AVAudioRecorder
0 使用前准备
这是一个录制音频的类.1.需要设置AVAudioSession.2.需要在info.plist中添加相应的字段
0.1 设置AVAudioSession接收音频输入
NSError *error;
AVAudioSession *session = [AVAudioSession sharedInstance];
if ([session setCategory:AVAudioSessionCategoryPlayAndRecord error:&error]) {
// 处理错误
}
0.2 在info.plist中添加对应字段
Privacy - Microphone Usage Description(NSMicrophoneUsageDescription).后面的内容是为什么要使用麦克风的说明.一般的套路就是.
需要使用您的麦克风来干XXX,如果不同意,则xxx功能不能使用.这个得注意,不填不能过审.
1 类介绍
/// 创建方法
- (nullable instancetype)initWithURL:(NSURL *)url settings:(NSDictionary *)settings error:(NSError **)outError;
- (nullable instancetype)initWithURL:(NSURL *)url format:(AVAudioFormat *)format error:(NSError **)outError API_AVAILABLE(macos(10.12), ios(10.0), watchos(4.0)) API_UNAVAILABLE(tvos);
/// 创建音频文件并准备进行录制(调用record时,会自动调用.)该方法会在initWithURL: setting: error方法中的url的位置创建音频文件,如果该位置已经有此文件,该方法将会覆盖该文件.
- (BOOL)prepareToRecord;
/// 开始/恢复 录制.(PS:内部会自动调用prepareToRecord)
- (BOOL)record;
/// 将在time秒后继续录制.time得(myAudioRecorder.deviceCurrentTime + time)
- (BOOL)recordAtTime:(NSTimeInterval)time API_AVAILABLE(macos(10.9), ios(6.0), watchos(4.0)) API_UNAVAILABLE(tvos);
/// 录制持续时间(duration)后就会自动停止
- (BOOL)recordForDuration:(NSTimeInterval) duration;
/// time秒后开始录制.然后duration秒后停止
- (BOOL)recordAtTime:(NSTimeInterval)time forDuration:(NSTimeInterval) duration API_AVAILABLE(macos(10.9), ios(6.0), watchos(4.0)) API_UNAVAILABLE(tvos); /* record a file of a specified duration starting at specified time. time is an absolute time based on and greater than deviceCurrentTime. */
/// 暂停录制
- (void)pause;
/// 停止录制.关闭文件输出
- (void)stop;
/// 删除录制(必须得先调用stop方法)
- (BOOL)deleteRecording;
/* 属性 */
/// 录音机是否正在录制
@property(readonly, getter=isRecording) BOOL recording;
/// 录制文件的url
@property(readonly) NSURL *url;
/// 录制设置
@property(readonly) NSDictionary *settings;
/// format
@property(readonly) AVAudioFormat *format API_AVAILABLE(macos(10.12), ios(10.0), watchos(4.0)) API_UNAVAILABLE(tvos);
/// 代理
@property(weak, nullable) id delegate;
/// 当前的录制时间.仅在录制时有效
@property(readonly) NSTimeInterval currentTime;
/// 获取设备当前时间,始终有效
@property(readonly) NSTimeInterval deviceCurrentTime API_AVAILABLE(macos(10.9), ios(6.0), watchos(4.0)) API_UNAVAILABLE(tvos);
/* 计量 */
/// 是否能计量
@property(getter=isMeteringEnabled) BOOL meteringEnabled; /* turns level metering on or off. default is off. */
/// 更新计量
- (void)updateMeters;
/// 返回通道的峰值功率(分贝值)
- (float)peakPowerForChannel:(NSUInteger)channelNumber; /* returns peak power in decibels for a given channel */
/// 返回通道的平均功率(分贝值)
- (float)averagePowerForChannel:(NSUInteger)channelNumber; /* returns average power in decibels for a given channel */
/// 可以设置记录通道
@property(nonatomic, copy, nullable) NSArray *channelAssignments API_AVAILABLE(ios(7.0), watchos(4.0)) API_UNAVAILABLE(macos) API_UNAVAILABLE(tvos); /* Array of AVAudioSessionChannelDescription objects */
@end
AVAudioRecorderDelegate
/// 录制完成时调用,如果因为中断停止,就不会调用这个方法
- (void)audioRecorderDidFinishRecording:(AVAudioRecorder *)recorder successfully:(BOOL)flag;
/// 录音机发生错误回调
- (void)audioRecorderEncodeErrorDidOccur:(AVAudioRecorder *)recorder error:(NSError * __nullable)error;
/// MAKR: iOS有关
/// 开始打断
- (void)audioRecorderBeginInterruption:(AVAudioRecorder *)recorder NS_DEPRECATED_IOS(2_2, 8_0);
/// 打断结束后调用
- (void)audioRecorderEndInterruption:(AVAudioRecorder *)recorder NS_DEPRECATED_IOS(2_2, 6_0);
/// 打断结束后调用.如果调用该方法就不调用上面的方法.
