cog/Audio/Decoders/FlacFile.m

//
//  FlacFile.m
//  zyVorbis
//
//  Created by Vincent Spader on 1/25/05.
//  Copyright 2005 Vincent Spader All rights reserved.
//

#import "FlacFile.h"


@implementation FlacFile

FLAC__StreamDecoderWriteStatus WriteProc(const FLAC__FileDecoder *decoder, const FLAC__Frame *frame, const FLAC__int32 * const sampleBuffer[], void *client_data)
{
//	DBLog(@"Write callback");
	FlacFile *flacFile = (FlacFile *)client_data;
	unsigned wide_samples = frame->header.blocksize;
	unsigned channels = frame->header.channels;
	
	UInt16 *buffer = (UInt16 *)[flacFile buffer];
	int i, j, c;

	for (i = j = 0; i < wide_samples; i++)
	{
		for (c = 0; c < channels; c++, j++)
		{
//			buffer[j] = CFSwapInt16LittleToHost(sampleBuffer[c][i]);
			buffer[j] = sampleBuffer[c][i];
		}
	}
	
//	memcpy([flacFile buffer], sampleBuffer, wide_samples*[flacFile bitsPerSample]/8);
	[flacFile setBufferAmount:(wide_samples * channels*2)];

	return FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE;
}

void MetadataProc(const FLAC__FileDecoder *decoder, const FLAC__StreamMetadata *metadata, void *client_data)
{
	FlacFile *flacFile = (FlacFile *)client_data;

	flacFile->channels = metadata->data.stream_info.channels;
	flacFile->frequency = metadata->data.stream_info.sample_rate;
	flacFile->bitsPerSample = metadata->data.stream_info.bits_per_sample;
	
//	DBLog(@"METADATAAAA LENGTH: %i %i %f", (int)(metadata->data.stream_info.total_samples),[flacFile frequency], (float)(metadata->data.stream_info.total_samples)/[flacFile frequency]);
	flacFile->totalSize = metadata->data.stream_info.total_samples*metadata->data.stream_info.channels*metadata->data.stream_info.bits_per_sample/8;
}

void ErrorProc(const FLAC__FileDecoder *decoder, FLAC__StreamDecoderErrorStatus status, void *client_data)
{
	DBLog(@"Error callback");
}

- (BOOL)open:(const char *)filename
{
	FLAC__bool status;
	
	decoder = FLAC__file_decoder_new();
	if (decoder == NULL)
		return NO;
		
	status = FLAC__file_decoder_set_filename(decoder, filename);
	if (status == false)
		return NO;
	
	status = FLAC__file_decoder_set_write_callback(decoder, WriteProc);
	if (status == false)
		return NO;

	status = FLAC__file_decoder_set_metadata_callback(decoder, MetadataProc);
	if (status == false)
		return NO;

	status = FLAC__file_decoder_set_error_callback(decoder, ErrorProc);
	if (status == false)
		return NO;
	
	status = FLAC__file_decoder_set_client_data(decoder, self);
	if (status == false)
		return NO;

	if (FLAC__file_decoder_init(decoder) != FLAC__FILE_DECODER_OK)
		return NO;

	FLAC__file_decoder_process_until_end_of_metadata(decoder);

	isBigEndian = hostIsBigEndian();
	
	return YES;
}

- (BOOL)readInfo:(const char *)filename
{
	FLAC__StreamMetadata streamInfo;
	
	FLAC__metadata_get_streaminfo(filename, &streamInfo);
	
	channels = streamInfo.data.stream_info.channels;
	frequency = streamInfo.data.stream_info.sample_rate;
	bitsPerSample = streamInfo.data.stream_info.bits_per_sample;
	
	totalSize = streamInfo.data.stream_info.total_samples*channels*(bitsPerSample/8);
	bitrate = 0;
	
	return YES;
}

- (int)fillBuffer:(void *)buf ofSize:(UInt32)size
{
	int count;
	int numread;
	
	if (bufferAmount == 0)
	{
		int i;
		if (FLAC__file_decoder_get_state (decoder) == FLAC__FILE_DECODER_END_OF_FILE)
		{
			return 0;
		}
		
		i = FLAC__file_decoder_process_single(decoder);// != FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE);
			//return 0;
//		[self writeSamplesToBuffer:buffer  fromBuffer:sampleBuffer ofSize:(status*2)];
//			write callback sets bufferAmount...frickin weird, also sets sampleBuffer
//		bufferAmount = status*4;
	}

	count = bufferAmount;
	if (bufferAmount > size)
	{
		count = size;
	}
	memcpy(buf, buffer, count);
	
	bufferAmount -= count;
	
	if (bufferAmount > 0)
		memmove(buffer, &buffer[count], bufferAmount);
	
	if (count < size)
		numread = [self fillBuffer:(&((char *)buf)[count]) ofSize:(size - count)];
	else
		numread = 0;
	
	return count + numread;
	
}

- (void)close
{
	if (decoder)
	{
		FLAC__file_decoder_finish(decoder);
		FLAC__file_decoder_delete(decoder);
	}
	decoder = NULL;
	
}

- (double)seekToTime:(double)milliseconds
{
	FLAC__file_decoder_seek_absolute(decoder, frequency * ((double)milliseconds/1000.0));
	
	return milliseconds;
}

//bs methods
- (char *)buffer
{
	return buffer;
}
- (int)bufferAmount
{
	return bufferAmount;
}
- (void)setBufferAmount:(int)amount
{
	bufferAmount = amount;
}

- (FLAC__FileDecoder *)decoder
{
	return decoder;
}

@end