scummvm/audio/decoders/flac.cpp
2021-12-26 18:48:43 +01:00

741 lines
28 KiB
C++

/* ScummVM - Graphic Adventure Engine
*
* ScummVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
// Disable symbol overrides for FILE as that is used in FLAC headers
#define FORBIDDEN_SYMBOL_EXCEPTION_FILE
#include "audio/decoders/flac.h"
#ifdef USE_FLAC
#include "common/debug.h"
#include "common/stream.h"
#include "common/textconsole.h"
#include "common/util.h"
#include "audio/audiostream.h"
#define FLAC__NO_DLL // that MS-magic gave me headaches - just link the library you like
#include <FLAC/export.h>
// check if we have FLAC >= 1.1.3; LEGACY_FLAC code can be removed once FLAC-1.1.3 propagates everywhere
#if !defined(FLAC_API_VERSION_CURRENT) || FLAC_API_VERSION_CURRENT < 8
#define LEGACY_FLAC
#else
#undef LEGACY_FLAC
#endif
#ifdef LEGACY_FLAC
// Before FLAC 1.1.3, we needed to use the stream decoder API.
#include <FLAC/seekable_stream_decoder.h>
typedef uint FLAC_size_t;
#else
// With FLAC 1.1.3, the stream decoder API was merged into the regular
// stream API. In order to stay compatible with older FLAC versions, we
// simply add some typedefs and #ifdefs to map between the old and new API.
// We use the typedefs (instead of only #defines) in order to somewhat
// improve the readability of the code.
#include <FLAC/stream_decoder.h>
typedef size_t FLAC_size_t;
// Add aliases for the old names
typedef FLAC__StreamDecoderState FLAC__SeekableStreamDecoderState;
typedef FLAC__StreamDecoderReadStatus FLAC__SeekableStreamDecoderReadStatus;
typedef FLAC__StreamDecoderSeekStatus FLAC__SeekableStreamDecoderSeekStatus;
typedef FLAC__StreamDecoderTellStatus FLAC__SeekableStreamDecoderTellStatus;
typedef FLAC__StreamDecoderLengthStatus FLAC__SeekableStreamDecoderLengthStatus;
typedef FLAC__StreamDecoder FLAC__SeekableStreamDecoder;
#endif
namespace Audio {
#pragma mark -
#pragma mark --- FLAC stream ---
#pragma mark -
static const uint MAX_OUTPUT_CHANNELS = 2;
class FLACStream : public SeekableAudioStream {
protected:
Common::SeekableReadStream *_inStream;
bool _disposeAfterUse;
::FLAC__SeekableStreamDecoder *_decoder;
/** Header of the stream */
FLAC__StreamMetadata_StreamInfo _streaminfo;
/** index + 1(!) of the last sample to be played */
FLAC__uint64 _lastSample;
/** total play time */
Timestamp _length;
/** true if the last sample was decoded from the FLAC-API - there might still be data in the buffer */
bool _lastSampleWritten;
typedef int16 SampleType;
enum { BUFTYPE_BITS = 16 };
enum {
// Maximal buffer size. According to the FLAC format specification, the block size is
// a 16 bit value (in fact it seems the maximal block size is 32768, but we play it safe).
BUFFER_SIZE = 65536
};
struct {
SampleType bufData[BUFFER_SIZE];
SampleType *bufReadPos;
uint bufFill;
} _sampleCache;
SampleType *_outBuffer;
uint _requestedSamples;
typedef void (*PFCONVERTBUFFERS)(SampleType*, const FLAC__int32*[], uint, const uint, const uint8);
PFCONVERTBUFFERS _methodConvertBuffers;
public:
FLACStream(Common::SeekableReadStream *inStream, bool dispose);
virtual ~FLACStream();
int readBuffer(int16 *buffer, const int numSamples) override;
bool isStereo() const override { return _streaminfo.channels >= 2; }
int getRate() const override { return _streaminfo.sample_rate; }
bool endOfData() const override {
// End of data is reached if there either is no valid stream data available,
// or if we reached the last sample and completely emptied the sample cache.
