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diff --git a/src/mdaDither.cpp b/src/mdaDither.cpp
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+/*
+ Copyright 2008-2011 David Robillard <http://drobilla.net>
+ Copyright 1999-2000 Paul Kellett (Maxim Digital Audio)
+
+ This 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 Foundation, either version 3 of the License,
+ or (at your option) any later version.
+
+ This software 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 this software. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "mdaDither.h"
+
+#include <math.h>
+#include <stdlib.h>
+#include <float.h>
+
+AudioEffect *createEffectInstance(audioMasterCallback audioMaster)
+{
+ return new mdaDither(audioMaster);
+}
+
+mdaDither::mdaDither(audioMasterCallback audioMaster) : AudioEffectX(audioMaster, 1, 5) // programs, parameters
+{
+ //inits here!
+ fParam0 = 0.50f; //bits
+ fParam1 = 0.88f; //dither (off, rect, tri, hp-tri, hp-tri-2ndOrderShaped)
+ fParam2 = 0.50f; //dither level
+ fParam3 = 0.50f; //dc trim
+ fParam4 = 0.00f; //zoom (8 bit dither and fade audio out)
+
+ sh1 = sh2 = sh3 = sh4 = 0.0f;
+ rnd1 = rnd3 = 0;
+
+ setNumInputs(2);
+ setNumOutputs(2);
+ setUniqueID("mdaDither"); // identify here
+ DECLARE_LVZ_DEPRECATED(canMono) ();
+ canProcessReplacing();
+ strcpy(programName, "Dither & Noise Shaping");
+
+ setParameter(0, 0.5f);
+}
+
+bool mdaDither::getProductString(char* text) { strcpy(text, "MDA Dither"); return true; }
+bool mdaDither::getVendorString(char* text) { strcpy(text, "mda"); return true; }
+bool mdaDither::getEffectName(char* name) { strcpy(name, "Dither"); return true; }
+
+void mdaDither::setParameter(int32_t index, float value)
+{
+ switch(index)
+ {
+ case 0: fParam0 = value; break;
+ case 1: fParam1 = value; break;
+ case 2: fParam2 = value; break;
+ case 3: fParam3 = value; break;
+ case 4: fParam4 = value; break;
+ }
+ //calcs here
+ gain = 1.0f;
+ bits = 8.0f + 2.0f * (float)floor(8.9f * fParam0);
+
+ if(fParam4>0.1f) //zoom to 6 bit & fade out audio
+ {
+ wlen = 32.0f;
+ gain = (1.0f - fParam4); gain*=gain;
+ }
+ else wlen = (float)pow(2.0f, bits - 1.0f); //word length in quanta
+
+ //Using WaveLab 2.01 (unity gain) as a reference:
+ // 16-bit output is (int)floor(floating_point_value*32768.0f)
+
+ offs = (4.0f * fParam3 - 1.5f) / wlen; //DC offset (plus 0.5 to round dither not truncate)
+ dith = 2.0f * fParam2 / (wlen * (float)32767);
+ shap=0.0f;
+
+ switch((int32_t)(fParam1*3.9)) //dither mode
+ {
+ case 0: dith = 0.0f; break; //off
+ case 3: shap = 0.5f; break; //noise shaping
+ default: break; //tri, hp-tri
+ }
+}
+
+mdaDither::~mdaDither()
+{
+}
+
+void mdaDither::suspend()
+{
+ //no need to zero buffers here as effect so small
+}
+
+void mdaDither::setProgramName(char *name)
+{
+ strcpy(programName, name);
+}
+
+void mdaDither::getProgramName(char *name)
+{
+ strcpy(name, programName);
+}
+
+bool mdaDither::getProgramNameIndexed (int32_t category, int32_t index, char* name)
+{
+ if (index == 0)
+ {
+ strcpy(name, programName);
+ return true;
+ }
+ return false;
+}
+
+float mdaDither::getParameter(int32_t index)
+{
+ float v=0;
+
+ switch(index)
+ {
+ case 0: v = fParam0; break;
+ case 1: v = fParam1; break;
+ case 2: v = fParam2; break;
+ case 3: v = fParam3; break;
+ case 4: v = fParam4; break;
+ }
+ return v;
+}
+
+void mdaDither::getParameterName(int32_t index, char *label)
+{
+ switch(index)
+ {
+ case 0: strcpy(label, "Word Len"); break;
+ case 1: strcpy(label, "Dither"); break;
+ case 2: strcpy(label, "Dith Amp"); break;
+ case 3: strcpy(label, "DC Trim"); break;
+ case 4: strcpy(label, "Zoom"); break;
+ }
+}
+
+#include <stdio.h>
+static void int2strng(int32_t value, char *string) { sprintf(string, "%d", value); }
+static void float2strng(float value, char *string) { sprintf(string, "%.2f", value); }
+
