Reduce Noise While Recording users Voice in iphone Application? - iphone

Question

I am trying to record users voice with background music playing behind. I am able to set a session and play background and record concurrently using AVAudioSessionCategoryPlayAndRecord. But it's recording lot's of noice,
Does any one have an idea how to reduce the noise?

Answer 1

#define DOCUMENTS [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0]
#define PATH_ARQUIVO [DOCUMENTS stringByAppendingPathComponent:#"gravacao.ma4"]
-(IBAction) recordAudio:(UIButton *)sender {
NSURL* urlArquivo = [[NSURL alloc] initFileURLWithPath:PATH_ARQUIVO];
NSDictionary *dic = [[NSDictionary alloc] initWithObjectsAndKeys:
[NSNumber numberWithInt:AVAudioQualityMin], AVEncoderAudioQualityKey,
[NSNumber numberWithInt:16], AVEncoderBitRateKey,
[NSNumber numberWithInt:2], AVNumberOfChannelsKey,
[NSNumber numberWithFloat:44.1], AVSampleRateKey,
nil];
NSError* error;
self.audioRecorder = [[AVAudioRecorder alloc] initWithURL:urlArquivo settings:dic error:&error];
if (error) {
NSLog(#"error: %#", [erro localizedDescription]);
} else {
//buffering
[self.audioRecorder prepareToRecord];
//recording
[self.audioRecorder record];
}
}
-(IBAction) stopRecorder:(UIButton *)sender {
if ([self.audioRecorder isRecording]) {
[self.audioRecorder stop];
}
}
-(IBAction) PlayAudio:(UIButton *)sender {
NSURL* urlArquivo = [[NSURL alloc] initFileURLWithPath:PATH_ARQUIVO];
NSError* error;
self.audioPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL:urlArquivo error:&error];
if (erro) {
NSLog(#"error %#", [error localizedDescription]);
} else {
self.audioPlayer.numberOfLoops = HUGE_VALF;
self.audioPlayer.enableRate = YES;
[self.audioPlayer prepareToPlay];
[self.audioPlayer play];
}
}
-(IBAction) stopPlaying:(UIButton *)sender {
if ([self.audioPlayer isPlaying]) {
[self.audioPlayer stop];
}
}
-(IBAction) changeRate:(UISlider *)sender {
self.audioPlayer.rate = sender.value * 2;
/* it's a UISlider, max value = 1, min = 0 */
}