Files
projectm/src/libprojectM/PCM.cpp
milkdropper ac29ef99eb Not needed with debugging here. (#481)
Co-authored-by: Mischa Spiegelmock <me@mish.dev>
2021-07-04 16:35:59 +03:00

558 lines
16 KiB
C++
Executable File

/**
* projectM -- Milkdrop-esque visualisation SDK
* Copyright (C)2003-2004 projectM Team
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
* See 'LICENSE.txt' included within this release
*
*/
/**
* $Id: PCM.c,v 1.3 2006/03/13 20:35:26 psperl Exp $
*
* Takes sound data from wherever and hands it back out.
* Returns PCM Data or spectrum data, or the derivative of the PCM data
*/
#include <stdlib.h>
#include <stdio.h>
#include <math.h>
#include "Common.hpp"
#include "wipemalloc.h"
#include "fftsg.h"
#include "PCM.hpp"
#include <cassert>
// see https://github.com/projectM-visualizer/projectm/issues/161
class AutoLevel
{
private:
double level;
// accumulate sample data
size_t level_samples;
double level_sum;
double level_max;
double l0,l1,l2;
public:
AutoLevel() : level(0.01),level_samples(0),level_sum(0),level_max(0),l0(-1),l1(-1),l2(-1)
{
}
/*
* Here is where we try to do auto volume setting. Doing this here
* means that none of the code downstream (waveforms, beatdetect, etc) needs
* to worry about it.
*
* 1) Don't over react to level changes within a song
* 2) Ignore silence/gaps
*
* I don't know if it's necessary to have both sum and max, but that makes
* it easier to experiment...
*/
// This is an arbitrary number that helps control
// a) how quickly the level can change and
// b) keeps code from being affected by how the caller provides data (lot of short buffers, or fewer long buffers)
#define AUTOLEVEL_SEGMENT 4096
double updateLevel(size_t samples, double sum, double max)
{
if (sum/samples < 0.00001)
return level;
level_sum += sum;
level_max = fmax(level_max,max*1.02);
level_samples += samples;
if (level_samples >= AUTOLEVEL_SEGMENT || l0 <= 0)
{
double max_recent = fmax(fmax(l0, l1), fmax(l2, level_max));
l0 = l1; l1 = l2; l2 = level_max; level_max *= 0.95;
level_sum = level_samples = 0;
level = (l0 <= 0) ? max_recent : level * 0.96 + max_recent * 0.04;
level = fmax(level,0.0001);
}
return level;
}
};
PCM::PCM() : start(0), newsamples(0)
{
leveler = new AutoLevel();
//Allocate FFT workspace
// per rdft() documentation
// length of ip >= 2+sqrt(n) and length of w == n/2
#if FFT_LENGTH > 1024
#error update this code
#endif
w = (double *)wipemalloc(FFT_LENGTH*sizeof(double));
// see fftsg.cpp length of ip >= 2+sqrt(n/2)
// in this case n=2*FFT_LENGTH, so 34 is big enough to handle FFT_LENGTH=1024
ip = (int *)wipemalloc(34 * sizeof(int));
ip[0]=0;
memset(pcmL, 0, sizeof(pcmL));
memset(pcmR, 0, sizeof(pcmR));
memset(freqL, 0, sizeof(freqL));
memset(freqR, 0, sizeof(freqR));
memset(spectrumL, 0, sizeof(spectrumL));
memset(spectrumR, 0, sizeof(spectrumR));
}
PCM::~PCM()
{
delete leveler;
free(w);
free(ip);
}
#include <iostream>
void PCM::addPCMfloat(const float *PCMdata, size_t samples)
{
float a,sum=0,max=0;
for (size_t i=0; i<samples; i++)
{
size_t j=(i+start)%maxsamples;
a=pcmL[j] = PCMdata[i];
pcmR[j] = PCMdata[i];
sum += fabs(a);
max = fmax(max,a);
}
start = (start+samples)%maxsamples;
