转自 tusm 写的一个录屏Demo，在此贴下Demo的源代码方便使用
使用的是AVFoundation 录制后麦克风输入的音频，录制结束后将数据转成了mp3格式并保存成文件
// // ViewController.m // AudioDemo // // Created by tusm on 15/2/14. // Copyright (c) 2015年 tusm. All rights reserved. // #import "ViewController.h" #import <AVFoundation/AVFoundation.h> #import "lame.h" #define SCREEN_WIDTH ([UIScreen mainScreen].bounds.size.width) #define SCREEN_HEIGHT ([UIScreen mainScreen].bounds.size.height) #define NAVBAR_HEIGHT 40 #define TITLE_X (SCREEN_WIDTH/2-SCREEN_WIDTH/10) #define TITLE_Y (1.5*NAVBAR_HEIGHT) #define TITLE_WIDTH (SCREEN_WIDTH/5) #define TITLE_HEIGHT NAVBAR_HEIGHT #define RECORDBAR_X (SCREEN_WIDTH/2-SCREEN_WIDTH/4) #define RECORDBAR_Y (TITLE_Y+TITLE_HEIGHT+NAVBAR_HEIGHT/2) #define RECORDBAR_WIDTH (SCREEN_WIDTH/2) #define TIME_X (SCREEN_WIDTH/2-SCREEN_WIDTH/8) #define TIME_Y (RECORDBAR_Y+NAVBAR_HEIGHT) #define TIME_WIDTH (SCREEN_WIDTH/4) #define TIME_HEIGHT NAVBAR_HEIGHT #define RECORDBUTTON_X (SCREEN_WIDTH/2-SCREEN_WIDTH/6) #define RECORDBUTTON_Y (TIME_Y+TIME_HEIGHT+NAVBAR_HEIGHT/2) #define RECORDBUTTON_WIDTH (SCREEN_WIDTH/3) #define RECORDBUTTON_HEIGHT RECORDBUTTON_WIDTH #define PLAYBUTTON_X (SCREEN_WIDTH/2-SCREEN_WIDTH/8) #define PLAYBUTTON_Y (TIME_Y+2*TIME_HEIGHT) #define PLAYBUTTON_WIDTH SCREEN_WIDTH/4 #define PLAYBUTTON_HEIGHT PLAYBUTTON_WIDTH #define RECORE_BUTTON_TAG 1010 #define NEW_PLAY_BUTTON_TAG 1011 #define PAUSE_PLAY_BUTTON_TAG 1012 #define FINISH_BUTTON_TAG 1013 #define RECORDAGAIN_BUTTON_TAG 1014 #define PAUSE_BUTTON_TAG 1015 @implementation ViewController { UILabel* recordTitleLabel; UISlider* progressView; UILabel* timeLabel; UIButton* recordButton; UILabel* recordLabel; NSTimer* timer; int recordTime; int playTime; int playDuration; int second; int minute; UIButton* playButton; UIButton* finishButton; UIButton* pauseButton; UIButton* recordAgainButton; UILabel* playLabel; UILabel* finishLabel; UILabel* pauseLabel; UILabel* recordAgainLabel; AVAudioRecorder *audioRecorder; AVAudioPlayer *audioPlayer; AVAudioSession * audioSession; NSURL* recordUrl; NSURL* mp3FilePath; NSURL* audioFileSavePath; } - (void)viewDidLoad { [self initializeUI]; } - (void)initializeUI { playButton = [[UIButton alloc] initWithFrame:CGRectMake(PLAYBUTTON_X, PLAYBUTTON_Y, PLAYBUTTON_WIDTH, PLAYBUTTON_HEIGHT)]; [playButton setImage:[UIImage imageNamed:@"play_button.png"] forState:UIControlStateNormal]; playButton.tag = NEW_PLAY_BUTTON_TAG; [playButton addTarget:self action:@selector(clickOnButton:) forControlEvents:UIControlEventTouchUpInside]; playLabel = [[UILabel alloc] initWithFrame:CGRectMake(PLAYBUTTON_X, PLAYBUTTON_Y+PLAYBUTTON_HEIGHT, PLAYBUTTON_WIDTH, NAVBAR_HEIGHT)]; [playLabel setText:@"播放"]; [playLabel setTextAlignment:NSTextAlignmentCenter]; pauseButton = [[UIButton alloc] initWithFrame:CGRectMake(PLAYBUTTON_X, PLAYBUTTON_Y, PLAYBUTTON_WIDTH, PLAYBUTTON_HEIGHT)]; [pauseButton setImage:[UIImage imageNamed:@"pause_button.png"] forState:UIControlStateNormal]; pauseButton.tag = PAUSE_BUTTON_TAG; [pauseButton addTarget:self action:@selector(clickOnButton:) forControlEvents:UIControlEventTouchUpInside]; pauseLabel = [[UILabel alloc] initWithFrame:CGRectMake(PLAYBUTTON_X, PLAYBUTTON_Y+PLAYBUTTON_HEIGHT, PLAYBUTTON_WIDTH, NAVBAR_HEIGHT)]; [pauseLabel setText:@"暂停"]; [pauseLabel setTextAlignment:NSTextAlignmentCenter]; finishButton = [[UIButton alloc] initWithFrame:CGRectMake(PLAYBUTTON_X-PLAYBUTTON_WIDTH-10, PLAYBUTTON_Y, PLAYBUTTON_WIDTH, PLAYBUTTON_HEIGHT)]; [finishButton