音频录制之AVAudioRecorder

#import <UIKit/UIKit.h>
#import <AVFoundation/AVFoundation.h>

@interface AudioPlayerViewController : UIViewController{
AVAudioPlayer *audioPlayer;
AVAudioRecorder *audioRecorder;
int recordEncoding;
enum
{
    ENC_AAC = 1,
    ENC_ALAC = 2,
    ENC_IMA4 = 3,
    ENC_ILBC = 4,
    ENC_ULAW = 5,
    ENC_PCM = 6,
} encodingTypes;
}

- (IBAction) startRecording;
- (IBAction) stopRecording;
- (IBAction) playRecording;
- (IBAction) stopPlaying;

- (IBAction)btnclick:(id)sender;
@end

// M文件

#import "AudioPlayerViewController.h"

@implementation AudioPlayerViewController

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) {
// Custom initialization
    }
return self;
}

- (void)viewDidLoad
{
    [super viewDidLoad];
// Do any additional setup after loading the view from its nib.
    recordEncoding = ENC_AAC;
}

- (void)dealloc
{
    [audioPlayer release];
    [audioRecorder release];
    [super dealloc];
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}

-(IBAction) startRecording
{
    NSLog(@"startRecording");
    [audioRecorder release];
    audioRecorder = nil;

// Init audio with record capability
    AVAudioSession *audioSession = [AVAudioSession sharedInstance];
    [audioSession setCategory:AVAudioSessionCategoryRecord error:nil];

    NSMutableDictionary *recordSettings = [[NSMutableDictionary alloc] initWithCapacity:10];
if(recordEncoding == ENC_PCM)
    {
        [recordSettings setObject:[NSNumber numberWithInt: kAudioFormatLinearPCM] forKey: AVFormatIDKey];
        [recordSettings setObject:[NSNumber numberWithFloat:44100.0] forKey: AVSampleRateKey];
        [recordSettings setObject:[NSNumber numberWithInt:2] forKey:AVNumberOfChannelsKey];
        [recordSettings setObject:[NSNumber numberWithInt:16] forKey:AVLinearPCMBitDepthKey];
        [recordSettings setObject:[NSNumber numberWithBool:NO] forKey:AVLinearPCMIsBigEndianKey];
        [recordSettings setObject:[NSNumber numberWithBool:NO] forKey:AVLinearPCMIsFloatKey];
    }
else
    {
        NSNumber *formatObject;

switch (recordEncoding) {
case (ENC_AAC):
                formatObject = [NSNumber numberWithInt: kAudioFormatMPEG4AAC];
break;
case (ENC_ALAC):
                formatObject = [NSNumber numberWithInt: kAudioFormatAppleLossless];
break;
case (ENC_IMA4):
                formatObject = [NSNumber numberWithInt: kAudioFormatAppleIMA4];
break;
case (ENC_ILBC):
                formatObject = [NSNumber numberWithInt: kAudioFormatiLBC];
break;
case (ENC_ULAW):
                formatObject = [NSNumber numberWithInt: kAudioFormatULaw];
break;
default:
                formatObject = [NSNumber numberWithInt: kAudioFormatAppleIMA4];
        }

        [recordSettings setObject:formatObject forKey: AVFormatIDKey];//ID
        [recordSettings setObject:[NSNumber numberWithFloat:44100.0] forKey: AVSampleRateKey];//采样率
        [recordSettings setObject:[NSNumber numberWithInt:2] forKey:AVNumberOfChannelsKey];//通道的数目,1单声道,2立体声
        [recordSettings setObject:[NSNumber numberWithInt:12800] forKey:AVEncoderBitRateKey];//解码率
        [recordSettings setObject:[NSNumber numberWithInt:16] forKey:AVLinearPCMBitDepthKey];//采样位
        [recordSettings setObject:[NSNumber numberWithInt: AVAudioQualityHigh] forKey: AVEncoderAudioQualityKey];
    }

    NSURL *url = [NSURL fileURLWithPath:[NSString stringWithFormat:@"%@/recordTest.caf", [[NSBundle mainBundle] resourcePath]]];


    NSError *error = nil;
    audioRecorder = [[ AVAudioRecorder alloc] initWithURL:url settings:recordSettings error:&error];

if ([audioRecorder prepareToRecord] == YES){
        [audioRecorder record];
    }else {
int errorCode = CFSwapInt32HostToBig ([error code]);
        NSLog(@"Error: %@ [%4.4s])" , [error localizedDescription], (char*)&errorCode);

    }
    NSLog(@"recording");
}

-(IBAction) stopRecording
{
    NSLog(@"stopRecording");
    [audioRecorder stop];
    NSLog(@"stopped");
}

-(IBAction) playRecording
{
    NSLog(@"playRecording");
// Init audio with playback capability
    AVAudioSession *audioSession = [AVAudioSession sharedInstance];
    [audioSession setCategory:AVAudioSessionCategoryPlayback error:nil];

    NSURL *url = [NSURL fileURLWithPath:[NSString stringWithFormat:@"%@/recordTest.caf", [[NSBundle mainBundle] resourcePath]]];
    NSError *error;
    audioPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL:url error:&error];
    audioPlayer.numberOfLoops = 0;
    [audioPlayer play];
    NSLog(@"playing");
}

-(IBAction) stopPlaying
{
    NSLog(@"stopPlaying");
    [audioPlayer stop];
    NSLog(@"stopped");
}

@end