newsamples += samples;
level = leveler->updateLevel(samples, sum, max);
}
/* NOTE: this method expects total samples, not samples per channel */
void PCM::addPCMfloat_2ch(const float *PCMdata, size_t count)
{
size_t samples = count/2;
float a,b,sum=0,max=0;
for (size_t i=0; i<samples; i++)
{
size_t j=(start+i)%maxsamples;
a = pcmL[j] = PCMdata[i*2];
b = pcmR[j] = PCMdata[i*2+1];
sum += fabs(a) + fabs(b);
max = fmax(fmax(max,fabs(a)),fabs(b));
}
start = (start + samples) % maxsamples;
newsamples += samples;
level = leveler->updateLevel(samples, sum/2, max);
}
void PCM::addPCM16Data(const short* pcm_data, size_t samples)
{
float a, b, sum = 0, max = 0;
for (size_t i = 0; i < samples; ++i)
{
size_t j = (i + start) % maxsamples;
a = pcmL[j] = (pcm_data[i * 2 + 0] / 16384.0);
b = pcmR[j] = (pcm_data[i * 2 + 1] / 16384.0);
sum += fabs(a) + fabs(b);
max = fmax(fmax(max, a), b);
}
start = (start + samples) % maxsamples;
newsamples += samples;
level = leveler->updateLevel(samples, sum/2, max);
}
void PCM::addPCM16(const short PCMdata[2][512])
{
const int samples=512;
float a,b,sum=0,max=0;
for (size_t i=0;i<samples;i++)
{
size_t j=(i+start) % maxsamples;
a=pcmL[j]=(PCMdata[0][i]/16384.0);
b=pcmR[j]=(PCMdata[1][i]/16384.0);
sum += fabs(a) + fabs(b);
max = fmax(fmax(max,a),b);
}
start = (start+samples) % maxsamples;
newsamples += samples;
level = leveler->updateLevel(samples, sum/2, max);
}
void PCM::addPCM8(const unsigned char PCMdata[2][1024])
{
const int samples=1024;
float a,b,sum=0,max=0;
for (size_t i=0; i<samples; i++)
{
size_t j= (i+start) % maxsamples;
a=pcmL[j]=(((float)PCMdata[0][i] - 128.0) / 64 );
b=pcmR[j]=(((float)PCMdata[1][i] - 128.0) / 64 );
sum += fabs(a) + fabs(b);
max = fmax(fmax(max,a),b);
}
start = (start + samples) % maxsamples;
newsamples += samples;
level = leveler->updateLevel(samples, sum/2, max);
}
void PCM::addPCM8_512(const unsigned char PCMdata[2][512])
{
const size_t samples=512;
float a,b,sum=0,max=0;
for (size_t i=0; i<samples; i++)
{
size_t j = (i+start) % maxsamples;
a=pcmL[j]=(((float)PCMdata[0][i] - 128.0 ) / 64 );
b=pcmR[j]=(((float)PCMdata[1][i] - 128.0 ) / 64 );
sum += fabs(a) + fabs(b);
max = fmax(fmax(max,a),b);
}
start = (start + samples) % maxsamples;
newsamples += samples;
level = leveler->updateLevel(samples, sum/2, max);
}
// puts sound data requested at provided pointer
//
// samples is number of PCM samples to return
// smoothing is the smoothing coefficient
// returned values are normalized from -1 to 1
void PCM::getPCM(float *data, CHANNEL channel, size_t samples, float smoothing)
{
assert(channel == 0 || channel == 1);
if (0==smoothing)
{
_copyPCM(data, channel, samples);
return;
}
// since we've already got the freq data laying around, let's use that for smoothing
_updateFFT();
// copy
double freq[FFT_LENGTH*2];
double *from = channel==0 ? freqL : freqR;
for (int i=0 ; i<FFT_LENGTH*2 ; i++)
freq[i] = from[i];
// The visible effects ramp up as you smoothing value gets close to 1.0 (consistent with milkdrop2)
if (1==0) // gaussian
{
// precompute constant:
double k = -1.0 / ((1 - smoothing) * (1 - smoothing) * FFT_LENGTH * FFT_LENGTH);
for (int i = 1; i < FFT_LENGTH; i++)