setImage:[UIImage imageNamed:@"finish_button.png"] forState:UIControlStateNormal]; finishButton.tag = FINISH_BUTTON_TAG; [finishButton addTarget:self action:@selector(clickOnButton:) forControlEvents:UIControlEventTouchUpInside]; finishLabel = [[UILabel alloc] initWithFrame:CGRectMake(PLAYBUTTON_X-PLAYBUTTON_WIDTH-10, PLAYBUTTON_Y+PLAYBUTTON_HEIGHT, PLAYBUTTON_WIDTH, NAVBAR_HEIGHT)]; [finishLabel setText:@"完成"]; [finishLabel setTextAlignment:NSTextAlignmentCenter]; recordAgainButton = [[UIButton alloc] initWithFrame:CGRectMake(PLAYBUTTON_X+PLAYBUTTON_WIDTH+10, PLAYBUTTON_Y, PLAYBUTTON_WIDTH, PLAYBUTTON_HEIGHT)]; [recordAgainButton setImage:[UIImage imageNamed:@"record_again_button.png"] forState:UIControlStateNormal]; recordAgainButton.tag = RECORDAGAIN_BUTTON_TAG; [recordAgainButton addTarget:self action:@selector(clickOnButton:) forControlEvents:UIControlEventTouchUpInside]; recordAgainLabel = [[UILabel alloc] initWithFrame:CGRectMake(PLAYBUTTON_X+PLAYBUTTON_WIDTH+10, PLAYBUTTON_Y+PLAYBUTTON_HEIGHT, PLAYBUTTON_WIDTH, NAVBAR_HEIGHT)]; [recordAgainLabel setText:@"重新录制"]; [recordAgainLabel setTextAlignment:NSTextAlignmentCenter]; recordTitleLabel = [[UILabel alloc] initWithFrame:CGRectMake(TITLE_X, TITLE_Y, SCREEN_WIDTH, TITLE_HEIGHT)]; [recordTitleLabel setText:@"录制语音"]; progressView = [[UISlider alloc] initWithFrame:CGRectMake(RECORDBAR_X, RECORDBAR_Y, RECORDBAR_WIDTH, 20)]; [progressView setThumbImage:[UIImage imageNamed:@"one.png"] forState:UIControlStateNormal]; progressView.value = 0; progressView.userInteractionEnabled = NO; timeLabel = [[UILabel alloc] initWithFrame:CGRectMake(TIME_X, TIME_Y, TIME_WIDTH, TIME_HEIGHT)]; [timeLabel setText:@"00:00"]; [timeLabel setFont:[UIFont systemFontOfSize:32]]; [timeLabel setTextColor:[UIColor blackColor]]; recordButton = [[UIButton alloc] initWithFrame:CGRectMake(RECORDBUTTON_X, RECORDBUTTON_Y, RECORDBUTTON_WIDTH, RECORDBUTTON_HEIGHT)]; recordButton.tag = RECORE_BUTTON_TAG; [recordButton addTarget:self action:@selector(clickOnButton:) forControlEvents:UIControlEventTouchUpInside]; [recordButton setImage:[UIImage imageNamed:@"record_button.png"] forState:UIControlStateNormal]; recordLabel = [[UILabel alloc] initWithFrame:CGRectMake(RECORDBUTTON_X, RECORDBUTTON_Y+RECORDBUTTON_HEIGHT, RECORDBUTTON_WIDTH, NAVBAR_HEIGHT/2)]; [recordLabel setText:@"点击开始"]; [recordLabel setTextAlignment:NSTextAlignmentCenter]; //录音设置 NSMutableDictionary *recordSetting = [[NSMutableDictionary alloc] init]; //设置录音格式 AVFormatIDKey==kAudioFormatLinearPCM [recordSetting setValue:[NSNumber numberWithInt:kAudioFormatLinearPCM] forKey:AVFormatIDKey]; //设置录音采样率(Hz) 如：AVSampleRateKey==8000/44100/96000（影响音频的质量）, 采样率必须要设为11025才能使转化成mp3格式后不会失真 [recordSetting setValue:[NSNumber numberWithFloat:11025.0] forKey:AVSampleRateKey]; //录音通道数 1 或 2 ，要转换成mp3格式必须为双通道 [recordSetting setValue:[NSNumber numberWithInt:2] forKey:AVNumberOfChannelsKey]; //线性采样位数 8、16、24、32 [recordSetting setValue:[NSNumber numberWithInt:16] forKey:AVLinearPCMBitDepthKey]; //录音的质量 [recordSetting setValue:[NSNumber numberWithInt:AVAudioQualityHigh] forKey:AVEncoderAudioQualityKey]; //存储录音文件 (临时文件夹) recordUrl = [NSURL URLWithString:[NSTemporaryDirectory() stringByAppendingString:@"selfRecord.caf"]]; //初始化 audioRecorder = [[AVAudioRecorder alloc] initWithURL:recordUrl settings:recordSetting error:nil]; //开启音量检测 audioRecorder.meteringEnabled = YES; audioRecorder.delegate = self; [self.view