cog/Plugins/Flac/FlacDecoder.m

338 lines
8.8 KiB
Objective-C

//
// FlacDecoder.m
// zyVorbis
//
// Created by Vincent Spader on 1/25/05.
// Copyright 2005 Vincent Spader All rights reserved.
//
#import "FlacDecoder.h"
#import "Logging.h"
@implementation FlacDecoder
FLAC__StreamDecoderReadStatus ReadCallback(const FLAC__StreamDecoder *decoder, FLAC__byte blockBuffer[], size_t *bytes, void *client_data)
{
FlacDecoder *flacDecoder = (FlacDecoder *)client_data;
long bytesRead = [[flacDecoder source] read:blockBuffer amount:*bytes];
if(bytesRead < 0) {
*bytes = 0;
return FLAC__STREAM_DECODER_READ_STATUS_ABORT;
}
else if(bytesRead == 0) {
*bytes = 0;
[flacDecoder setEndOfStream:YES];
return FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM;
}
else {
*bytes = bytesRead;
return FLAC__STREAM_DECODER_READ_STATUS_CONTINUE;
}
}
FLAC__StreamDecoderSeekStatus SeekCallback(const FLAC__StreamDecoder *decoder, FLAC__uint64 absolute_byte_offset, void *client_data)
{
FlacDecoder *flacDecoder = (FlacDecoder *)client_data;
if(![[flacDecoder source] seek:absolute_byte_offset whence:SEEK_SET])
return FLAC__STREAM_DECODER_SEEK_STATUS_ERROR;
else
return FLAC__STREAM_DECODER_SEEK_STATUS_OK;
}
FLAC__StreamDecoderTellStatus TellCallback(const FLAC__StreamDecoder *decoder, FLAC__uint64 *absolute_byte_offset, void *client_data)
{
FlacDecoder *flacDecoder = (FlacDecoder *)client_data;
off_t pos;
if((pos = [[flacDecoder source] tell]) < 0)
return FLAC__STREAM_DECODER_TELL_STATUS_ERROR;
else {
*absolute_byte_offset = (FLAC__uint64)pos;
return FLAC__STREAM_DECODER_TELL_STATUS_OK;
}
}
FLAC__bool EOFCallback(const FLAC__StreamDecoder *decoder, void *client_data)
{
FlacDecoder *flacDecoder = (FlacDecoder *)client_data;
return (FLAC__bool)[flacDecoder endOfStream];
}
FLAC__StreamDecoderLengthStatus LengthCallback(const FLAC__StreamDecoder *decoder, FLAC__uint64 *stream_length, void *client_data)
{
FlacDecoder *flacDecoder = (FlacDecoder *)client_data;
if ([[flacDecoder source] seekable]) {
long currentPos = [[flacDecoder source] tell];
[[flacDecoder source] seek:0 whence:SEEK_END];
*stream_length = [[flacDecoder source] tell];
[[flacDecoder source] seek:currentPos whence:SEEK_SET];
return FLAC__STREAM_DECODER_LENGTH_STATUS_OK;
}
else {
*stream_length = 0;
return FLAC__STREAM_DECODER_LENGTH_STATUS_ERROR;
}
}
FLAC__StreamDecoderWriteStatus WriteCallback(const FLAC__StreamDecoder *decoder, const FLAC__Frame *frame, const FLAC__int32 * const sampleblockBuffer[], void *client_data)
{
FlacDecoder *flacDecoder = (FlacDecoder *)client_data;
void *blockBuffer = [flacDecoder blockBuffer];
int8_t *alias8;
int16_t *alias16;
int32_t *alias32;
int sample, channel;
int32_t audioSample;
switch(frame->header.bits_per_sample) {
case 8:
// Interleave the audio (no need for byte swapping)
alias8 = blockBuffer;
for(sample = 0; sample < frame->header.blocksize; ++sample) {
for(channel = 0; channel < frame->header.channels; ++channel) {
*alias8++ = (int8_t)sampleblockBuffer[channel][sample];
}
}
break;
case 16:
// Interleave the audio, converting to big endian byte order
alias16 = blockBuffer;
for(sample = 0; sample < frame->header.blocksize; ++sample) {
for(channel = 0; channel < frame->header.channels; ++channel) {
*alias16++ = (int16_t)OSSwapHostToBigInt16((int16_t)sampleblockBuffer[channel][sample]);
}
}
break;
case 24:
// Interleave the audio (no need for byte swapping)
alias8 = blockBuffer;
for(sample = 0; sample < frame->header.blocksize; ++sample) {
for(channel = 0; channel < frame->header.channels; ++channel) {
audioSample = sampleblockBuffer[channel][sample];
*alias8++ = (int8_t)(audioSample >> 16);
*alias8++ = (int8_t)(audioSample >> 8);
*alias8++ = (int8_t)audioSample;
}
}
break;
case 32:
// Interleave the audio, converting to big endian byte order
alias32 = blockBuffer;
for(sample = 0; sample < frame->header.blocksize; ++sample) {
for(channel = 0; channel < frame->header.channels; ++channel) {
*alias32++ = OSSwapHostToBigInt32(sampleblockBuffer[channel][sample]);
}
}
default:
ALog(@"Error, unsupported sample size.");
}
[flacDecoder setBlockBufferFrames:frame->header.blocksize];
return FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE;
}
// This callback is only called for STREAMINFO blocks
void MetadataCallback(const FLAC__StreamDecoder *decoder, const FLAC__StreamMetadata *metadata, void *client_data)
{
// Some flacs observed in the wild have multiple STREAMINFO metadata blocks,
// of which only first one has sane values, so only use values from the first STREAMINFO
// to determine stream format (this seems to be consistent with flac spec: http://flac.sourceforge.net/format.html)
FlacDecoder *flacDecoder = (FlacDecoder *)client_data;
if (!flacDecoder->hasStreamInfo) {
flacDecoder->channels = metadata->data.stream_info.channels;
flacDecoder->frequency = metadata->data.stream_info.sample_rate;
flacDecoder->bitsPerSample = metadata->data.stream_info.bits_per_sample;
flacDecoder->totalFrames = metadata->data.stream_info.total_samples;
[flacDecoder willChangeValueForKey:@"properties"];
[flacDecoder didChangeValueForKey:@"properties"];
flacDecoder->hasStreamInfo = YES;
}
}
void ErrorCallback(const FLAC__StreamDecoder *decoder, FLAC__StreamDecoderErrorStatus status, void *client_data)
{
//Do nothing?