return _streaminfo.channels == 0 || (_lastSampleWritten && _sampleCache.bufFill == 0);
}
bool seek(const Timestamp &where) override;
Timestamp getLength() const override { return _length; }
bool isStreamDecoderReady() const { return getStreamDecoderState() == FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC; }
protected:
uint getChannels() const { return MIN<uint>(_streaminfo.channels, MAX_OUTPUT_CHANNELS); }
bool allocateBuffer(uint minSamples);
inline FLAC__StreamDecoderState getStreamDecoderState() const;
inline bool processSingleBlock();
inline bool processUntilEndOfMetadata();
bool seekAbsolute(FLAC__uint64 sample);
inline ::FLAC__SeekableStreamDecoderReadStatus callbackRead(FLAC__byte buffer[], FLAC_size_t *bytes);
inline ::FLAC__SeekableStreamDecoderSeekStatus callbackSeek(FLAC__uint64 absoluteByteOffset);
inline ::FLAC__SeekableStreamDecoderTellStatus callbackTell(FLAC__uint64 *absoluteByteOffset);
inline ::FLAC__SeekableStreamDecoderLengthStatus callbackLength(FLAC__uint64 *streamLength);
inline bool callbackEOF();
inline ::FLAC__StreamDecoderWriteStatus callbackWrite(const ::FLAC__Frame *frame, const FLAC__int32 * const buffer[]);
inline void callbackMetadata(const ::FLAC__StreamMetadata *metadata);
inline void callbackError(::FLAC__StreamDecoderErrorStatus status);
private:
static ::FLAC__SeekableStreamDecoderReadStatus callWrapRead(const ::FLAC__SeekableStreamDecoder *decoder, FLAC__byte buffer[], FLAC_size_t *bytes, void *clientData);
static ::FLAC__SeekableStreamDecoderSeekStatus callWrapSeek(const ::FLAC__SeekableStreamDecoder *decoder, FLAC__uint64 absoluteByteOffset, void *clientData);
static ::FLAC__SeekableStreamDecoderTellStatus callWrapTell(const ::FLAC__SeekableStreamDecoder *decoder, FLAC__uint64 *absoluteByteOffset, void *clientData);
static ::FLAC__SeekableStreamDecoderLengthStatus callWrapLength(const ::FLAC__SeekableStreamDecoder *decoder, FLAC__uint64 *streamLength, void *clientData);
static FLAC__bool callWrapEOF(const ::FLAC__SeekableStreamDecoder *decoder, void *clientData);
static ::FLAC__StreamDecoderWriteStatus callWrapWrite(const ::FLAC__SeekableStreamDecoder *decoder, const ::FLAC__Frame *frame, const FLAC__int32 * const buffer[], void *clientData);
static void callWrapMetadata(const ::FLAC__SeekableStreamDecoder *decoder, const ::FLAC__StreamMetadata *metadata, void *clientData);
static void callWrapError(const ::FLAC__SeekableStreamDecoder *decoder, ::FLAC__StreamDecoderErrorStatus status, void *clientData);
void setBestConvertBufferMethod();
static void convertBuffersGeneric(SampleType* bufDestination, const FLAC__int32 *inChannels[], uint numSamples, const uint numChannels, const uint8 numBits);
static void convertBuffersStereoNS(SampleType* bufDestination, const FLAC__int32 *inChannels[], uint numSamples, const uint numChannels, const uint8 numBits);
static void convertBuffersStereo8Bit(SampleType* bufDestination, const FLAC__int32 *inChannels[], uint numSamples, const uint numChannels, const uint8 numBits);
static void convertBuffersMonoNS(SampleType* bufDestination, const FLAC__int32 *inChannels[], uint numSamples, const uint numChannels, const uint8 numBits);
static void convertBuffersMono8Bit(SampleType* bufDestination, const FLAC__int32 *inChannels[], uint numSamples, const uint numChannels, const uint8 numBits);
};
FLACStream::FLACStream(Common::SeekableReadStream *inStream, bool dispose)
#ifdef LEGACY_FLAC
: _decoder(::FLAC__seekable_stream_decoder_new()),
#else
: _decoder(::FLAC__stream_decoder_new()),
#endif
_inStream(inStream),
_disposeAfterUse(dispose),
_length(0, 1000), _lastSample(0),
