/* Copyright 2008-2011 David Robillard 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 . */ #include "mdaDither.h" #include #include #include 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 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 ! }