diff options
Diffstat (limited to 'src/filters/renderer/MpcAudioRenderer/SoundTouch/source/BPMDetect.cpp')
| -rw-r--r-- | src/filters/renderer/MpcAudioRenderer/SoundTouch/source/BPMDetect.cpp | 113 |
1 files changed, 55 insertions, 58 deletions
diff --git a/src/filters/renderer/MpcAudioRenderer/SoundTouch/source/BPMDetect.cpp b/src/filters/renderer/MpcAudioRenderer/SoundTouch/source/BPMDetect.cpp index 6609f55c5..405f514bf 100644 --- a/src/filters/renderer/MpcAudioRenderer/SoundTouch/source/BPMDetect.cpp +++ b/src/filters/renderer/MpcAudioRenderer/SoundTouch/source/BPMDetect.cpp @@ -26,10 +26,10 @@ ///
////////////////////////////////////////////////////////////////////////////////
//
-// Last changed : $Date: 2008-12-25 19:54:41 +0200 (Thu, 25 Dec 2008) $
+// Last changed : $Date: 2009-02-21 18:00:14 +0200 (Sat, 21 Feb 2009) $
// File revision : $Revision: 4 $
//
-// $Id: BPMDetect.cpp 43 2008-12-25 17:54:41Z oparviai $
+// $Id: BPMDetect.cpp 63 2009-02-21 16:00:14Z oparviai $
//
////////////////////////////////////////////////////////////////////////////////
//
@@ -66,8 +66,6 @@ using namespace soundtouch; #define INPUT_BLOCK_SAMPLES 2048
#define DECIMATED_BLOCK_SAMPLES 256
-typedef unsigned short ushort;
-
/// decay constant for calculating RMS volume sliding average approximation
/// (time constant is about 10 sec)
const float avgdecay = 0.99986f;
@@ -77,18 +75,13 @@ const float avgnorm = (1 - avgdecay); -BPMDetect::BPMDetect(int numChannels, int sampleRate)
+BPMDetect::BPMDetect(int numChannels, int aSampleRate)
{
- xcorr = NULL;
-
- buffer = new FIFOSampleBuffer();
+ this->sampleRate = aSampleRate;
+ this->channels = numChannels;
decimateSum = 0;
decimateCount = 0;
- decimateBy = 0;
-
- this->sampleRate = sampleRate;
- this->channels = numChannels;
envelopeAccu = 0;
@@ -103,7 +96,26 @@ BPMDetect::BPMDetect(int numChannels, int sampleRate) RMSVolumeAccu = (0.092f * 0.092f) / avgnorm;
#endif
- init(numChannels, sampleRate);
+ // choose decimation factor so that result is approx. 500 Hz
+ decimateBy = sampleRate / 500;
+ assert(decimateBy > 0);
+ assert(INPUT_BLOCK_SAMPLES < decimateBy * DECIMATED_BLOCK_SAMPLES);
+
+ // Calculate window length & starting item according to desired min & max bpms
+ windowLen = (60 * sampleRate) / (decimateBy * MIN_BPM);
+ windowStart = (60 * sampleRate) / (decimateBy * MAX_BPM);
+
+ assert(windowLen > windowStart);
+
+ // allocate new working objects
+ xcorr = new float[windowLen];
+ memset(xcorr, 0, windowLen * sizeof(float));
+
+ // allocate processing buffer
+ buffer = new FIFOSampleBuffer();
+ // we do processing in mono mode
+ buffer->setChannels(1);
+ buffer->clear();
}
@@ -115,7 +127,9 @@ BPMDetect::~BPMDetect() }
-/// low-pass filter & decimate to about 500 Hz. return number of outputted samples.
+
+/// convert to mono, low-pass filter & decimate to about 500 Hz.
+/// return number of outputted samples.