_outBuffer(nullptr), _requestedSamples(0), _lastSampleWritten(false),
_methodConvertBuffers(&FLACStream::convertBuffersGeneric)
{
assert(_inStream);
memset(&_streaminfo, 0, sizeof(_streaminfo));
_sampleCache.bufReadPos = nullptr;
_sampleCache.bufFill = 0;
_methodConvertBuffers = &FLACStream::convertBuffersGeneric;
bool success;
#ifdef LEGACY_FLAC
::FLAC__seekable_stream_decoder_set_read_callback(_decoder, &FLACStream::callWrapRead);
::FLAC__seekable_stream_decoder_set_seek_callback(_decoder, &FLACStream::callWrapSeek);
::FLAC__seekable_stream_decoder_set_tell_callback(_decoder, &FLACStream::callWrapTell);
::FLAC__seekable_stream_decoder_set_length_callback(_decoder, &FLACStream::callWrapLength);
::FLAC__seekable_stream_decoder_set_eof_callback(_decoder, &FLACStream::callWrapEOF);
::FLAC__seekable_stream_decoder_set_write_callback(_decoder, &FLACStream::callWrapWrite);
::FLAC__seekable_stream_decoder_set_metadata_callback(_decoder, &FLACStream::callWrapMetadata);
::FLAC__seekable_stream_decoder_set_error_callback(_decoder, &FLACStream::callWrapError);
::FLAC__seekable_stream_decoder_set_client_data(_decoder, (void *)this);
success = (::FLAC__seekable_stream_decoder_init(_decoder) == FLAC__SEEKABLE_STREAM_DECODER_OK);
#else
success = (::FLAC__stream_decoder_init_stream(
_decoder,
&FLACStream::callWrapRead,
&FLACStream::callWrapSeek,
&FLACStream::callWrapTell,
&FLACStream::callWrapLength,
&FLACStream::callWrapEOF,
&FLACStream::callWrapWrite,
&FLACStream::callWrapMetadata,
&FLACStream::callWrapError,
(void *)this
) == FLAC__STREAM_DECODER_INIT_STATUS_OK);
#endif
if (success) {
if (processUntilEndOfMetadata() && _streaminfo.channels > 0) {
_lastSample = _streaminfo.total_samples + 1;
_length = Timestamp(0, _lastSample - 1, getRate());
return; // no error occurred
}
}
warning("FLACStream: could not create audio stream");
}
FLACStream::~FLACStream() {
if (_decoder != nullptr) {
#ifdef LEGACY_FLAC
(void) ::FLAC__seekable_stream_decoder_finish(_decoder);
::FLAC__seekable_stream_decoder_delete(_decoder);
#else
(void) ::FLAC__stream_decoder_finish(_decoder);
::FLAC__stream_decoder_delete(_decoder);
#endif
}
if (_disposeAfterUse)
delete _inStream;
}
inline FLAC__StreamDecoderState FLACStream::getStreamDecoderState() const {
assert(_decoder != nullptr);
#ifdef LEGACY_FLAC
return ::FLAC__seekable_stream_decoder_get_stream_decoder_state(_decoder);
#else
return ::FLAC__stream_decoder_get_state(_decoder);
#endif
}
inline bool FLACStream::processSingleBlock() {
assert(_decoder != nullptr);
#ifdef LEGACY_FLAC
return 0 != ::FLAC__seekable_stream_decoder_process_single(_decoder);
#else
return 0 != ::FLAC__stream_decoder_process_single(_decoder);
#endif
}
inline bool FLACStream::processUntilEndOfMetadata() {
assert(_decoder != nullptr);
#ifdef LEGACY_FLAC
return 0 != ::FLAC__seekable_stream_decoder_process_until_end_of_metadata(_decoder);
#else
return 0 != ::FLAC__stream_decoder_process_until_end_of_metadata(_decoder);
#endif
}
bool FLACStream::seekAbsolute(FLAC__uint64 sample) {
assert(_decoder != nullptr);
#ifdef LEGACY_FLAC
const bool result = (0 != ::FLAC__seekable_stream_decoder_seek_absolute(_decoder, sample));
#else
const bool result = (0 != ::FLAC__stream_decoder_seek_absolute(_decoder, sample));
#endif
if (result) {
_lastSampleWritten = (_lastSample != 0 && sample >= _lastSample); // only set if we are SURE
}
return result;
}
bool FLACStream::seek(const Timestamp &where) {
_sampleCache.bufFill = 0;
_sampleCache.bufReadPos = nullptr;
// FLAC uses the sample pair number, thus we always use "false" for the isStereo parameter
// of the convertTimeToStreamPos helper.
