IOS 录音

//录音设置

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

//设置录音格式AVFormatIDKey==kAudioFormatLinearPCM

[recordSetting setValue:[NSNumber numberWithInt:kAudioFormatMPEG4AAC] forKey:AVFormatIDKey];

//设置录音采样率(Hz) 如：AVSampleRateKey==8000/44100/96000（影响音频的质量）

[recordSetting setValue:[NSNumber numberWithFloat:44100] forKey:AVSampleRateKey];

//录音通道数1 或 2

[recordSetting setValue:[NSNumber numberWithInt:1] 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];