addSubview:recordTitleLabel]; [self.view addSubview:progressView]; [self.view addSubview:timeLabel]; [self.view addSubview:recordButton]; [self.view addSubview:recordLabel]; } - (void)transformCAFToMP3 { mp3FilePath = [NSURL URLWithString:[NSTemporaryDirectory() stringByAppendingString:@"myselfRecord.mp3"]]; @try { int read, write; FILE *pcm = fopen([[recordUrl absoluteString] cStringUsingEncoding:1], "rb"); //source 被转换的音频文件位置 fseek(pcm, 4*1024, SEEK_CUR); //skip file header FILE *mp3 = fopen([[mp3FilePath absoluteString] cStringUsingEncoding:1], "wb"); //output 输出生成的Mp3文件位置 const int PCM_SIZE = 8192; const int MP3_SIZE = 8192; short int pcm_buffer[PCM_SIZE*2]; unsigned char mp3_buffer[MP3_SIZE]; lame_t lame = lame_init(); lame_set_in_samplerate(lame, 11025.0); lame_set_VBR(lame, vbr_default); lame_init_params(lame); do { read = fread(pcm_buffer, 2*sizeof(short int), PCM_SIZE, pcm); if (read == 0) write = lame_encode_flush(lame, mp3_buffer, MP3_SIZE); else write = lame_encode_buffer_interleaved(lame, pcm_buffer, read, mp3_buffer, MP3_SIZE); fwrite(mp3_buffer, write, 1, mp3); } while (read != 0); lame_close(lame); fclose(mp3); fclose(pcm); } @catch (NSException *exception) { NSLog(@"%@",[exception description]); } @finally { audioFileSavePath = mp3FilePath; NSLog(@"MP3生成成功: %@",audioFileSavePath); UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"mp3转化成功！" message:nil delegate:self cancelButtonTitle:@"确定" otherButtonTitles:nil, nil]; [alert show]; } } - (void)clickOnButton:(UIButton*)sender { audioSession = [AVAudioSession sharedInstance];//得到AVAudioSession单例对象 switch (sender.tag) { case RECORE_BUTTON_TAG:{ if (![audioRecorder isRecording]) { [audioSession setCategory:AVAudioSessionCategoryPlayAndRecord error:nil];//设置类别,表示该应用同时支持播放和录音 [audioSession setActive:YES error:nil];//启动音频会话管理,此时会阻断后台音乐的播放. [audioRecorder prepareToRecord]; [audioRecorder peakPowerForChannel:0.0]; [audioRecorder record]; recordTime = 0; [self recordTimeStart]; [recordButton setImage:[UIImage imageNamed:@"recording_button.png"] forState:UIControlStateNormal]; [recordLabel setText:@"点击结束"]; } else{ [audioRecorder stop]; //录音停止 [audioSession setActive:NO error:nil]; //一定要在录音停止以后再关闭音频会话管理（否则会报错），此时会延续后台音乐播放 [timer invalidate]; //timer失效 [timeLabel setText:@"00:00"]; //时间显示复位 [progressView setValue:0 animated:YES]; //进度条复位 [recordButton removeFromSuperview]; [recordLabel removeFromSuperview]; [self.view addSubview:playButton]; [self.view addSubview:finishButton]; [self.view addSubview:recordAgainButton]; [self.view addSubview:playLabel]; [self.view addSubview:finishLabel]; [self.view addSubview:recordAgainLabel]; } } break; case NEW_PLAY_BUTTON_TAG:{ [audioSession setCategory:AVAudioSessionCategoryPlayback error:nil]; [audioSession setActive:YES error:nil]; if (mp3FilePath != nil) { audioPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL:mp3FilePath error:nil]; } else if (recordUrl != nil){ audioPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL:recordUrl error:nil]; } [audioPlayer prepareToPlay]; audioPlayer.volume = 1; [audioPlayer play]; [playButton removeFromSuperview]; [playLabel removeFromSuperview]; [self.view addSubview:pauseButton]; [self.view addSubview:pauseLabel]; playDuration = (int)audioPlayer.duration; NSLog(@"音频时长为：%i",playDuration); playTime = 0; [self audioPlayTimeStart]; } break; case PAUSE_PLAY_BUTTON_TAG:{ [audioSession setActive:YES error:nil]; [audioPlayer play]; [playButton removeFromSuperview]; [playLabel