return seekAbsolute((FLAC__uint64)convertTimeToStreamPos(where, getRate(), false).totalNumberOfFrames());
}
int FLACStream::readBuffer(int16 *buffer, const int numSamples) {
const uint numChannels = getChannels();
if (numChannels == 0) {
warning("FLACStream: Stream not successfully initialized, cant playback");
return -1; // streaminfo wasnt read!
}
assert(numSamples % numChannels == 0); // must be multiple of channels!
assert(buffer != nullptr);
assert(_outBuffer == nullptr);
assert(_requestedSamples == 0);
_outBuffer = buffer;
_requestedSamples = numSamples;
// If there is still data in our buffer from the last time around,
// copy that first.
if (_sampleCache.bufFill > 0) {
assert(_sampleCache.bufReadPos >= _sampleCache.bufData);
assert(_sampleCache.bufFill % numChannels == 0);
const uint copySamples = MIN((uint)numSamples, _sampleCache.bufFill);
memcpy(buffer, _sampleCache.bufReadPos, copySamples*sizeof(buffer[0]));
_outBuffer = buffer + copySamples;
_requestedSamples = numSamples - copySamples;
_sampleCache.bufReadPos += copySamples;
_sampleCache.bufFill -= copySamples;
}
bool decoderOk = true;
FLAC__StreamDecoderState state = getStreamDecoderState();
// Keep poking FLAC to process more samples until we completely satisfied the request
// respectively until we run out of data.
while (!_lastSampleWritten && _requestedSamples > 0 && state == FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC) {
assert(_sampleCache.bufFill == 0);
assert(_requestedSamples % numChannels == 0);
processSingleBlock();
state = getStreamDecoderState();
if (state == FLAC__STREAM_DECODER_END_OF_STREAM)
_lastSampleWritten = true;
}
// Error handling
switch (state) {
case FLAC__STREAM_DECODER_END_OF_STREAM:
_lastSampleWritten = true;
break;
case FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC:
break;
default:
decoderOk = false;
warning("FLACStream: An error occurred while decoding. DecoderState is: %d", getStreamDecoderState());
}
// Compute how many samples we actually produced
const int samples = (int)(_outBuffer - buffer);
assert(samples % numChannels == 0);
_outBuffer = nullptr; // basically unnecessary, only for the purpose of the asserts
_requestedSamples = 0; // basically unnecessary, only for the purpose of the asserts
return decoderOk ? samples : -1;
}
inline ::FLAC__SeekableStreamDecoderReadStatus FLACStream::callbackRead(FLAC__byte buffer[], FLAC_size_t *bytes) {
if (*bytes == 0) {
#ifdef LEGACY_FLAC
return FLAC__SEEKABLE_STREAM_DECODER_READ_STATUS_ERROR; /* abort to avoid a deadlock */
#else
return FLAC__STREAM_DECODER_READ_STATUS_ABORT; /* abort to avoid a deadlock */
#endif
}
const uint32 bytesRead = _inStream->read(buffer, *bytes);
if (bytesRead == 0) {
#ifdef LEGACY_FLAC
return _inStream->eos() ? FLAC__SEEKABLE_STREAM_DECODER_READ_STATUS_OK : FLAC__SEEKABLE_STREAM_DECODER_READ_STATUS_ERROR;
#else
return _inStream->eos() ? FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM : FLAC__STREAM_DECODER_READ_STATUS_ABORT;
#endif
}
*bytes = static_cast<uint>(bytesRead);
#ifdef LEGACY_FLAC
return FLAC__SEEKABLE_STREAM_DECODER_READ_STATUS_OK;
#else
return FLAC__STREAM_DECODER_READ_STATUS_CONTINUE;
#endif
}
void FLACStream::setBestConvertBufferMethod() {
PFCONVERTBUFFERS tempMethod = &FLACStream::convertBuffersGeneric;
const uint numChannels = getChannels();
