I'm trying to change the pitch of the audio but not able to save the effected audio . How to save effected audio in background?

Question

This method filter the audio and change the pitch but not saved anywhere where

-(void)Pitch:(NSNumber*)pitch
{
 audioPlayerNode = [AVAudioPlayerNode new];
[self.audioEngine attachNode:audioPlayerNode];

AVAudioUnitTimePitch *timePitchEffect = [AVAudioUnitTimePitch new];
[self.audioEngine attachNode:timePitchEffect];
    timePitchEffect.pitch = [pitch floatValue];

[self.audioEngine connect:audioPlayerNode
                       to:timePitchEffect
                   format:nil];
[self.audioEngine connect:timePitchEffect
                       to:self.audioEngine.outputNode
                   format:nil];

[audioPlayerNode scheduleFile:self.audioFile
                       atTime:nil
            completionHandler:nil];

[self.audioEngine startAndReturnError:&audioEngineError];
 }

Here i m able to create the audio file but no sound is available in the audio can any one help me to get out of this new file is created called outputfile but when i play that audio no sound is there just mute, complete audio is created but without sound

-(void)saveEffectedAudioToFolder

{
AVAudioUnitTimePitch *pitchEffect = [AVAudioUnitTimePitch new];

NSMutableDictionary *recordSetting = [[NSMutableDictionary alloc] init];

[recordSetting setValue :[NSNumber numberWithInt:kAudioFormatLinearPCM] forKey:AVFormatIDKey];
[recordSetting setValue:[NSNumber numberWithFloat:44100.0] forKey:AVSampleRateKey];
[recordSetting setValue:[NSNumber numberWithInt: 2] forKey:AVNumberOfChannelsKey];
[recordSetting setValue :[NSNumber numberWithInt:16] forKey:AVLinearPCMBitDepthKey];
[recordSetting setValue :[NSNumber numberWithBool:NO] forKey:AVLinearPCMIsBigEndianKey];
[recordSetting setValue :[NSNumber numberWithBool:NO] forKey:AVLinearPCMIsFloatKey];
[recordSetting setValue:[NSNumber numberWithFloat:pitch] forKey:AVAudioTimePitchAlgorithmSpectral];



AVAudioFormat *commonFormat = [[AVAudioFormat alloc] initWithSettings:recordSetting];
pitchEffect.pitch =pitch;

[self setupEQ];


NSError *error12;
[_audioEngine startAndReturnError:&error12];
if (!error12)
{
    NSLog(@"Engine = %@",_audioEngine);
    [audioPlayerNode scheduleFile:_audioFile atTime:nil completionHandler:nil];


    NSError *error;
    _outputFile = [[AVAudioFile alloc] initForWriting:[self testFilePathURL] settings:commonFormat.settings error:&error];
    NSLog(@"outputfile = %@",_outputFile);
    if (error)
    {
        NSLog(@"outputFile error = %@",error);
    }
    else

    {

        [SVProgressHUD dismiss];
        [audioPlayerNode installTapOnBus:0 bufferSize:8192  format:_audioFile.processingFormat block:^(AVAudioPCMBuffer *buffer, AVAudioTime *when) {
            NSLog(@"Buffer Size = %@",buffer);
            NSLog(@"when = %lld",when.sampleTime);
            NSLog(@"outputfile length = %lli",_outputFile.length);
            NSLog(@"input file length = %lld",_audioFile.length);
            if (_outputFile.length<=_audioFile.length)
            {
                NSError *error;

                [_outputFile writeFromBuffer:buffer error:&error];

                if (error)
                {
                    NSLog(@"writebuffererror =%@",error);
                }
            }
            else
            {
                NSError *error2;



                [audioPlayerNode removeTapOnBus:0];

                // player2 = [[AVAudioPlayer alloc] initWithContentsOfURL:[self testFilePathURL] error:&error2];
                //player2.delegate = self;

                NSLog(@"Pathththt = %@",[self testFilePathURL]);
                NSLog(@"error = %@",error2);
                [audioPlayerNode scheduleFile:_outputFile atTime:nil completionHandler:nil];


                [audioPlayerNode play];
                // [self toMp3];
            }

        }];
    }
}
else
{
    NSLog(@"error12 =%@",error12);
}

}





- (void)setupEQ
{
NSLog(@"setupEQ");

_unitEq = [[AVAudioUnitEQ alloc] initWithNumberOfBands:12];
_unitEq.globalGain = 3.0;
AVAudioUnitEQFilterParameters *filterParameters;
filterParameters = _unitEq.bands[0];
filterParameters.filterType = AVAudioUnitEQFilterTypeParametric;
filterParameters.frequency = pitch;
filterParameters.bandwidth = 1.0;
filterParameters.gain = 20.0f;
filterParameters.bypass = FALSE;

filterParameters = _unitEq.bands[1];
filterParameters.filterType = AVAudioUnitEQFilterTypeParametric;
filterParameters.frequency = pitch;
filterParameters.bandwidth = 1.0;
filterParameters.gain = 20.0f;
filterParameters.bypass = FALSE;

filterParameters = _unitEq.bands[2];
filterParameters.filterType = AVAudioUnitEQFilterTypeParametric;
filterParameters.frequency = pitch;
filterParameters.bandwidth = 1.0;
filterParameters.gain = 20.0f;
filterParameters.bypass = FALSE;

filterParameters = _unitEq.bands[3];
filterParameters.filterType = AVAudioUnitEQFilterTypeParametric;
filterParameters.frequency = pitch;
filterParameters.bandwidth = 1.0;
filterParameters.gain = 20.0f;
filterParameters.bypass = FALSE;

