ios，在麦克风录制音频时获取浮动电平麦克风 updateMesters

Posted 2023-02-25

【中文标题】ios，在麦克风录制音频时获取浮动电平麦克风 updateMesters

【英文标题】：ios , get float level mic updateMesters when mic is recording audio

【发布时间】：2013-02-17 17:06:25

【问题描述】：

这是我现在录制的代码如何通过示例 UIlable 浮点数获取麦克风中输入的电平声音

我想我会使用这个功能，但我如何在 rec.h 和 rec.m 文件中使用它

(void)updateMeters

AVAudiosession * audioSession = [AVAudioSession sharedInstance];
[audioSession setCategory:AVAudioSessionCategoryPlayAndRecord error:nil];
[audioSession setActive:YES error:nil];
NSMutableDictionary* recordSetting = [[NSMutableDictionary alloc] init];
[recordSetting setValue :[NSNumber numberWithInt:kAudioFormatMPEG4AAC] forKey:AVFormatIDKey];
[recordSetting setValue:[NSNumber numberWithFloat:44100.0] forKey:AVSampleRateKey];
[recordSetting setValue:[NSNumber numberWithInt: 2] forKey:AVNumberOfChannelsKey];
recordedTmpName = [[NSString alloc] initWithFormat:@"%.0f.%@", [NSDate timeIntervalSinceReferenceDate] * 1000.0, @"aac"];
temporaryRecFile= [NSURL fileURLWithPath:[NSTemporaryDirectory() stringByAppendingPathComponent:recordedTmpName]];
recorder = [[ AVAudioRecorder alloc] initWithURL:temporaryRecFile settings:recordSetting error:nil];
[recorder setDelegate:self];
[recorder prepareToRecord];
[recorder record];

【参考方案1】：

在录制过程中，您必须定期调用 updateMeters，并通过以下方式获取平均功率 - (float)averagePowerForChannel:(NSUInteger)channelNumber

[recorder setDelegate:self];
[recorder prepareToRecord];
recorder.meteringEnabled = YES;
[recorder record];
NSTimer* timer = [NSTimer scheduledTimerWithTimeInterval:0.2 target:self selector:@selector(handleTimer) userInfo:nil repeats:YES];




- (void) handleTimer

    [recorder updateMeters];
    label.text = [NSString stringWithFormat:@"lf",[recorder averagePowerForChannel:0]];

要查看更多信息，您可以访问AVAudioRecorder Class Reference