1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/media/libsoundtouch/src/InterpolateCubic.cpp Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,200 @@
1.4 +////////////////////////////////////////////////////////////////////////////////
1.5 +///
1.6 +/// Cubic interpolation routine.
1.7 +///
1.8 +/// Author : Copyright (c) Olli Parviainen
1.9 +/// Author e-mail : oparviai 'at' iki.fi
1.10 +/// SoundTouch WWW: http://www.surina.net/soundtouch
1.11 +///
1.12 +////////////////////////////////////////////////////////////////////////////////
1.13 +//
1.14 +// $Id: InterpolateCubic.cpp 179 2014-01-06 18:41:42Z oparviai $
1.15 +//
1.16 +////////////////////////////////////////////////////////////////////////////////
1.17 +//
1.18 +// License :
1.19 +//
1.20 +// SoundTouch audio processing library
1.21 +// Copyright (c) Olli Parviainen
1.22 +//
1.23 +// This library is free software; you can redistribute it and/or
1.24 +// modify it under the terms of the GNU Lesser General Public
1.25 +// License as published by the Free Software Foundation; either
1.26 +// version 2.1 of the License, or (at your option) any later version.
1.27 +//
1.28 +// This library is distributed in the hope that it will be useful,
1.29 +// but WITHOUT ANY WARRANTY; without even the implied warranty of
1.30 +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
1.31 +// Lesser General Public License for more details.
1.32 +//
1.33 +// You should have received a copy of the GNU Lesser General Public
1.34 +// License along with this library; if not, write to the Free Software
1.35 +// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
1.36 +//
1.37 +////////////////////////////////////////////////////////////////////////////////
1.38 +
1.39 +#include <stddef.h>
1.40 +#include <math.h>
1.41 +#include "InterpolateCubic.h"
1.42 +#include "STTypes.h"
1.43 +
1.44 +using namespace soundtouch;
1.45 +
1.46 +// cubic interpolation coefficients
1.47 +static const float _coeffs[]=
1.48 +{ -0.5f, 1.0f, -0.5f, 0.0f,
1.49 + 1.5f, -2.5f, 0.0f, 1.0f,
1.50 + -1.5f, 2.0f, 0.5f, 0.0f,
1.51 + 0.5f, -0.5f, 0.0f, 0.0f};
1.52 +
1.53 +
1.54 +InterpolateCubic::InterpolateCubic()
1.55 +{
1.56 + fract = 0;
1.57 +}
1.58 +
1.59 +
1.60 +void InterpolateCubic::resetRegisters()
1.61 +{
1.62 + fract = 0;
1.63 +}
1.64 +
1.65 +
1.66 +/// Transpose mono audio. Returns number of produced output samples, and
1.67 +/// updates "srcSamples" to amount of consumed source samples
1.68 +int InterpolateCubic::transposeMono(SAMPLETYPE *pdest,
1.69 + const SAMPLETYPE *psrc,
1.70 + int &srcSamples)
1.71 +{
1.72 + int i;
1.73 + int srcSampleEnd = srcSamples - 4;
1.74 + int srcCount = 0;
1.75 +
1.76 + i = 0;
1.77 + while (srcCount < srcSampleEnd)
1.78 + {
1.79 + float out;
1.80 + const float x3 = 1.0f;
1.81 + const float x2 = (float)fract; // x
1.82 + const float x1 = x2*x2; // x^2
1.83 + const float x0 = x1*x2; // x^3
1.84 + float y0, y1, y2, y3;
1.85 +
1.86 + assert(fract < 1.0);
1.87 +
1.88 + y0 = _coeffs[0] * x0 + _coeffs[1] * x1 + _coeffs[2] * x2 + _coeffs[3] * x3;
1.89 + y1 = _coeffs[4] * x0 + _coeffs[5] * x1 + _coeffs[6] * x2 + _coeffs[7] * x3;
1.90 + y2 = _coeffs[8] * x0 + _coeffs[9] * x1 + _coeffs[10] * x2 + _coeffs[11] * x3;
1.91 + y3 = _coeffs[12] * x0 + _coeffs[13] * x1 + _coeffs[14] * x2 + _coeffs[15] * x3;
1.92 +
1.93 + out = y0 * psrc[0] + y1 * psrc[1] + y2 * psrc[2] + y3 * psrc[3];
1.94 +
1.95 + pdest[i] = (SAMPLETYPE)out;
1.96 + i ++;
1.97 +
