IOS-录音

//
//  ViewController.m
//  IOS_0322_录音
//
//  Created by ma c on 16/3/22.
//  Copyright © 2016年 博文科技. All rights reserved.
//

#import "ViewController.h"
#import <AVFoundation/AVFoundation.h>

@interface ViewController ()

@property (nonatomic, strong) AVAudioRecorder *recorder;
@property (nonatomic, strong) CADisplayLink *timer;
@property (nonatomic, assign) CGFloat silentDuration;


- (IBAction)startRecord;
- (IBAction)stopRecord;

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
}

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

- (void)addTimer
{
    self.timer = [CADisplayLink displayLinkWithTarget:self selector:@selector(update)];
    [self.timer addToRunLoop:[NSRunLoop mainRunLoop] forMode:NSRunLoopCommonModes];
}

- (void)removeTimer
{
    [self.timer invalidate];
    self.timer = nil;
}

- (void)update
{
    //跟新测试值
    [self.recorder updateMeters];
    float power = [self.recorder averagePowerForChannel:0];
    if (power < -20) { //静音
        self.silentDuration += self.timer.duration;
        
        if (self.silentDuration > 2) {
            [self.recorder stop];
        }
    } else{ //说话
        self.silentDuration = 0;
    }
}
- (IBAction)startRecord {
    NSString *doc = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES)lastObject];
    NSString *path = [doc stringByAppendingString:@"test.caf"];
    NSURL *url = [NSURL fileURLWithPath:path];
    
    AVAudioRecorder *recorder = [[AVAudioRecorder alloc] initWithURL:url settings:nil error:nil];
    //缓冲
    [recorder prepareToRecord];
    //录音
    [recorder record];
    
    //开启分贝测量功能
    recorder.meteringEnabled = YES;
    [recorder averagePowerForChannel:0];
    
    self.recorder = recorder;
}

- (IBAction)stopRecord {
    [self.recorder stop];
}
@end