Adding upstream version 1:115.7.0.upstream/1%115.7.0upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 222 insertions, 0 deletions

diff --git a/media/libsoundtouch/src/AAFilter.cpp b/media/libsoundtouch/src/AAFilter.cpp
new file mode 100644
index 0000000000..3fd4e9fe6d
--- /dev/null
+++ b/media/libsoundtouch/src/AAFilter.cpp
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+////////////////////////////////////////////////////////////////////////////////
+///
+/// FIR low-pass (anti-alias) filter with filter coefficient design routine and
+/// MMX optimization. 
+/// 
+/// Anti-alias filter is used to prevent folding of high frequencies when 
+/// transposing the sample rate with interpolation.
+///
+/// Author        : Copyright (c) Olli Parviainen
+/// Author e-mail : oparviai 'at' iki.fi
+/// SoundTouch WWW: http://www.surina.net/soundtouch
+///
+////////////////////////////////////////////////////////////////////////////////
+//
+// License :
+//
+//  SoundTouch audio processing library
+//  Copyright (c) Olli Parviainen
+//
+//  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
+//
+////////////////////////////////////////////////////////////////////////////////
+
+#include <memory.h>
+#include <assert.h>
+#include <math.h>
+#include <stdlib.h>
+#include "AAFilter.h"
+#include "FIRFilter.h"
+
+using namespace soundtouch;
+
+#define PI       M_PI
+#define TWOPI    (2 * PI)
+
+// define this to save AA filter coefficients to a file
+// #define _DEBUG_SAVE_AAFILTER_COEFFICIENTS   1
+
+#ifdef _DEBUG_SAVE_AAFILTER_COEFFICIENTS
+    #include <stdio.h>
+
+    static void _DEBUG_SAVE_AAFIR_COEFFS(SAMPLETYPE *coeffs, int len)
+    {
+        FILE *fptr = fopen("aa_filter_coeffs.txt", "wt");
+        if (fptr == NULL) return;
+
+        for (int i = 0; i < len; i ++)
+        {
+            double temp = coeffs[i];
+            fprintf(fptr, "%lf\n", temp);
+        }
+        fclose(fptr);
+    }
+
+#else
+    #define _DEBUG_SAVE_AAFIR_COEFFS(x, y)
+#endif
+
+/*****************************************************************************
+ *
+ * Implementation of the class 'AAFilter'
+ *
+ *****************************************************************************/
+
+AAFilter::AAFilter(uint len)
+{
+    pFIR = FIRFilter::newInstance();
+    cutoffFreq = 0.5;
+    setLength(len);
+}
+
+
+AAFilter::~AAFilter()
+{
+    delete pFIR;
+}
+
+
+// Sets new anti-alias filter cut-off edge frequency, scaled to
+// sampling frequency (nyquist frequency = 0.5).
+// The filter will cut frequencies higher than the given frequency.
+void AAFilter::setCutoffFreq(double newCutoffFreq)
+{
+    cutoffFreq = newCutoffFreq;
+    calculateCoeffs();
+}
+
+
+// Sets number of FIR filter taps
+void AAFilter::setLength(uint newLength)
+{
+    length = newLength;
+    calculateCoeffs();
+}
+
+
+// Calculates coefficients for a low-pass FIR filter using Hamming window
+void AAFilter::calculateCoeffs()
+{
+    uint i;
+    double cntTemp, temp, tempCoeff,h, w;
+    double wc;
+    double scaleCoeff, sum;
+    double *work;
+    SAMPLETYPE *coeffs;
+
+    assert(length >= 2);
+    assert(length % 4 == 0);
+    assert(cutoffFreq >= 0);
+    assert(cutoffFreq <= 0.5);
+
+    work = new double[length];
+    coeffs = new SAMPLETYPE[length];
+
+    wc = 2.0 * PI * cutoffFreq;
+    tempCoeff = TWOPI / (double)length;
+
+    sum = 0;
+    for (i = 0; i < length; i ++) 
+    {
+        cntTemp = (double)i - (double)(length / 2);
+
+        temp = cntTemp * wc;
+        if (temp != 0) 
+        {
+            h = sin(temp) / temp;                     // sinc function
+        } 
+        else 
+        {
+            h = 1.0;
+        }
+        w = 0.54 + 0.46 * cos(tempCoeff * cntTemp);       // hamming window
+
+        temp = w * h;
+        work[i] = temp;
+
+        // calc net sum of coefficients 
+        sum += temp;
+    }
+
+    // ensure the sum of coefficients is larger than zero
+    assert(sum > 0);
+
+    // ensure we've really designed a lowpass filter...
+    assert(work[length/2] > 0);
+    assert(work[length/2 + 1] > -1e-6);
+    assert(work[length/2 - 1] > -1e-6);
+
+    // Calculate a scaling coefficient in such a way that the result can be
+    // divided by 16384
+    scaleCoeff = 16384.0f / sum;
+
+    for (i = 0; i < length; i ++) 
+    {
+        temp = work[i] * scaleCoeff;
+        // scale & round to nearest integer
+        temp += (temp >= 0) ? 0.5 : -0.5;
+        // ensure no overfloods
+        assert(temp >= -32768 && temp <= 32767);
+        coeffs[i] = (SAMPLETYPE)temp;
+    }
+
+    // Set coefficients. Use divide factor 14 => divide result by 2^14 = 16384
+    pFIR->setCoefficients(coeffs, length, 14);
+
+    _DEBUG_SAVE_AAFIR_COEFFS(coeffs, length);
+
+    delete[] work;
+    delete[] coeffs;
+}
+
+
+// Applies the filter to the given sequence of samples. 
+// Note : The amount of outputted samples is by value of 'filter length' 
+// smaller than the amount of input samples.
+uint AAFilter::evaluate(SAMPLETYPE *dest, const SAMPLETYPE *src, uint numSamples, uint numChannels) const
+{
+    return pFIR->evaluate(dest, src, numSamples, numChannels);
+}
+
+
+/// Applies the filter to the given src & dest pipes, so that processed amount of
+/// samples get removed from src, and produced amount added to dest 
+/// Note : The amount of outputted samples is by value of 'filter length' 
+/// smaller than the amount of input samples.
+uint AAFilter::evaluate(FIFOSampleBuffer &dest, FIFOSampleBuffer &src) const
+{
+    SAMPLETYPE *pdest;
+    const SAMPLETYPE *psrc;
+    uint numSrcSamples;
+    uint result;
+    int numChannels = src.getChannels();
+
+    assert(numChannels == dest.getChannels());
+
+    numSrcSamples = src.numSamples();
+    psrc = src.ptrBegin();
+    pdest = dest.ptrEnd(numSrcSamples);
+    result = pFIR->evaluate(pdest, psrc, numSrcSamples, numChannels);
+    src.receiveSamples(result);
+    dest.putSamples(result);
+
+    return result;
+}
+
+
+uint AAFilter::getLength() const
+{
+    return pFIR->getLength();
+}