Merging to WAV files in iOS

gistfile1.m

NSURL *originalFileName = [NSURL alloc];    

NSURL *RecordingPath =[NSURL fileURLWithPath:[appDelegate.RecordingPath stringByAppendingPathComponent: 
                                              [NSString stringWithFormat:@"RecordingFile.wav"]]];  
NSLog(@"LocalRecoding Path :%@",RecordingPath);


originalFileName=RecordingPath;

NSURL *temporaryFileName = [NSURL alloc];
temporaryFileName = [NSURL fileURLWithPath:[appDelegate.RecordingPath  stringByAppendingPathComponent: 
                                            [NSString stringWithFormat: @"tempRecordingFile.%@", @"wav"]]];

long totalAudioLen = 0;
long totalDataLen = 0;
long longSampleRate = 11025.0;
int channels = 2;
long byteRate = 16 * 11025.0 * channels/8;    

NSData * wav1Data = [NSData dataWithContentsOfFile:[originalFileName path]];
NSData * wav2Data = [NSData dataWithContentsOfFile:[temporaryFileName path]];

if([wav1Data length]>0 && [wav2Data length] >0)
{
int wav1DataSize = [wav1Data length] - 44;  
NSLog(@"WAV I:%d",wav1DataSize);
int wav2DataSize = [wav2Data length] - 44;
NSLog(@"WAV II:%d",wav2DataSize);
NSData *Wave1= [NSMutableData dataWithData:[wav1Data subdataWithRange:NSMakeRange(44, wav1DataSize)]];
NSData *Wave2 =[NSMutableData dataWithData:[wav2Data subdataWithRange:NSMakeRange(44, wav2DataSize)]];

NSLog(@"WAV 1:%d",[Wave1 length]);

NSLog(@"WAV 2:%d",[Wave2 length]);


totalAudioLen=[Wave1 length]+[Wave2 length];

totalDataLen = totalAudioLen + 44;  

Byte *header = (Byte*)malloc(44);
header[0] = 'R';  // RIFF/WAVE header
header[1] = 'I';
header[2] = 'F';
header[3] = 'F';
header[4] = (Byte) (totalDataLen & 0xff);
header[5] = (Byte) ((totalDataLen >> 8) & 0xff);
header[6] = (Byte) ((totalDataLen >> 16) & 0xff);
header[7] = (Byte) ((totalDataLen >> 24) & 0xff);
header[8] = 'W';
header[9] = 'A';
header[10] = 'V';
header[11] = 'E';
header[12] = 'f';  // 'fmt ' chunk
header[13] = 'm';
header[14] = 't';
header[15] = ' ';
header[16] = 16;  // 4 bytes: size of 'fmt ' chunk
header[17] = 0;
header[18] = 0;
header[19] = 0;
header[20] = 1;  // format = 1
header[21] = 0;
header[22] = (Byte) channels;
header[23] = 0;
header[24] = (Byte) (longSampleRate & 0xff);
header[25] = (Byte) ((longSampleRate >> 8) & 0xff);
header[26] = (Byte) ((longSampleRate >> 16) & 0xff);
header[27] = (Byte) ((longSampleRate >> 24) & 0xff);
header[28] = (Byte) (byteRate & 0xff);
header[29] = (Byte) ((byteRate >> 8) & 0xff);
header[30] = (Byte) ((byteRate >> 16) & 0xff);
header[31] = (Byte) ((byteRate >> 24) & 0xff);
header[32] = (Byte) (2 * 8 / 8);  // block align
header[33] = 0;
header[34] = 16;  // bits per sample
header[35] = 0;
header[36] = 'd';
header[37] = 'a';
header[38] = 't';
header[39] = 'a';
header[40] = (Byte) (totalAudioLen & 0xff);
header[41] = (Byte) ((totalAudioLen >> 8) & 0xff);
header[42] = (Byte) ((totalAudioLen >> 16) & 0xff);
header[43] = (Byte) ((totalAudioLen >> 24) & 0xff);


NSData *headerData = [NSData dataWithBytes:header length:44];

//Merge the sound data of the original file with the temp file and create a new sound file with the 
//update header.
NSMutableData * soundFileData = [NSMutableData alloc];
[soundFileData appendData:[headerData subdataWithRange:NSMakeRange(0, 44)]];
[soundFileData appendData:Wave1];
[soundFileData appendData:Wave2];

//delete the original file
NSFileManager * fm = [NSFileManager defaultManager];
[fm removeItemAtPath:[originalFileName path] error:nil]; 

//create a new file with merged audio with the original file name.
NSURL *mergedFilePath = [NSURL alloc];

mergedFilePath = [NSURL fileURLWithPath:[appDelegate.RecordingPath  stringByAppendingPathComponent: 
                                         [NSString stringWithFormat:[originalFileName lastPathComponent]]]];   

[[NSFileManager defaultManager] createFileAtPath:[mergedFilePath path] contents:soundFileData attributes:nil];  

NSLog(@"COMBINED FILE PATH :%@",mergedFilePath);
}