const uint8 numBits = (uint8)_streaminfo.bits_per_sample;
assert(numChannels >= 1);
assert(numBits >= 4 && numBits <=32);
if (numChannels == 1) {
if (numBits == 8)
tempMethod = &FLACStream::convertBuffersMono8Bit;
if (numBits == BUFTYPE_BITS)
tempMethod = &FLACStream::convertBuffersMonoNS;
} else if (numChannels == 2) {
if (numBits == 8)
tempMethod = &FLACStream::convertBuffersStereo8Bit;
if (numBits == BUFTYPE_BITS)
tempMethod = &FLACStream::convertBuffersStereoNS;
} /* else ... */
_methodConvertBuffers = tempMethod;
}
// 1 channel, no scaling
void FLACStream::convertBuffersMonoNS(SampleType* bufDestination, const FLAC__int32 *inChannels[], uint numSamples, const uint numChannels, const uint8 numBits) {
assert(numChannels == 1);
assert(numBits == BUFTYPE_BITS);
FLAC__int32 const* inChannel1 = inChannels[0];
while (numSamples >= 4) {
bufDestination[0] = static_cast<SampleType>(inChannel1[0]);
bufDestination[1] = static_cast<SampleType>(inChannel1[1]);
bufDestination[2] = static_cast<SampleType>(inChannel1[2]);
bufDestination[3] = static_cast<SampleType>(inChannel1[3]);
bufDestination += 4;
inChannel1 += 4;
numSamples -= 4;
}
for (; numSamples > 0; --numSamples) {
*bufDestination++ = static_cast<SampleType>(*inChannel1++);
}
inChannels[0] = inChannel1;
assert(numSamples == 0); // dint copy too many samples
}
// 1 channel, scaling from 8Bit
void FLACStream::convertBuffersMono8Bit(SampleType* bufDestination, const FLAC__int32 *inChannels[], uint numSamples, const uint numChannels, const uint8 numBits) {
assert(numChannels == 1);
assert(numBits == 8);
assert(8 < BUFTYPE_BITS);
FLAC__int32 const* inChannel1 = inChannels[0];
while (numSamples >= 4) {
bufDestination[0] = static_cast<SampleType>(inChannel1[0]) << (BUFTYPE_BITS - 8);
bufDestination[1] = static_cast<SampleType>(inChannel1[1]) << (BUFTYPE_BITS - 8);
bufDestination[2] = static_cast<SampleType>(inChannel1[2]) << (BUFTYPE_BITS - 8);
bufDestination[3] = static_cast<SampleType>(inChannel1[3]) << (BUFTYPE_BITS - 8);
bufDestination += 4;
inChannel1 += 4;
numSamples -= 4;
}
for (; numSamples > 0; --numSamples) {
*bufDestination++ = static_cast<SampleType>(*inChannel1++) << (BUFTYPE_BITS - 8);
}
inChannels[0] = inChannel1;
assert(numSamples == 0); // dint copy too many samples
}
// 2 channels, no scaling
void FLACStream::convertBuffersStereoNS(SampleType* bufDestination, const FLAC__int32 *inChannels[], uint numSamples, const uint numChannels, const uint8 numBits) {
assert(numChannels == 2);
assert(numBits == BUFTYPE_BITS);
assert(numSamples % 2 == 0); // must be integral multiply of channels
FLAC__int32 const* inChannel1 = inChannels[0]; // Left Channel
FLAC__int32 const* inChannel2 = inChannels[1]; // Right Channel
while (numSamples >= 2*2) {
bufDestination[0] = static_cast<SampleType>(inChannel1[0]);
bufDestination[1] = static_cast<SampleType>(inChannel2[0]);
bufDestination[2] = static_cast<SampleType>(inChannel1[1]);
bufDestination[3] = static_cast<SampleType>(inChannel2[1]);
bufDestination += 2 * 2;
inChannel1 += 2;
inChannel2 += 2;
numSamples -= 2 * 2;
}
while (numSamples > 0) {
bufDestination[0] = static_cast<SampleType>(*inChannel1++);
bufDestination[1] = static_cast<SampleType>(*inChannel2++);
bufDestination += 2;
numSamples -= 2;
}
inChannels[0] = inChannel1;
inChannels[1] = inChannel2;