}
- (BOOL)open:(id<CogSource>)s
{
[self setSource:s];
decoder = FLAC__stream_decoder_new();
if (decoder == NULL)
return NO;
if (FLAC__stream_decoder_init_stream(decoder,
ReadCallback,
([source seekable] ? SeekCallback : NULL),
([source seekable] ? TellCallback : NULL),
([source seekable] ? LengthCallback : NULL),
([source seekable] ? EOFCallback : NULL),
WriteCallback,
MetadataCallback,
ErrorCallback,
self
) != FLAC__STREAM_DECODER_INIT_STATUS_OK)
{
return NO;
}
FLAC__stream_decoder_process_until_end_of_metadata(decoder);
blockBuffer = malloc(SAMPLE_blockBuffer_SIZE);
return YES;
}
- (int)readAudio:(void *)buffer frames:(UInt32)frames
{
int framesRead = 0;
int bytesPerFrame = (bitsPerSample/8) * channels;
while (framesRead < frames)
{
if (blockBufferFrames == 0)
{
if (FLAC__stream_decoder_get_state (decoder) == FLAC__STREAM_DECODER_END_OF_STREAM)
{
break;
}
FLAC__stream_decoder_process_single(decoder);
}
int framesToRead = blockBufferFrames;
if (blockBufferFrames > frames)
{
framesToRead = frames;
}
memcpy(((uint8_t *)buffer) + (framesRead * bytesPerFrame), (uint8_t *)blockBuffer, framesToRead * bytesPerFrame);
frames -= framesToRead;
framesRead += framesToRead;
blockBufferFrames -= framesToRead;
if (blockBufferFrames > 0)
{
memmove((uint8_t *)blockBuffer, ((uint8_t *)blockBuffer) + (framesToRead * bytesPerFrame), blockBufferFrames * bytesPerFrame);
}
}
return framesRead;
}
- (void)close
{
if (decoder)
{
FLAC__stream_decoder_finish(decoder);
FLAC__stream_decoder_delete(decoder);
}
if (blockBuffer)
{
free(blockBuffer);
}
[source close];
[self setSource:nil];
decoder = NULL;
blockBuffer = NULL;
}
- (long)seek:(long)sample
{
FLAC__stream_decoder_seek_absolute(decoder, sample);
return sample;
}
//bs methods
- (char *)blockBuffer
{
return blockBuffer;
}
- (int)blockBufferFrames
{
return blockBufferFrames;
}
- (void)setBlockBufferFrames:(int)frames
{
blockBufferFrames = frames;
}
- (FLAC__StreamDecoder *)decoder
{
return decoder;
}
- (void)setSource:(id<CogSource>)s
{
[s retain];
[source release];
source = s;
}
- (id<CogSource>)source
{
return source;
}
- (void)setEndOfStream:(BOOL)eos
{
endOfStream = eos;
}
- (BOOL)endOfStream
{
return endOfStream;
}
- (NSDictionary *)properties
{
return [NSDictionary dictionaryWithObjectsAndKeys:
[NSNumber numberWithInt:channels],@"channels",
[NSNumber numberWithInt:bitsPerSample],@"bitsPerSample",
[NSNumber numberWithFloat:frequency],@"sampleRate",
[NSNumber numberWithDouble:totalFrames],@"totalFrames",
[NSNumber numberWithBool:[source seekable]], @"seekable",
@"big",@"endian",
nil];
}
+ (NSArray *)fileTypes
{
return [NSArray arrayWithObjects:@"flac", nil];
}
+ (NSArray *)mimeTypes
{
return [NSArray arrayWithObjects:@"audio/x-flac", nil];
}
+ (float)priority
{
return 1.0;
}
@end