ebiten/audio/internal/oboe/oboe_flowgraph_resampler_LinearResampler_android.cpp

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1.6 KiB
C++
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/*
* 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 "oboe_flowgraph_resampler_LinearResampler_android.h"
using namespace resampler;
LinearResampler::LinearResampler(const MultiChannelResampler::Builder &builder)
: MultiChannelResampler(builder) {
mPreviousFrame = std::make_unique<float[]>(getChannelCount());
mCurrentFrame = std::make_unique<float[]>(getChannelCount());
}
void LinearResampler::writeFrame(const float *frame) {
memcpy(mPreviousFrame.get(), mCurrentFrame.get(), sizeof(float) * getChannelCount());
memcpy(mCurrentFrame.get(), frame, sizeof(float) * getChannelCount());
}
void LinearResampler::readFrame(float *frame) {
float *previous = mPreviousFrame.get();
float *current = mCurrentFrame.get();
float phase = (float) getIntegerPhase() / mDenominator;
// iterate across samples in the frame
for (int channel = 0; channel < getChannelCount(); channel++) {
float f0 = *previous++;
float f1 = *current++;
*frame++ = f0 + (phase * (f1 - f0));
}
}