1.98 + // update position fraction
1.99 + fract += rate;
1.100 + // update whole positions
1.101 + int whole = (int)fract;
1.102 + fract -= whole;
1.103 + psrc += whole;
1.104 + srcCount += whole;
1.105 + }
1.106 + srcSamples = srcCount;
1.107 + return i;
1.108 +}
1.109 +
1.110 +
1.111 +/// Transpose stereo audio. Returns number of produced output samples, and
1.112 +/// updates "srcSamples" to amount of consumed source samples
1.113 +int InterpolateCubic::transposeStereo(SAMPLETYPE *pdest,
1.114 + const SAMPLETYPE *psrc,
1.115 + int &srcSamples)
1.116 +{
1.117 + int i;
1.118 + int srcSampleEnd = srcSamples - 4;
1.119 + int srcCount = 0;
1.120 +
1.121 + i = 0;
1.122 + while (srcCount < srcSampleEnd)
1.123 + {
1.124 + const float x3 = 1.0f;
1.125 + const float x2 = (float)fract; // x
1.126 + const float x1 = x2*x2; // x^2
1.127 + const float x0 = x1*x2; // x^3
1.128 + float y0, y1, y2, y3;
1.129 + float out0, out1;
1.130 +
1.131 + assert(fract < 1.0);
1.132 +
1.133 + y0 = _coeffs[0] * x0 + _coeffs[1] * x1 + _coeffs[2] * x2 + _coeffs[3] * x3;
1.134 + y1 = _coeffs[4] * x0 + _coeffs[5] * x1 + _coeffs[6] * x2 + _coeffs[7] * x3;
1.135 + y2 = _coeffs[8] * x0 + _coeffs[9] * x1 + _coeffs[10] * x2 + _coeffs[11] * x3;
1.136 + y3 = _coeffs[12] * x0 + _coeffs[13] * x1 + _coeffs[14] * x2 + _coeffs[15] * x3;
1.137 +
1.138 + out0 = y0 * psrc[0] + y1 * psrc[2] + y2 * psrc[4] + y3 * psrc[6];
1.139 + out1 = y0 * psrc[1] + y1 * psrc[3] + y2 * psrc[5] + y3 * psrc[7];
1.140 +
1.141 + pdest[2*i] = (SAMPLETYPE)out0;
1.142 + pdest[2*i+1] = (SAMPLETYPE)out1;
1.143 + i ++;
1.144 +
1.145 + // update position fraction
1.146 + fract += rate;
1.147 + // update whole positions
1.148 + int whole = (int)fract;
1.149 + fract -= whole;
1.150 + psrc += 2*whole;
1.151 + srcCount += whole;
1.152 + }
1.153 + srcSamples = srcCount;
1.154 + return i;
1.155 +}
1.156 +
1.157 +
1.158 +/// Transpose multi-channel audio. Returns number of produced output samples, and
1.159 +/// updates "srcSamples" to amount of consumed source samples
1.160 +int InterpolateCubic::transposeMulti(SAMPLETYPE *pdest,
1.161 + const SAMPLETYPE *psrc,
1.162 + int &srcSamples)
1.163 +{
1.164 + int i;
1.165 + int srcSampleEnd = srcSamples - 4;
1.166 + int srcCount = 0;
1.167 +
1.168 + i = 0;
1.169 + while (srcCount < srcSampleEnd)
1.170 + {
1.171 + const float x3 = 1.0f;
1.172 + const float x2 = (float)fract; // x
1.173 + const float x1 = x2*x2; // x^2
1.174 + const float x0 = x1*x2; // x^3
1.175 + float y0, y1, y2, y3;
1.176 +
1.177 + assert(fract < 1.0);
1.178 +
1.179 + y0 = _coeffs[0] * x0 + _coeffs[1] * x1 + _coeffs[2] * x2 + _coeffs[3] * x3;
1.180 + y1 = _coeffs[4] * x0 + _coeffs[5] * x1 + _coeffs[6] * x2 + _coeffs[7] * x3;
1.181 + y2 = _coeffs[8] * x0 + _coeffs[9] * x1 + _coeffs[10] * x2 + _coeffs[11] * x3;
1.182 + y3 = _coeffs[12] * x0 + _coeffs[13] * x1 + _coeffs[14] * x2 + _coeffs[15] * x3;
1.183 +
1.184 + for (int c = 0; c < numChannels; c ++)
1.185 + {
1.186 + float out;
1.187 + out = y0 * psrc[c] + y1 * psrc[c + numChannels] + y2 * psrc[c + 2 * numChannels] + y3 * psrc[c + 3 * numChannels];
1.188 + pdest[0] = (SAMPLETYPE)out;
1.189 + pdest ++;
1.190 + }
1.191 + i ++;
1.192 +
1.193 + // update position fraction
1.194 + fract += rate;
1.195 + // update whole positions
1.196 + int whole = (int)fract;
1.197 + fract -= whole;
1.198 + psrc += numChannels*whole;
1.199 + srcCount += whole;
1.200 + }
1.201 + srcSamples = srcCount;
1.202 + return i;
1.203 +}
