpasses 4
+static const float muted = 0;
+static const float fixedgain = 0.015f;
+static const float scalewet = 3;
+static const float scaledry = 2;
+static const float scaledamp = 0.4f;
+static const float scaleroom = 0.28f;
+static const float offsetroom = 0.7f;
+static const float initialroom = 0.5f;
+static const float initialdamp = 0.5f;
+static const float initialwet = 1.0f / 3.0f;
+static const float initialdry = 0;
+static const float initialwidth = 1;
+static const float initialmode = 0;
+static const float freezemode = 0.5f;
+
+#define combtuningL1 1116
+#define combtuningL2 1188
+#define combtuningL3 1277
+#define combtuningL4 1356
+#define combtuningL5 1422
+#define combtuningL6 1491
+#define combtuningL7 1557
+#define combtuningL8 1617
+#define allpasstuningL1 556
+#define allpasstuningL2 441
+#define allpasstuningL3 341
+#define allpasstuningL4 225
+
+struct revmodel
+{
+   struct comb combL[numcombs];
+   struct allpass allpassL[numallpasses];
+
+   float bufcombL1[combtuningL1];
+   float bufcombL2[combtuningL2];
+   float bufcombL3[combtuningL3];
+   float bufcombL4[combtuningL4];
+   float bufcombL5[combtuningL5];
+   float bufcombL6[combtuningL6];
+   float bufcombL7[combtuningL7];
+   float bufcombL8[combtuningL8];
+
+   float bufallpassL1[allpasstuningL1];
+   float bufallpassL2[allpasstuningL2];
+   float bufallpassL3[allpasstuningL3];
+   float bufallpassL4[allpasstuningL4];
+
+   float gain;
+   float roomsize, roomsize1;
+   float damp, damp1;
+   float wet, wet1, wet2;
+   float dry;
+   float width;
+   float mode;
+};
+
+static float revmodel_process(struct revmodel *rev, float in)
+{
+   int i;
+   float mono_out = 0.0f;
+   float mono_in = in;
+   float input = mono_in * rev->gain;
+   for (i = 0; i < numcombs; i++)
+      mono_out += comb_process(&rev->combL[i], input);
+
+   for (i = 0; i < numallpasses; i++)
+      mono_out = allpass_process(&rev->allpassL[i], mono_out);
+
+   return mono_in * rev->dry + mono_out * rev->wet1;
+}
+
+static void revmodel_update(struct revmodel *rev)
+{
+   int i;
+   rev->wet1 = rev->wet * (rev->width / 2.0f + 0.5f);
+
+   if (rev->mode >= freezemode)
+   {
+      rev->roomsize1 = 1.0f;
+      rev->damp1 = 0.0f;
+      rev->gain = muted;
+   }
+   else
+   {
+      rev->roomsize1 = rev->roomsize;
+      rev->damp1 = rev->damp;
+      rev->gain = fixedgain;
+   }
+
+   for (i = 0; i < numcombs; i++)
+   {
+      rev->combL[i].feedback = rev->roomsize1;
+      rev->combL[i].damp1 = rev->damp1;
+      rev->combL[i].damp2 = 1.0f - rev->damp1;
+   }
+}
+
+static void revmodel_setroomsize(struct revmodel *rev, float value)
+{
+   rev->roomsize = value * scaleroom + offsetroom;
+   revmodel_update(rev);
+}
+
+static void revmodel_setdamp(struct revmodel *rev, float value)
+{
+   rev->damp = value * scaledamp;
+   revmodel_update(rev);
+}
+
+static void revmodel_setwet(struct revmodel *rev, float value)
+{
+   rev->wet = value * scalewet;
+   revmodel_update(rev);
+}
+
+static void revmodel_setdry(struct revmodel *rev, float value)
+{
+   rev->dry = value * scaledry;
+   revmodel_update(rev);
+}
+
+static void revmodel_setwidth(struct revmodel *rev, float value)
+{
+   rev->width = value;
+   revmodel_update(rev);
+}
+
+static void revmodel_setmode(struct revmodel *rev, float value)
+{
+   rev->mode = value;
+   revmodel_update(rev);
+}
+
+static void revmodel_init(struct revmodel *rev)
+{
+   rev->combL[0].buffer = rev->bufcombL1; rev->combL[0].bufsize = combtuningL1;
+   rev->combL[1].buffer = rev->bufcombL2; rev->combL[1].bufsize = combtuningL2;