{
float g = pow(2.718281828459045, i * i * k);
freq[i * 2] *= g;
freq[i * 2 + 1] *= g;
}
freq[1] *= pow(2.718281828459045, FFT_LENGTH*FFT_LENGTH*k);
}
else
{
// butterworth
// this might be slightly faster to compute. pow() is expensive
double k = 1.0 / ((1 - smoothing) * (1 - smoothing) * FFT_LENGTH * FFT_LENGTH);
for (int i = 1; i < FFT_LENGTH; i++)
{
float b = 1.0 / (1.0 + (i * i * k));
freq[i * 2] *= b;
freq[i * 2 + 1] *= b;
}
freq[1] *= 1.0 / (1.0 + (FFT_LENGTH*FFT_LENGTH*k));
}
// inverse fft
rdft(FFT_LENGTH*2, -1, freq, ip, w);
for (size_t j = 0; j < FFT_LENGTH*2; j++)
freq[j] *= 1.0 / FFT_LENGTH;
// copy out with zero-padding if necessary
size_t count = samples<FFT_LENGTH ? samples : FFT_LENGTH;
for (size_t i=0 ; i<count ; i++)
data[i] = freq[i%(FFT_LENGTH*2)];
for (size_t i=count ; i<samples ; i++)
data[i] = 0;
}
/* NOTE: Still don't have real support for smoothing parameter, but this gets close to the milkdrop2 default look */
void PCM::getSpectrum(float *data, CHANNEL channel, size_t samples, float smoothing)
{
assert(channel == 0 || channel == 1);
_updateFFT();
float *spectrum = channel == 0 ? spectrumL : spectrumR;
if (smoothing == 0)
{
size_t count = samples <= FFT_LENGTH ? samples : FFT_LENGTH;
for (size_t i = 0; i < count; i++)
data[i] = spectrum[i];
for (size_t i = count; i < samples; i++)
data[0] = 0;
}
else
{
float l2 = 0, l1 =0 , c = 0, r1, r2;
r1 = spectrum[0]; r2 = spectrum[0+1];
for (size_t i = 0; i < samples; i++)
{
l2 = l1;
l1 = c;
c = r1;
r1 = r2;
r2 = (i + 2) >= samples ? 0 : spectrum[i + 2];
data[i] = (l2 + 4 * l1 + 6 * c + 4 * r1 + r2) / 16.0;
}
}
}
void PCM::_updateFFT()
{
if (newsamples > 0)
{
_updateFFT(0);
_updateFFT(1);
newsamples = 0;
}
}
void PCM::_updateFFT(size_t channel)
{
assert(channel == 0 || channel == 1);
double *freq = channel==0 ? freqL : freqR;
_copyPCM(freq, channel, FFT_LENGTH*2);
rdft(FFT_LENGTH*2, 1, freq, ip, w);
// compute magnitude data (m^2 actually)
float *spectrum = channel==0 ? spectrumL : spectrumR;
for (size_t i=1 ; i<FFT_LENGTH ; i++)
{
double m2 = (freq[i * 2] * freq[i * 2] + freq[i * 2 + 1] * freq[i * 2 + 1]);
spectrum[i-1] = m2 * ((double)i)/FFT_LENGTH;
}
spectrum[FFT_LENGTH-1] = freq[1] * freq[1];
}
inline double constrain(double a, double mn, double mx)
{
return a>mx ? mx : a<mn ? mn : a;
}
// pull data from circular buffer
void PCM::_copyPCM(float *to, int channel, size_t count)
{
assert(channel == 0 || channel == 1);
assert(count < maxsamples);
const float *from = channel==0 ? pcmL : pcmR;
const double volume = 1.0 / level;
for (size_t i=0, pos=start ; i<count ; i++)
{
if (pos==0)
pos = maxsamples;
to[i] = from[--pos] * volume;
}
}
void PCM::_copyPCM(double *to, int channel, size_t count)
{
assert(channel == 0 || channel == 1);
const float *from = channel==0 ? pcmL : pcmR;
const double volume = 1.0 / level;
for (size_t i=0, pos=start ; i<count ; i++)
{
if (pos==0)
pos = maxsamples;
to[i] = from[--pos] * volume;
}
}
//Free stuff
void PCM::freePCM()
{
free(ip);
free(w);
ip = NULL;
w = NULL;
}
// TESTS
#include "TestRunner.hpp"
#ifndef NDEBUG
#define TEST(cond) if (!verify(__FILE__ ": " #cond,cond)) return false