filterParameters = _unitEq.bands[4];
filterParameters.filterType = AVAudioUnitEQFilterTypeParametric;
filterParameters.frequency = pitch;
filterParameters.bandwidth = 1.0;
filterParameters.gain = 20.0f;
filterParameters.bypass = FALSE;

filterParameters = _unitEq.bands[5];
filterParameters.filterType = AVAudioUnitEQFilterTypeParametric;
filterParameters.frequency = pitch;
filterParameters.bandwidth = 1.0;
filterParameters.gain = 20.0f;
filterParameters.bypass = FALSE;

filterParameters = _unitEq.bands[6];
filterParameters.filterType = AVAudioUnitEQFilterTypeParametric;
filterParameters.frequency = pitch;
filterParameters.bandwidth = 1.0;
filterParameters.gain = 20.0f;
filterParameters.bypass = FALSE;

filterParameters = _unitEq.bands[7];
filterParameters.filterType = AVAudioUnitEQFilterTypeParametric;
filterParameters.frequency = pitch;
filterParameters.bandwidth = 1.0;
filterParameters.gain =20.0f;
filterParameters.bypass = FALSE;

filterParameters = _unitEq.bands[8];
filterParameters.filterType = AVAudioUnitEQFilterTypeParametric;
filterParameters.frequency = pitch;
filterParameters.bandwidth = 1.0;
filterParameters.gain = 20.0f;
filterParameters.bypass = FALSE;

filterParameters = _unitEq.bands[9];
filterParameters.filterType = AVAudioUnitEQFilterTypeParametric;
filterParameters.frequency = pitch;
filterParameters.bandwidth = 1.0;
filterParameters.gain =20.0f;
filterParameters.bypass = FALSE;


filterParameters = _unitEq.bands[10];
filterParameters.filterType = AVAudioUnitEQFilterTypeLowPass;
filterParameters.frequency = pitch;
filterParameters.bypass = FALSE;

filterParameters = _unitEq.bands[11];
filterParameters.filterType = AVAudioUnitEQFilterTypeHighPass;
filterParameters.frequency = pitch;
filterParameters.bypass = FALSE;
[_audioEngine attachNode:_unitEq];

}

Lakshmi Keerthana Siddu · Answer 1 · 2017-01-12T09:06:53.750

You should replace

[audioPlayerNode installTapOnBus:0 bufferSize:8192  format:_audioFile.processingFormat block:^(AVAudioPCMBuffer *buffer, AVAudioTime *when) {
            NSLog(@"Buffer Size = %@",buffer);
            NSLog(@"when = %lld",when.sampleTime);
            NSLog(@"outputfile length = %lli",_outputFile.length);
            NSLog(@"input file length = %lld",_audioFile.length);
            if (_outputFile.length<=_audioFile.length)
            {
                NSError *error;

                [_outputFile writeFromBuffer:buffer error:&error];

                if (error)
                {
                    NSLog(@"writebuffererror =%@",error);
                }
            }
            else
            {
                NSError *error2;



                [audioPlayerNode removeTapOnBus:0];

                // player2 = [[AVAudioPlayer alloc] initWithContentsOfURL:[self testFilePathURL] error:&error2];
                //player2.delegate = self;

                NSLog(@"Pathththt = %@",[self testFilePathURL]);
                NSLog(@"error = %@",error2);
                [audioPlayerNode scheduleFile:_outputFile atTime:nil completionHandler:nil];


                [audioPlayerNode play];
                // [self toMp3];
            }

        }];
    }

With

Here input means audioEngine.inputnode

AVAudioInputNode *input = [audioEngine inputNode]; 
AVAudioFormat *format = [input outputFormatForBus: 0];

outputFile = [[AVAudioFile alloc] initForWriting:[self testFilePathURL] settings:recordSetting error:&error];
    if (error)
    {
        //  NSLog(@"outputFile error = %@",error);
         
    }
    else
    {
        //        dispatch_async(dispatch_get_global_queue( DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^(void)
        //        {
        [input installTapOnBus:0 bufferSize:8091 format:format block:^(AVAudioPCMBuffer * _Nonnull buffer, AVAudioTime * _Nonnull when) {
            
            
            if (outputFile.length<audioFile.length)
            {
                
                NSError *error;
                [outputFile writeFromBuffer:buffer error:&error];
                if (error)
                {
                    NSLog(@"writebuffererror =%@",error);
                    

                }
            }
            else
            {
                
                activityMainView.hidden=YES;
                
                [input removeTapOnBus:0];
                
                //  [self savingAudioFile];
                
                
                //_doneButtonImageView.image=[UIImage imageNamed:@"save"];
                [self doneButtonClick:nil];
                NSError *error2;
                NSLog(@"Pathththt = %@",[self testFilePathURL]);
                NSLog(@"error = %@",error2);
                
               
                
            }
            
            
            
        }];
        
        
         
        //     });
        
        
    }

i tried this its not working... audio is created but no voice...silent audio is created... — Mitesh Varu, Jan 09 '17 at 05:27
AVAudioInputNode *input = [audioEngine inputNode]; AVAudioFormat *format = [input outputFormatForBus: 0]; can you write these lines of code before writing outputfile. It's working for me. — Lakshmi Keerthana Siddu, Jan 09 '17 at 05:35

I'm trying to change the pitch of the audio but not able to save the effected audio . How to save effected audio in background?

1 Answers1