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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sw=2 sts=2 et cindent: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "WAVDecoder.h"
#include "AudioSampleFormat.h"
#include "mozilla/SyncRunnable.h"
using mp4_demuxer::ByteReader;
namespace mozilla {
int16_t
DecodeALawSample(uint8_t aValue)
{
aValue = aValue ^ 0x55;
int8_t sign = (aValue & 0x80) ? -1 : 1;
uint8_t exponent = (aValue & 0x70) >> 4;
uint8_t mantissa = aValue & 0x0F;
int16_t sample = mantissa << 4;
switch (exponent) {
case 0:
sample += 8;
break;
case 1:
sample += 0x108;
break;
default:
sample += 0x108;
sample <<= exponent - 1;
}
return sign * sample;
}
int16_t
DecodeULawSample(uint8_t aValue)
{
aValue = aValue ^ 0xFF;
int8_t sign = (aValue & 0x80) ? -1 : 1;
uint8_t exponent = (aValue & 0x70) >> 4;
uint8_t mantissa = aValue & 0x0F;
int16_t sample = (33 + 2 * mantissa) * (2 << (exponent + 1)) - 33;
return sign * sample;
}
WaveDataDecoder::WaveDataDecoder(const CreateDecoderParams& aParams)
: mInfo(aParams.AudioConfig())
, mCallback(aParams.mCallback)
{
}
void
WaveDataDecoder::Shutdown()
{
}
RefPtr<MediaDataDecoder::InitPromise>
WaveDataDecoder::Init()
{
return InitPromise::CreateAndResolve(TrackInfo::kAudioTrack, __func__);
}
void
WaveDataDecoder::Input(MediaRawData* aSample)
{
MediaResult rv = DoDecode(aSample);
if (NS_FAILED(rv)) {
mCallback->Error(rv);
} else {
mCallback->InputExhausted();
}
}
MediaResult
WaveDataDecoder::DoDecode(MediaRawData* aSample)
{
size_t aLength = aSample->Size();
ByteReader aReader(aSample->Data(), aLength);
int64_t aOffset = aSample->mOffset;
uint64_t aTstampUsecs = aSample->mTime;
int32_t frames = aLength * 8 / mInfo.mBitDepth / mInfo.mChannels;
AlignedAudioBuffer buffer(frames * mInfo.mChannels);
if (!buffer) {
return MediaResult(NS_ERROR_OUT_OF_MEMORY, __func__);
}
for (int i = 0; i < frames; ++i) {
for (unsigned int j = 0; j < mInfo.mChannels; ++j) {
if (mInfo.mProfile == 6) { //ALAW Data
uint8_t v = aReader.ReadU8();
int16_t decoded = DecodeALawSample(v);
buffer[i * mInfo.mChannels + j] =
IntegerToAudioSample<AudioDataValue>(decoded);
} else if (mInfo.mProfile == 7) { //ULAW Data
uint8_t v = aReader.ReadU8();
int16_t decoded = DecodeULawSample(v);
buffer[i * mInfo.mChannels + j] =
IntegerToAudioSample<AudioDataValue>(decoded);
} else { //PCM Data
if (mInfo.mBitDepth == 8) {
uint8_t v = aReader.ReadU8();
buffer[i * mInfo.mChannels + j] =
UInt8bitToAudioSample<AudioDataValue>(v);
} else if (mInfo.mBitDepth == 16) {
int16_t v = aReader.ReadLE16();
buffer[i * mInfo.mChannels + j] =
IntegerToAudioSample<AudioDataValue>(v);
} else if (mInfo.mBitDepth == 24) {
int32_t v = aReader.ReadLE24();
buffer[i * mInfo.mChannels + j] =
Int24bitToAudioSample<AudioDataValue>(v);
}
}
}
}
int64_t duration = frames / mInfo.mRate;
mCallback->Output(new AudioData(aOffset,
aTstampUsecs,
duration,
frames,
Move(buffer),
mInfo.mChannels,
mInfo.mRate));
return NS_OK;
}
void
WaveDataDecoder::Drain()
{
mCallback->DrainComplete();
}
void
WaveDataDecoder::Flush()
{
}
/* static */
bool
WaveDataDecoder::IsWave(const nsACString& aMimeType)
{
// Some WebAudio uses "audio/x-wav",
// WAVdemuxer uses "audio/wave; codecs=aNum".
return aMimeType.EqualsLiteral("audio/x-wav") ||
aMimeType.EqualsLiteral("audio/wave; codecs=1") ||
aMimeType.EqualsLiteral("audio/wave; codecs=6") ||
aMimeType.EqualsLiteral("audio/wave; codecs=7") ||
aMimeType.EqualsLiteral("audio/wave; codecs=65534");
}
} // namespace mozilla
#undef LOG
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