assert(numSamples == 0); // dint copy too many samples
}
// 2 channels, scaling from 8Bit
void FLACStream::convertBuffersStereo8Bit(SampleType* bufDestination, const FLAC__int32 *inChannels[], uint numSamples, const uint numChannels, const uint8 numBits) {
assert(numChannels == 2);
assert(numBits == 8);
assert(numSamples % 2 == 0); // must be integral multiply of channels
assert(8 < BUFTYPE_BITS);
FLAC__int32 const* inChannel1 = inChannels[0]; // Left Channel
FLAC__int32 const* inChannel2 = inChannels[1]; // Right Channel
while (numSamples >= 2*2) {
bufDestination[0] = static_cast<SampleType>(inChannel1[0]) << (BUFTYPE_BITS - 8);
bufDestination[1] = static_cast<SampleType>(inChannel2[0]) << (BUFTYPE_BITS - 8);
bufDestination[2] = static_cast<SampleType>(inChannel1[1]) << (BUFTYPE_BITS - 8);
bufDestination[3] = static_cast<SampleType>(inChannel2[1]) << (BUFTYPE_BITS - 8);
bufDestination += 2 * 2;
inChannel1 += 2;
inChannel2 += 2;
numSamples -= 2 * 2;
}
while (numSamples > 0) {
bufDestination[0] = static_cast<SampleType>(*inChannel1++) << (BUFTYPE_BITS - 8);
bufDestination[1] = static_cast<SampleType>(*inChannel2++) << (BUFTYPE_BITS - 8);
bufDestination += 2;
numSamples -= 2;
}
inChannels[0] = inChannel1;
inChannels[1] = inChannel2;
assert(numSamples == 0); // dint copy too many samples
}
// all Purpose-conversion - slowest of em all
void FLACStream::convertBuffersGeneric(SampleType* bufDestination, const FLAC__int32 *inChannels[], uint numSamples, const uint numChannels, const uint8 numBits) {
assert(numSamples % numChannels == 0); // must be integral multiply of channels
if (numBits < BUFTYPE_BITS) {
const uint8 kPower = (uint8)(BUFTYPE_BITS - numBits);
for (; numSamples > 0; numSamples -= numChannels) {
for (uint i = 0; i < numChannels; ++i)
*bufDestination++ = static_cast<SampleType>(*(inChannels[i]++)) << kPower;
}
} else if (numBits > BUFTYPE_BITS) {
const uint8 kPower = (uint8)(numBits - BUFTYPE_BITS);
for (; numSamples > 0; numSamples -= numChannels) {
for (uint i = 0; i < numChannels; ++i)
*bufDestination++ = static_cast<SampleType>(*(inChannels[i]++) >> kPower);
}
} else {
for (; numSamples > 0; numSamples -= numChannels) {
for (uint i = 0; i < numChannels; ++i)
*bufDestination++ = static_cast<SampleType>(*(inChannels[i]++));
}
}
assert(numSamples == 0); // dint copy too many samples
}
inline ::FLAC__StreamDecoderWriteStatus FLACStream::callbackWrite(const ::FLAC__Frame *frame, const FLAC__int32 * const buffer[]) {
assert(frame->header.channels == _streaminfo.channels);
assert(frame->header.sample_rate == _streaminfo.sample_rate);
assert(frame->header.bits_per_sample == _streaminfo.bits_per_sample);
assert(frame->header.number_type == FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER || _streaminfo.min_blocksize == _streaminfo.max_blocksize);
// We require that either the sample cache is empty, or that no samples were requested
assert(_sampleCache.bufFill == 0 || _requestedSamples == 0);
uint numSamples = frame->header.blocksize;
const uint numChannels = getChannels();
const uint8 numBits = (uint8)_streaminfo.bits_per_sample;
assert(_requestedSamples % numChannels == 0); // must be integral multiply of channels
const FLAC__uint64 firstSampleNumber = (frame->header.number_type == FLAC__FRAME_NUMBER_TYPE_SAMPLE_NUMBER) ?