+void mdaDither::getParameterDisplay(int32_t index, char *text)
+{
+ switch(index)
+ {
+ case 0: int2strng((int32_t)bits, text); break;
+ case 1: switch((int32_t)(fParam1*3.9))
+ { case 0: strcpy(text, "OFF"); break;
+ case 1: strcpy(text, "TRI"); break;
+ case 2: strcpy(text, "HP-TRI"); break;
+ default: strcpy(text, "N.SHAPE"); break;
+ } break;
+ case 2: float2strng(4.0f * fParam2, text); break;
+ case 3: float2strng(4.0f * fParam3 - 2.0f, text); break;
+ case 4: if(fParam4>0.1f)
+ if(gain<0.0001f) strcpy(text, "-80");
+ else int2strng((int32_t)(20.0 * log10(gain)), text);
+ else strcpy(text, "OFF");
+ break;
+ }
+}
+
+void mdaDither::getParameterLabel(int32_t index, char *label)
+{
+ switch(index)
+ {
+ case 0: strcpy(label, "Bits"); break;
+ case 1: strcpy(label, ""); break;
+ case 2: strcpy(label, "lsb"); break;
+ case 3: strcpy(label, "lsb"); break;
+ case 4: strcpy(label, "dB"); break;
+ }
+}
+
+//--------------------------------------------------------------------------------
+// process
+
+void mdaDither::process(float **inputs, float **outputs, int32_t sampleFrames)
+{
+ float *in1 = inputs[0];
+ float *in2 = inputs[1];
+ float *out1 = outputs[0];
+ float *out2 = outputs[1];
+ float a, b, aa, bb, c, d;
+ float sl=shap, s1=sh1, s2=sh2, s3=sh3, s4=sh4; //shaping level, buffers
+ float dl=dith; //dither level
+ float o=offs, w=wlen, wi=1.0f/wlen; //DC offset, word length & inverse
+ float g=gain; //gain for Zoom mode
+ int32_t r1=rnd1, r2, r3=rnd3, r4; //random numbers for dither
+ int32_t m=1; //dither mode
+ if((int32_t)(fParam1 * 3.9f)==1) m=0; //what is the fastest if(?)
+
+ --in1;
+ --in2;
+ --out1;
+ --out2;
+
+ while(--sampleFrames >= 0)
+ {
+ a = *++in1;
+ b = *++in2;
+ c = out1[1];
+ d = out2[1];
+
+ r2=r1; r4=r3;
+ if(m==0) { r4=rand() & 0x7FFF; r2=(r4 & 0x7F)<<8; }
+ r1=rand() & 0x7FFF; r3=(r1 & 0x7F)<<8;
+
+ a = g * a + sl * (s1 + s1 - s2);
+ aa = a + o + dl * (float)(r1 - r2);
+ if(aa<0.0f) aa-=wi;
+ aa = wi * (float)(int32_t)(w * aa);
+ s2 = s1;
+ s1 = a - aa;
+
+ b = g * b + sl * (s3 + s3 - s4);
+ bb = b + o + dl * (float)(r3 - r4);
+ if(bb<0.0f) bb-=wi;
+ bb = wi * (float)(int32_t)(w * bb);
+ s4 = s3;
+ s3 = b - bb;
+
+ *++out1 = c + aa;
+ *++out2 = d + bb;
+ }
+
+ sh1=s1; sh2=s2; sh3=s3; sh4=s4;
+ rnd1=r1; rnd3=r3;
+}
+
+void mdaDither::processReplacing(float **inputs, float **outputs, int32_t sampleFrames)
+{
+ float *in1 = inputs[0];
+ float *in2 = inputs[1];
+ float *out1 = outputs[0];
+ float *out2 = outputs[1];
+ float a, b, aa, bb;
+ float sl=shap, s1=sh1, s2=sh2, s3=sh3, s4=sh4; //shaping level, buffers
+ float dl=dith; //dither level
+ float o=offs, w=wlen, wi=1.0f/wlen; //DC offset, word length & inverse
+ float g=gain; //gain for Zoom mode
+ int32_t r1=rnd1, r2, r3=rnd3, r4; //random numbers for dither
+ int32_t m=1; //dither mode
+ if((int32_t)(fParam1 * 3.9f)==1) m=0; //what is the fastest if(?)
+
+ --in1;
+ --in2;
+ --out1;
+ --out2;
+
+ while(--sampleFrames >= 0)
+ {
+ a = *++in1;
+ b = *++in2;
+
+ r2=r1; r4=r3; //HP-TRI dither (also used when noise shaping)
+ if(m==0) { r4=rand() & 0x7FFF; r2=(r4 & 0x7F)<<8; } //TRI dither
+ r1=rand() & 0x7FFF; r3=(r1 & 0x7F)<<8; //Assumes RAND_MAX=32767?
+
+ a = g * a + sl * (s1 + s1 - s2); //target level + error feedback
+ aa = a + o + dl * (float)(r1 - r2); // + offset + dither
+ if(aa<0.0f) aa-=wi; //(int32_t) truncates towards zero!
+ aa = wi * (float)(int32_t)(w * aa); //truncate
+ s2 = s1;
+ s1 = a - aa; //error feedback: 2nd order noise shaping
+
+ b = g * b + sl * (s3 + s3 - s4);
+ bb = b + o + dl * (float)(r3 - r4);
+ if(bb<0.0f) bb-=wi;
+ bb = wi * (float)(int32_t)(w * bb);
+ s4 = s3;
+ s3 = b - bb;
+
+ *++out1 = aa;
+ *++out2 = bb;
+ }
+
+ sh1=s1; sh2=s2; sh3=s3; sh4=s4; //doesn't actually matter if these are
+ rnd1=r1; rnd3=r3; //saved or not as effect is so small !
+}
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