操作无法完成.AVAudioRecorder iphone SDK

Question

我正在尝试使用iphone麦克风进行录制:这是我的代码:

NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];

// the path to write file
NSString *appFile = [documentsDirectory stringByAppendingPathComponent:@"testing.mp3"];




NSURL *url = [NSURL fileURLWithPath:appFile isDirectory:NO];

NSDictionary *settings = [NSDictionary dictionaryWithObjectsAndKeys:
                          [NSNumber numberWithFloat: 44100.0],                 AVSampleRateKey,
                          [NSNumber numberWithInt: kAudioFormatMPEGLayer3], AVFormatIDKey,
                          [NSNumber numberWithInt: 1],                         AVNumberOfChannelsKey,
                          [NSNumber numberWithInt: AVAudioQualityLow],         AVEncoderAudioQualityKey,
                          nil];

NSError *error;

recorder = [[AVAudioRecorder alloc] initWithURL:url settings:settings error:&error];

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

}

NSLog(@"BOOL = %d", (int)recorder.recording);

这是我得到的错误:

Operation could not be completed. (OSStatus error 1718449215.)

我无法弄清楚为什么这不起作用,因为我从网站获得了很多代码.

乔纳森

Answer 1

你的问题是kAudioFormatMPEGLayer3

不幸的是,你不能以mp3格式在iPhone上编码声音.目前,压缩音频的最佳格式是kAudioFormatAppleIMA4.(是的,还有kAudioFormatMPEG4AAC - 甚至更好,但它只适用于模拟器,但不适用于设备).另请注意,在其他系统(例如窗口)上解码记录的kAudioFormatAppleIMA4文件时可能会出现问题,因此对于小文件来说,简单的lpcm格式可能更方便.