frame->header.number.sample_number : (static_cast<FLAC__uint64>(frame->header.number.frame_number)) * _streaminfo.max_blocksize;
// Check whether we are about to reach beyond the last sample we are supposed to play.
if (_lastSample != 0 && firstSampleNumber + numSamples >= _lastSample) {
numSamples = (uint)(firstSampleNumber >= _lastSample ? 0 : _lastSample - firstSampleNumber);
_lastSampleWritten = true;
}
// The value in _requestedSamples counts raw samples, so if there are more than one
// channel, we have to multiply the number of available sample "pairs" by numChannels
numSamples *= numChannels;
const FLAC__int32 *inChannels[MAX_OUTPUT_CHANNELS];
for (uint i = 0; i < numChannels; ++i)
inChannels[i] = buffer[i];
// write the incoming samples directly into the buffer provided to us by the mixer
if (_requestedSamples > 0) {
assert(_requestedSamples % numChannels == 0);
assert(_outBuffer != nullptr);
// Copy & convert the available samples (limited both by how many we have available, and
// by how many are actually needed).
const uint copySamples = MIN(_requestedSamples, numSamples);
(*_methodConvertBuffers)(_outBuffer, inChannels, copySamples, numChannels, numBits);
_requestedSamples -= copySamples;
numSamples -= copySamples;
_outBuffer += copySamples;
}
// Write all remaining samples (i.e. those which didn't fit into the mixer buffer)
// into the sample cache.
if (_sampleCache.bufFill == 0)
_sampleCache.bufReadPos = _sampleCache.bufData;
const uint cacheSpace = (_sampleCache.bufData + BUFFER_SIZE) - (_sampleCache.bufReadPos + _sampleCache.bufFill);
assert(numSamples <= cacheSpace);
(*_methodConvertBuffers)(_sampleCache.bufReadPos + _sampleCache.bufFill, inChannels, numSamples, numChannels, numBits);
_sampleCache.bufFill += numSamples;
return FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE;
}
inline ::FLAC__SeekableStreamDecoderSeekStatus FLACStream::callbackSeek(FLAC__uint64 absoluteByteOffset) {
_inStream->seek(absoluteByteOffset, SEEK_SET);
const bool result = (absoluteByteOffset == (FLAC__uint64)_inStream->pos());
#ifdef LEGACY_FLAC
return result ? FLAC__SEEKABLE_STREAM_DECODER_SEEK_STATUS_OK : FLAC__SEEKABLE_STREAM_DECODER_SEEK_STATUS_ERROR;
#else
return result ? FLAC__STREAM_DECODER_SEEK_STATUS_OK : FLAC__STREAM_DECODER_SEEK_STATUS_ERROR;
#endif
}
inline ::FLAC__SeekableStreamDecoderTellStatus FLACStream::callbackTell(FLAC__uint64 *absoluteByteOffset) {
*absoluteByteOffset = static_cast<FLAC__uint64>(_inStream->pos());
#ifdef LEGACY_FLAC
return FLAC__SEEKABLE_STREAM_DECODER_TELL_STATUS_OK;
#else
return FLAC__STREAM_DECODER_TELL_STATUS_OK;
#endif
}
inline ::FLAC__SeekableStreamDecoderLengthStatus FLACStream::callbackLength(FLAC__uint64 *streamLength) {
*streamLength = static_cast<FLAC__uint64>(_inStream->size());
#ifdef LEGACY_FLAC
return FLAC__SEEKABLE_STREAM_DECODER_LENGTH_STATUS_OK;
#else
return FLAC__STREAM_DECODER_LENGTH_STATUS_OK;
#endif
}
inline bool FLACStream::callbackEOF() {
return _inStream->eos();
}
inline void FLACStream::callbackMetadata(const ::FLAC__StreamMetadata *metadata) {
assert(_decoder != nullptr);
