cog/SoundFile/ShnFile.m

116 lines
2.0 KiB
Objective-C

//
// ShnFile.m
// Cog
//
// Created by Zaphod Beeblebrox on 6/6/05.
// Copyright 2005 __MyCompanyName__. All rights reserved.
//
#import "ShnFile.h"
@implementation ShnFile
- (BOOL)open:(const char *)filename
{
BOOL r;
r = [self readInfo:filename];
if (!r)
return NO;
bufferSize = shn_get_buffer_block_size(handle, 512);
buffer = malloc(bufferSize);
return YES;
}
- (BOOL)readInfo:(const char *)filename
{
shn_config conf;
int r;
conf.error_output_method = ERROR_OUTPUT_DEVNULL;
conf.seek_tables_path = NULL;
conf.relative_seek_tables_path = ".";
conf.verbose = 0;
conf.swap_bytes = 0;
handle = shn_load((char *)filename, conf);
if (!handle)
return NO;
r = shn_init_decoder(handle);
if (r < 0)
return NO;
channels = shn_get_channels(handle);
frequency = shn_get_samplerate(handle);
bitsPerSample = shn_get_bitspersample(handle);
unsigned int length;
length = shn_get_song_length(handle);
totalSize = (((double)(length)*frequency)/1000.0) * channels * (bitsPerSample/8);
bitRate = (int)((double)totalSize/((double)length/1000.0));
DBLog(@"Bitrate; %i", bitRate);
return YES;
}
- (int)fillBuffer:(void *)buf ofSize:(UInt32)size
{
int numread = bufferAmount;
int count = 0;
//Fill from buffer, going by bufferAmount
//if still needs more, decode and repeat
if (bufferAmount == 0)
{
bufferAmount = shn_read(handle, buffer, bufferSize);
if (bufferAmount == 0)
return 0;
}
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;
}
- (double)seekToTime:(double)milliseconds
{
unsigned int sec;
if (!shn_seekable(handle))
return -1.0;
sec = (int)(milliseconds/1000.0);
shn_seek(handle, sec);
return (sec * 1000.0);
}
- (void)close
{
if (shn_cleanup_decoder(handle))
shn_unload(handle);
}
@end