///
/// Decimation is used to remove the unnecessary frequencies and thus to reduce
/// the amount of data needed to be processed as calculating autocorrelation
@@ -130,17 +144,25 @@ int BPMDetect::decimate(SAMPLETYPE *dest, const SAMPLETYPE *src, int numsamples) int count, outcount;
LONG_SAMPLETYPE out;
- assert(decimateBy != 0);
+ assert(channels > 0);
+ assert(decimateBy > 0);
outcount = 0;
for (count = 0; count < numsamples; count ++)
{
- decimateSum += src[count];
+ int j;
+
+ // convert to mono and accumulate
+ for (j = 0; j < channels; j ++)
+ {
+ decimateSum += src[j];
+ }
+ src += j;
decimateCount ++;
if (decimateCount >= decimateBy)
{
// Store every Nth sample only
- out = (LONG_SAMPLETYPE)(decimateSum / decimateBy);
+ out = (LONG_SAMPLETYPE)(decimateSum / (decimateBy * channels));
decimateSum = 0;
decimateCount = 0;
#ifdef INTEGER_SAMPLES
@@ -231,27 +253,27 @@ void BPMDetect::calcEnvelope(SAMPLETYPE *samples, int numsamples) -void BPMDetect::inputSamples(SAMPLETYPE *samples, int numSamples)
+void BPMDetect::inputSamples(const SAMPLETYPE *samples, int numSamples)
{
SAMPLETYPE decimated[DECIMATED_BLOCK_SAMPLES];
- // convert from stereo to mono if necessary
- if (channels == 2)
+ // iterate so that max INPUT_BLOCK_SAMPLES processed per iteration
+ while (numSamples > 0)
{
- int i;
+ int block;
+ int decSamples;
- for (i = 0; i < numSamples; i ++)
- {
- samples[i] = (samples[i * 2] + samples[i * 2 + 1]) / 2;
- }
- }
-
- // decimate
- numSamples = decimate(decimated, samples, numSamples);
+ block = (numSamples > INPUT_BLOCK_SAMPLES) ? INPUT_BLOCK_SAMPLES : numSamples;
+
+ // decimate. note that converts to mono at the same time
+ decSamples = decimate(decimated, samples, block);
+ samples += block * channels;
+ numSamples -= block;
- // envelope new samples and add them to buffer
- calcEnvelope(decimated, numSamples);
- buffer->putSamples(decimated, numSamples);
+ // envelope new samples and add them to buffer
+ calcEnvelope(decimated, decSamples);
+ buffer->putSamples(decimated, decSamples);
+ }
// when the buffer has enought samples for processing...
if ((int)buffer->numSamples() > windowLen)
@@ -259,7 +281,7 @@ void BPMDetect::inputSamples(SAMPLETYPE *samples, int numSamples) int processLength;
// how many samples are processed
- processLength = buffer->numSamples() - windowLen;
+ processLength = (int)buffer->numSamples() - windowLen;
// ... calculate autocorrelations for oldest samples...
updateXCorr(processLength);
@@ -269,31 +291,6 @@ void BPMDetect::inputSamples(SAMPLETYPE *samples, int numSamples) }
-void BPMDetect::init(int numChannels, int sampleRate)
-{
- this->sampleRate = sampleRate;
-
- // choose decimation factor so that result is approx. 500 Hz
- decimateBy = sampleRate / 500;
- assert(decimateBy > 0);
- assert(INPUT_BLOCK_SAMPLES < decimateBy * DECIMATED_BLOCK_SAMPLES);
-
- // Calculate window length & starting item according to desired min & max bpms
- windowLen = (60 * sampleRate) / (decimateBy * MIN_BPM);
- windowStart = (60 * sampleRate) / (decimateBy * MAX_BPM);
-
- assert(windowLen > windowStart);
-
- // allocate new working objects
- xcorr = new float[windowLen];
- memset(xcorr, 0, windowLen * sizeof(float));
-
- // we do processing in mono mode
- buffer->setChannels(1);
- buffer->clear();
-}
-
-
float BPMDetect::getBpm()
{
|