assert(metadata->type == FLAC__METADATA_TYPE_STREAMINFO); // others arent really interesting
_streaminfo = metadata->data.stream_info;
setBestConvertBufferMethod(); // should be set after getting stream-information. FLAC always parses the info first
}
inline void FLACStream::callbackError(::FLAC__StreamDecoderErrorStatus status) {
// some of these are non-critical-Errors
debug(1, "FLACStream: An error occurred while decoding. DecoderStateError is: %d", status);
}
/* Static Callback Wrappers */
::FLAC__SeekableStreamDecoderReadStatus FLACStream::callWrapRead(const ::FLAC__SeekableStreamDecoder *decoder, FLAC__byte buffer[], FLAC_size_t *bytes, void *clientData) {
FLACStream *instance = (FLACStream *)clientData;
assert(nullptr != instance);
return instance->callbackRead(buffer, bytes);
}
::FLAC__SeekableStreamDecoderSeekStatus FLACStream::callWrapSeek(const ::FLAC__SeekableStreamDecoder *decoder, FLAC__uint64 absoluteByteOffset, void *clientData) {
FLACStream *instance = (FLACStream *)clientData;
assert(nullptr != instance);
return instance->callbackSeek(absoluteByteOffset);
}
::FLAC__SeekableStreamDecoderTellStatus FLACStream::callWrapTell(const ::FLAC__SeekableStreamDecoder *decoder, FLAC__uint64 *absoluteByteOffset, void *clientData) {
FLACStream *instance = (FLACStream *)clientData;
assert(nullptr != instance);
return instance->callbackTell(absoluteByteOffset);
}
::FLAC__SeekableStreamDecoderLengthStatus FLACStream::callWrapLength(const ::FLAC__SeekableStreamDecoder *decoder, FLAC__uint64 *streamLength, void *clientData) {
FLACStream *instance = (FLACStream *)clientData;
assert(nullptr != instance);
return instance->callbackLength(streamLength);
}
FLAC__bool FLACStream::callWrapEOF(const ::FLAC__SeekableStreamDecoder *decoder, void *clientData) {
FLACStream *instance = (FLACStream *)clientData;
assert(nullptr != instance);
return instance->callbackEOF();
}
::FLAC__StreamDecoderWriteStatus FLACStream::callWrapWrite(const ::FLAC__SeekableStreamDecoder *decoder, const ::FLAC__Frame *frame, const FLAC__int32 * const buffer[], void *clientData) {
FLACStream *instance = (FLACStream *)clientData;
assert(nullptr != instance);
return instance->callbackWrite(frame, buffer);
}
void FLACStream::callWrapMetadata(const ::FLAC__SeekableStreamDecoder *decoder, const ::FLAC__StreamMetadata *metadata, void *clientData) {
FLACStream *instance = (FLACStream *)clientData;
assert(nullptr != instance);
instance->callbackMetadata(metadata);
}
void FLACStream::callWrapError(const ::FLAC__SeekableStreamDecoder *decoder, ::FLAC__StreamDecoderErrorStatus status, void *clientData) {
FLACStream *instance = (FLACStream *)clientData;
assert(nullptr != instance);
instance->callbackError(status);
}
#pragma mark -
#pragma mark --- FLAC factory functions ---
#pragma mark -
SeekableAudioStream *makeFLACStream(
Common::SeekableReadStream *stream,
DisposeAfterUse::Flag disposeAfterUse) {
SeekableAudioStream *s = new FLACStream(stream, disposeAfterUse);
if (s && s->endOfData()) {
delete s;
return nullptr;
} else {
return s;
}
}
} // End of namespace Audio
#endif // #ifdef USE_FLAC