+   rev->combL[2].buffer = rev->bufcombL3; rev->combL[2].bufsize = combtuningL3;
+   rev->combL[3].buffer = rev->bufcombL4; rev->combL[3].bufsize = combtuningL4;
+   rev->combL[4].buffer = rev->bufcombL5; rev->combL[4].bufsize = combtuningL5;
+   rev->combL[5].buffer = rev->bufcombL6; rev->combL[5].bufsize = combtuningL6;
+   rev->combL[6].buffer = rev->bufcombL7; rev->combL[6].bufsize = combtuningL7;
+   rev->combL[7].buffer = rev->bufcombL8; rev->combL[7].bufsize = combtuningL8;
+
+   rev->allpassL[0].buffer = rev->bufallpassL1; rev->allpassL[0].bufsize = allpasstuningL1;
+   rev->allpassL[1].buffer = rev->bufallpassL2; rev->allpassL[1].bufsize = allpasstuningL2;
+   rev->allpassL[2].buffer = rev->bufallpassL3; rev->allpassL[2].bufsize = allpasstuningL3;
+   rev->allpassL[3].buffer = rev->bufallpassL4; rev->allpassL[3].bufsize = allpasstuningL4;
+
+   rev->allpassL[0].feedback = 0.5f;
+   rev->allpassL[1].feedback = 0.5f;
+   rev->allpassL[2].feedback = 0.5f;
+   rev->allpassL[3].feedback = 0.5f;
+
+   revmodel_setwet(rev, initialwet);
+   revmodel_setroomsize(rev, initialroom);
+   revmodel_setdry(rev, initialdry);
+   revmodel_setdamp(rev, initialdamp);
+   revmodel_setwidth(rev, initialwidth);
+   revmodel_setmode(rev, initialmode);
+}
+
+struct reverb_data
+{
+   struct revmodel left, right;
+};
+
+static void reverb_free(void *data)
+{
+   free(data);
+}
+
+static void reverb_process(void *data, struct dspfilter_output *output,
+      const struct dspfilter_input *input)
+{
+   unsigned i;
+   struct reverb_data *rev = (struct reverb_data*)data;
+
+   output->samples = input->samples;
+   output->frames  = input->frames;
+   float *out = output->samples;
+
+   for (i = 0; i < input->frames; i++, out += 2)
+   {
+      float in[2] = { out[0], out[1] };
+
+      out[0] = revmodel_process(&rev->left, in[0]);
+      out[1] = revmodel_process(&rev->right, in[1]);
+   }
+}
+
+static void *reverb_init(const struct dspfilter_info *info,
+      const struct dspfilter_config *config, void *userdata)
+{
+   struct reverb_data *rev = (struct reverb_data*)calloc(1, sizeof(*rev));
+   if (!rev)
+      return NULL;
+
+   float drytime, wettime, damping, roomwidth, roomsize;
+   config->get_float(userdata, "drytime", &drytime, 0.43f);
+   config->get_float(userdata, "wettime", &wettime, 0.4f);
+   config->get_float(userdata, "damping", &damping, 0.8f);
+   config->get_float(userdata, "roomwidth", &roomwidth, 0.56f);
+   config->get_float(userdata, "roomsize", &roomsize, 0.56f);
+
+   revmodel_init(&rev->left);
+   revmodel_init(&rev->right);
+
+   revmodel_setdamp(&rev->left, damping);
+   revmodel_setdry(&rev->left, drytime);
+   revmodel_setwet(&rev->left, wettime);
+   revmodel_setwidth(&rev->left, roomwidth);
+   revmodel_setroomsize(&rev->left, roomsize);
+
+   revmodel_setdamp(&rev->right, damping);
+   revmodel_setdry(&rev->right, drytime);
+   revmodel_setwet(&rev->right, wettime);
+   revmodel_setwidth(&rev->right, roomwidth);
+   revmodel_setroomsize(&rev->right, roomsize);
+
+   return rev;
+}
+
+static const struct dspfilter_implementation reverb_plug = {
+   reverb_init,
+   reverb_process,
+   reverb_free,
+
+   DSPFILTER_API_VERSION,
+   "Reverb",
+   "reverb",
+};
+
+#ifdef HAVE_FILTERS_BUILTIN
+#define dspfilter_get_implementation reverb_dspfilter_get_implementation
+#endif
+
+const struct dspfilter_implementation *dspfilter_get_implementation(dspfilter_simd_mask_t mask)
+{
+   (void)mask;
+   return &reverb_plug;
+}
+
+#undef dspfilter_get_implementation
+
+