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/* //device/servers/AudioFlinger/AudioCoefInterpolator.cpp
**
** Copyright 2008, 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 <string.h>
#include <cutils/compiler.h>
#include "AudioCoefInterpolator.h"
namespace android {
AudioCoefInterpolator::AudioCoefInterpolator(size_t nInDims,
const size_t inDims[],
size_t nOutDims,
const audio_coef_t * table) {
mNumInDims = nInDims;
memcpy(mInDims, inDims, nInDims * sizeof(size_t));
mNumOutDims = nOutDims;
mTable = table;
// Initialize offsets array
size_t dim = nInDims - 1;
mInDimOffsets[nInDims - 1] = nOutDims;
while (dim-- > 0) {
mInDimOffsets[dim] = mInDimOffsets[dim + 1] * mInDims[dim + 1];
}
}
void AudioCoefInterpolator::getCoef(const int intCoord[], uint32_t fracCoord[],
audio_coef_t out[]) {
size_t index = 0;
size_t dim = mNumInDims;
while (dim-- > 0) {
if (CC_UNLIKELY(intCoord[dim] < 0)) {
fracCoord[dim] = 0;
} else if (CC_UNLIKELY(intCoord[dim] >= (int)mInDims[dim] - 1)) {
fracCoord[dim] = 0;
index += mInDimOffsets[dim] * (mInDims[dim] - 1);
} else {
index += mInDimOffsets[dim] * intCoord[dim];
}
}
getCoefRecurse(index, fracCoord, out, 0);
}
void AudioCoefInterpolator::getCoefRecurse(size_t index,
const uint32_t fracCoord[],
audio_coef_t out[], size_t dim) {
if (dim == mNumInDims) {
memcpy(out, mTable + index, mNumOutDims * sizeof(audio_coef_t));
} else {
getCoefRecurse(index, fracCoord, out, dim + 1);
if (CC_LIKELY(fracCoord != 0)) {
audio_coef_t tempCoef[MAX_OUT_DIMS];
getCoefRecurse(index + mInDimOffsets[dim], fracCoord, tempCoef,
dim + 1);
size_t d = mNumOutDims;
while (d-- > 0) {
out[d] = interp(out[d], tempCoef[d], fracCoord[dim]);
}
}
}
}
audio_coef_t AudioCoefInterpolator::interp(audio_coef_t lo, audio_coef_t hi,
uint32_t frac) {
int64_t delta = static_cast<int64_t>(hi-lo) * frac;
return lo + static_cast<audio_coef_t> (delta >> 32);
}
}