1 files changed, 0 insertions, 171 deletions
diff --git a/externals/oboe/src/flowgraph/resampler/MultiChannelResampler.cpp b/externals/oboe/src/flowgraph/resampler/MultiChannelResampler.cpp
deleted file mode 100644
index 245b669db4..0000000000
--- a/externals/oboe/src/flowgraph/resampler/MultiChannelResampler.cpp
+++ /dev/null
@@ -1,171 +0,0 @@
-/*
- * Copyright 2019 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#include <math.h>
-
-#include "IntegerRatio.h"
-#include "LinearResampler.h"
-#include "MultiChannelResampler.h"
-#include "PolyphaseResampler.h"
-#include "PolyphaseResamplerMono.h"
-#include "PolyphaseResamplerStereo.h"
-#include "SincResampler.h"
-#include "SincResamplerStereo.h"
-
-using namespace RESAMPLER_OUTER_NAMESPACE::resampler;
-
-MultiChannelResampler::MultiChannelResampler(const MultiChannelResampler::Builder &builder)
-        : mNumTaps(builder.getNumTaps())
-        , mX(static_cast<size_t>(builder.getChannelCount())
-                * static_cast<size_t>(builder.getNumTaps()) * 2)
-        , mSingleFrame(builder.getChannelCount())
-        , mChannelCount(builder.getChannelCount())
-        {
-    // Reduce sample rates to the smallest ratio.
-    // For example 44100/48000 would become 147/160.
-    IntegerRatio ratio(builder.getInputRate(), builder.getOutputRate());
-    ratio.reduce();
-    mNumerator = ratio.getNumerator();
-    mDenominator = ratio.getDenominator();
-    mIntegerPhase = mDenominator; // so we start with a write needed
-}
-
-// static factory method
-MultiChannelResampler *MultiChannelResampler::make(int32_t channelCount,
-                                                   int32_t inputRate,
-                                                   int32_t outputRate,
-                                                   Quality quality) {
-    Builder builder;
-    builder.setInputRate(inputRate);
-    builder.setOutputRate(outputRate);
-    builder.setChannelCount(channelCount);
-
-    switch (quality) {
-        case Quality::Fastest:
-            builder.setNumTaps(2);
-            break;
-        case Quality::Low:
-            builder.setNumTaps(4);
-            break;
-        case Quality::Medium:
-        default:
-            builder.setNumTaps(8);
-            break;
-        case Quality::High:
-            builder.setNumTaps(16);
-            break;
-        case Quality::Best:
-            builder.setNumTaps(32);
-            break;
-    }
-
-    // Set the cutoff frequency so that we do not get aliasing when down-sampling.
-    if (inputRate > outputRate) {
-        builder.setNormalizedCutoff(kDefaultNormalizedCutoff);
-    }
-    return builder.build();
-}
-
-MultiChannelResampler *MultiChannelResampler::Builder::build() {
-    if (getNumTaps() == 2) {
-        // Note that this does not do low pass filteringh.
-        return new LinearResampler(*this);
-    }
-    IntegerRatio ratio(getInputRate(), getOutputRate());
-    ratio.reduce();
-    bool usePolyphase = (getNumTaps() * ratio.getDenominator()) <= kMaxCoefficients;
-    if (usePolyphase) {
-        if (getChannelCount() == 1) {
-            return new PolyphaseResamplerMono(*this);
-        } else if (getChannelCount() == 2) {
-            return new PolyphaseResamplerStereo(*this);
-        } else {
-            return new PolyphaseResampler(*this);
-        }
-    } else {
-        // Use less optimized resampler that uses a float phaseIncrement.
-        // TODO mono resampler
-        if (getChannelCount() == 2) {
-            return new SincResamplerStereo(*this);
-        } else {
-            return new SincResampler(*this);
-        }
-    }
-}
-
-void MultiChannelResampler::writeFrame(const float *frame) {
-    // Move cursor before write so that cursor points to last written frame in read.
-    if (--mCursor < 0) {
-        mCursor = getNumTaps() - 1;
-    }
-    float *dest = &mX[static_cast<size_t>(mCursor) * static_cast<size_t>(getChannelCount())];
-    int offset = getNumTaps() * getChannelCount();
-    for (int channel = 0; channel < getChannelCount(); channel++) {
-        // Write twice so we avoid having to wrap when reading.
-        dest[channel] = dest[channel + offset] = frame[channel];
-    }
-}
-
-float MultiChannelResampler::sinc(float radians) {
-    if (fabsf(radians) < 1.0e-9f) return 1.0f;   // avoid divide by zero
-    return sinf(radians) / radians;   // Sinc function
-}
-
-// Generate coefficients in the order they will be used by readFrame().
-// This is more complicated but readFrame() is called repeatedly and should be optimized.
-void MultiChannelResampler::generateCoefficients(int32_t inputRate,
-                                              int32_t outputRate,
-                                              int32_t numRows,
-                                              double phaseIncrement,
-                                              float normalizedCutoff) {
-    mCoefficients.resize(static_cast<size_t>(getNumTaps()) * static_cast<size_t>(numRows));
-    int coefficientIndex = 0;
-    double phase = 0.0; // ranges from 0.0 to 1.0, fraction between samples
-    // Stretch the sinc function for low pass filtering.
-    const float cutoffScaler = (outputRate < inputRate)
-             ? (normalizedCutoff * (float)outputRate / inputRate)
-             : 1.0f; // Do not filter when upsampling.
-    const int numTapsHalf = getNumTaps() / 2; // numTaps must be even.
-    const float numTapsHalfInverse = 1.0f / numTapsHalf;
-    for (int i = 0; i < numRows; i++) {
-        float tapPhase = phase - numTapsHalf;
-        float gain = 0.0; // sum of raw coefficients
-        int gainCursor = coefficientIndex;
-        for (int tap = 0; tap < getNumTaps(); tap++) {
-            float radians = tapPhase * M_PI;
-
-#if MCR_USE_KAISER
-            float window = mKaiserWindow(tapPhase * numTapsHalfInverse);
-#else
-            float window = mCoshWindow(static_cast<double>(tapPhase) * numTapsHalfInverse);
-#endif
-            float coefficient = sinc(radians * cutoffScaler) * window;
-            mCoefficients.at(coefficientIndex++) = coefficient;
-            gain += coefficient;
-            tapPhase += 1.0;
-        }
-        phase += phaseIncrement;
-        while (phase >= 1.0) {
-            phase -= 1.0;
-        }
-
-        // Correct for gain variations.
-        float gainCorrection = 1.0 / gain; // normalize the gain
-        for (int tap = 0; tap < getNumTaps(); tap++) {
-            mCoefficients.at(gainCursor + tap) *= gainCorrection;
-        }
-    }
-}