removeFromSuperview]; [self.view addSubview:pauseButton]; [self.view addSubview:pauseLabel]; } break; case PAUSE_BUTTON_TAG:{ [audioPlayer pause]; [audioSession setActive:NO error:nil]; playButton.tag = PAUSE_PLAY_BUTTON_TAG; [pauseButton removeFromSuperview]; [pauseLabel removeFromSuperview]; [self.view addSubview:playButton]; [self.view addSubview:playLabel]; } break; case FINISH_BUTTON_TAG:{ [self transformCAFToMP3]; } break; case RECORDAGAIN_BUTTON_TAG:{ [audioPlayer stop]; [audioRecorder stop]; [audioSession setActive:NO error:nil]; [timer invalidate]; progressView.value = 0; [timeLabel setText:@"00:00"]; recordTime = 0; playTime = 0; [playButton removeFromSuperview]; [pauseButton removeFromSuperview]; [finishButton removeFromSuperview]; [recordAgainButton removeFromSuperview]; [playLabel removeFromSuperview]; [pauseLabel removeFromSuperview]; [finishLabel removeFromSuperview]; [recordAgainLabel removeFromSuperview]; [self.view addSubview:recordButton]; [self.view addSubview:recordLabel]; [recordButton setImage:[UIImage imageNamed:@"record_button.png"] forState:UIControlStateNormal]; [recordLabel setText:@"点击开始"]; } break; default: break; } } - (void)recordTimeStart { timer = [NSTimer scheduledTimerWithTimeInterval:1 target:self selector:@selector(recordTimeTick) userInfo:nil repeats:YES]; } - (void)recordTimeTick { recordTime += 1; [progressView setValue:(float)recordTime/30.0 animated:YES]; if (recordTime == 30) { recordTime = 0; [audioRecorder stop]; [[AVAudioSession sharedInstance] setActive:NO error:nil]; [timer invalidate]; [timeLabel setText:@"00:00"]; [progressView setValue:0.0 animated:YES]; [recordButton removeFromSuperview]; [recordLabel removeFromSuperview]; [self.view addSubview:playButton]; [self.view addSubview:finishButton]; [self.view addSubview:recordAgainButton]; [self.view addSubview:playLabel]; [self.view addSubview:finishLabel]; [self.view addSubview:recordAgainLabel]; return; } [self updateAudioRecordTime]; } - (void)updateAudioRecordTime { minute = recordTime/60.0; second = recordTime-minute*60; [timeLabel setText:[NSString stringWithFormat:@"%02d:%02d",minute,second]]; } - (void)audioPlayTimeStart { timer = [NSTimer scheduledTimerWithTimeInterval:1 target:self selector:@selector(playTimeTick) userInfo:nil repeats:YES]; } - (void)playTimeTick { if (playDuration == playTime) { playTime = 0; [audioPlayer stop]; [[AVAudioSession sharedInstance] setActive:NO error:nil]; [pauseButton removeFromSuperview]; [pauseLabel removeFromSuperview]; [self.view addSubview:playButton]; [self.view addSubview:playLabel]; playButton.tag = NEW_PLAY_BUTTON_TAG; [timeLabel setText:@"00:00"]; [timer invalidate]; progressView.value = 0; return; } if (![audioPlayer isPlaying]) { return; } playTime += 1; [progressView setValue:(float)playTime/(float)playDuration animated:YES]; [self updateAudioPlayTime]; } - (void)updateAudioPlayTime { minute = playTime/60.0; second = playTime-minute*60; [timeLabel setText:[NSString stringWithFormat:@"%02d:%02d",minute,second]]; } //AVAudioRecorderDelegate方法 - (void)audioPlayerDidFinishPlaying:(AVAudioPlayer *)player successfully:(BOOL)flag { [audioSession setActive:NO error:nil]; playTime = 0; [pauseButton removeFromSuperview]; [pauseLabel removeFromSuperview]; [self.view addSubview:playButton]; [self.view addSubview:playLabel]; playButton.tag = NEW_PLAY_BUTTON_TAG; [timeLabel setText:@"00:00"]; [timer invalidate]; progressView.value = 0; } @end