#define TEST2(str,cond) if (!verify(str,cond)) return false
struct PCMTest : public Test
{
PCMTest() : Test("PCMTest")
{}
bool eq(float a, float b)
{
return fabs(a-b) < (fabs(a)+fabs(b) + 1)/1000.0f;
}
public:
/* smoke test for each addPCM method */
bool test_addpcm()
{
PCM pcm;
// mono float
{
const size_t samples = 301;
float *data = new float[samples];
for (size_t i = 0; i < samples; i++)
data[i] = ((float) i) / (samples - 1);
for (size_t i = 0; i < 10; i++)
pcm.addPCMfloat(data, samples);
float *copy = new float[samples];
pcm.level = 1.0;
pcm._copyPCM(copy, 0, samples);
for (size_t i = 0; i < samples; i++)
TEST(eq(copy[i],((float)samples - 1 - i) / (samples - 1)));
pcm._copyPCM(copy, 1, samples);
for (size_t i = 0; i < samples; i++)
TEST(eq(copy[i], ((float)samples - 1 - i) / (samples - 1)));
free(data);
free(copy);
}
// float_2ch
{
const size_t samples = 301;
float *data = new float[samples*2];
for (size_t i = 0; i < samples; i++)
{
data[i*2] = ((float) i) / (samples - 1);
data[i*2+1] = 1.0-data[i*2] ;
}
for (size_t i = 0; i < 10; i++)
pcm.addPCMfloat_2ch(data, samples*2);
float *copy0 = new float[samples];
float *copy1 = new float[samples];
pcm.level = 1;
pcm._copyPCM(copy0, 0, samples);
pcm._copyPCM(copy1, 1, samples);
for (size_t i = 0; i < samples; i++)
TEST(eq(1.0,copy0[i]+copy1[i]));
free(data);
free(copy0);
free(copy1);
}
// void PCM::addPCM16Data(const short* pcm_data, size_t samples)
// void PCM::addPCM16(const short PCMdata[2][512])
// void PCM::addPCM8(const unsigned char PCMdata[2][1024])
// void PCM::addPCM8_512(const unsigned char PCMdata[2][512])
return true;
}
bool test_fft()
{
PCM pcm;
// low frequency
{
const size_t samples = 1024;
float *data = new float[samples * 2];
for (size_t i = 0; i < samples; i++)
{
float f = 2 * 3.141592653589793 * ((double) i) / (samples - 1);
data[i * 2] = sin(f);
data[i * 2 + 1] = sin(f + 1.0); // out of phase
}
pcm.addPCMfloat_2ch(data, samples * 2);
pcm.addPCMfloat_2ch(data, samples * 2);
float *freq0 = new float[FFT_LENGTH];
float *freq1 = new float[FFT_LENGTH];
pcm.level = 1.0;
pcm.getSpectrum(freq0, CHANNEL_0, FFT_LENGTH, 0.0);
pcm.getSpectrum(freq1, CHANNEL_1, FFT_LENGTH, 0.0);
// freq0 and freq1 should be equal
for (size_t i = 0; i < FFT_LENGTH; i++)
TEST(eq(freq0[i], freq1[i]));
TEST(freq0[0] > 500);
for (size_t i = 1; i < FFT_LENGTH; i++)
TEST(freq0[i] < 0.1);
free(data);
free(freq0);
free(freq1);
}
// high frequency
{
const size_t samples = 2;
float data[4] = {1.0,0.0,0.0,1.0};
for (size_t i = 0; i < 1024; i++)
pcm.addPCMfloat_2ch(data, samples * 2);
float *freq0 = new float[FFT_LENGTH];
float *freq1 = new float[FFT_LENGTH];
pcm.level = 1.0;
pcm.getSpectrum(freq0, CHANNEL_0, FFT_LENGTH, 0.0);
pcm.getSpectrum(freq1, CHANNEL_1, FFT_LENGTH, 0.0);
// freq0 and freq1 should be equal
for (size_t i = 0; i < FFT_LENGTH; i++)
TEST(eq(freq0[i], freq1[i]));
for (size_t i=0 ; i<FFT_LENGTH-1 ; i++)
TEST(0==freq0[i]);
TEST(freq0[FFT_LENGTH-1] > 100000);
free(freq0);
free(freq1);
}
return true;
}
bool test() override
{
TEST(test_addpcm());
TEST(test_fft());
return true;
}
};
Test* PCM::test()
{
return new PCMTest();
}
#else
Test* PCM::test()
{
return nullptr;
}
#endif