IPhone之AVAudioRecorder

#import 需要引入

1. //获取document目录的路径
2. view plain
3. - (NSString*) documentsPath {
4. if (! _documentsPath) {
5. NSArray *searchPaths =
6. NSSearchPathForDirectoriesInDomains
7. (NSDocumentDirectory, NSUserDomainMask, YES);
8. _documentsPath = [searchPaths objectAtIndex: 0];
9. [_documentsPath retain];
10. }
11. return _documentsPath;
12. }
13. //(document目录的路径)
14. NSString *destinationString = [[self documentsPath]
15. stringByAppendingPathComponent:filenameField.text];
16. NSURL *destinationURL = [NSURL fileURLWithPath: destinationString];
17. //初始化AVAudioRecorder
18. NSError *recorderSetupError = nil;
19. AVAudioRecorder audioRecorder = [[AVAudioRecorder alloc] initWithURL:destinationURL
20. settings:recordSettings error:&recorderSetupError];
21. [recordSettings release];

第二个参数 settings是一个容纳键值对的NSDictionary有四种一般的键

1:一般的音频设置

2:线性PCM设置

3:编码器设置

4:采样率转换设置

NSMutableDictionary 需要加入五个设置值(线性PCM)

1. NSMutableDictionary *recordSettings =
2. [[NSMutableDictionary alloc] initWithCapacity:10];
3. //1 ID号
4. [recordSettings setObject:
5. [NSNumber numberWithInt: kAudioFormatLinearPCM] forKey: AVFormatIDKey];
6. float sampleRate =
7. [pcmSettingsViewController.sampleRateField.text floatValue];
8. //2 采样率
9. [recordSettings setObject:
10. [NSNumber numberWithFloat:sampleRate] forKey: AVSampleRateKey];
11. //3 通道的数目
12. [recordSettings setObject:
13. [NSNumber numberWithInt:
14. (pcmSettingsViewController.stereoSwitch.on ? 2 : 1)]
15. forKey:AVNumberOfChannelsKey];
16. int bitDepth =
17. [pcmSettingsViewController.sampleDepthField.text intValue];
18. //4 采样位数 默认 16
19. [recordSettings setObject:
20. [NSNumber numberWithInt:bitDepth] forKey:AVLinearPCMBitDepthKey];
21. //5
22. [recordSettings setObject:
23. [NSNumber numberWithBool:
24. pcmSettingsViewController.bigEndianSwitch.on]
25. forKey:AVLinearPCMIsBigEndianKey];
26. //6 采样信号是整数还是浮点数
27. [recordSettings setObject:
28. [NSNumber numberWithBool:
29. pcmSettingsViewController.floatingSamplesSwitch.on]
30. forKey:AVLinearPCMIsFloatKey]
31. ;

AVAudioRecorder成功创建后,使用他非常直接.它的三个基本方法如下

1. -(void) startRecording {
2. [audioRecorder record];
3. }
4. -(void) pauseRecording {
5. [audioRecorder pause];
6. recordPauseButton.selected = NO;
7. }
8. -(void) stopRecording {
9. [audioRecorder stop];
10. }