- (void)audioRecorderEndInterruption:(AVAudioRecorder *)recorder withOptions:(NSUInteger)flags NS_DEPRECATED_IOS(6_0, 8_0);
/// 打断结束后调用.如果调用该方法就不会调用上面的方法
- (void)audioRecorderEndInterruption:(AVAudioRecorder *)recorder withFlags:(NSUInteger)flags NS_DEPRECATED_IOS(4_0, 6_0);
AVAudioRecorder相关参数
formatsKey
AVFormatIDKey (音频格式)
CF_ENUM(AudioFormatID)
{
kAudioFormatLinearPCM = 'lpcm',
kAudioFormatAC3 = 'ac-3',
kAudioFormat60958AC3 = 'cac3',
kAudioFormatAppleIMA4 = 'ima4',
kAudioFormatMPEG4AAC = 'aac ',
kAudioFormatMPEG4CELP = 'celp',
kAudioFormatMPEG4HVXC = 'hvxc',
kAudioFormatMPEG4TwinVQ = 'twvq',
kAudioFormatMACE3 = 'MAC3',
kAudioFormatMACE6 = 'MAC6',
kAudioFormatULaw = 'ulaw',
kAudioFormatALaw = 'alaw',
kAudioFormatQDesign = 'QDMC',
kAudioFormatQDesign2 = 'QDM2',
kAudioFormatQUALCOMM = 'Qclp',
kAudioFormatMPEGLayer1 = '.mp1',
kAudioFormatMPEGLayer2 = '.mp2',
kAudioFormatMPEGLayer3 = '.mp3',
kAudioFormatTimeCode = 'time',
kAudioFormatMIDIStream = 'midi',
kAudioFormatParameterValueStream = 'apvs',
kAudioFormatAppleLossless = 'alac',
kAudioFormatMPEG4AAC_HE = 'aach',
kAudioFormatMPEG4AAC_LD = 'aacl',
kAudioFormatMPEG4AAC_ELD = 'aace',
kAudioFormatMPEG4AAC_ELD_SBR = 'aacf',
kAudioFormatMPEG4AAC_ELD_V2 = 'aacg',
kAudioFormatMPEG4AAC_HE_V2 = 'aacp',
kAudioFormatMPEG4AAC_Spatial = 'aacs',
kAudioFormatMPEGD_USAC = 'usac',
kAudioFormatAMR = 'samr',
kAudioFormatAMR_WB = 'sawb',
kAudioFormatAudible = 'AUDB',
kAudioFormatiLBC = 'ilbc',
kAudioFormatDVIIntelIMA = 0x6D730011,
kAudioFormatMicrosoftGSM = 0x6D730031,
kAudioFormatAES3 = 'aes3',
kAudioFormatEnhancedAC3 = 'ec-3',
kAudioFormatFLAC = 'flac',
kAudioFormatOpus = 'opus'
};
一般都是用AAC
AVSampleRateKey (取样率)
@44100
@8000 (电话采样率)
AVNumberOfChannelsKey (声道数)
@1 (单声道)
AVLinearPCMBitDepthKey (比特率)
8 16 24 32
AVLinearPCMIsBigEndianKey (大小端存储)
YES是大端存储,NO小端存储
AVLinearPCMIsFloatKey (采样信号是整数还是浮点数)
YES浮点数 NO整数
AVLinearPCMIsNonInterleaved
YES非交错 NO交错
音频类型key
AVAudioFileTypeKey (音频文件类型)
AVEncoderAudioQualityKey (音频编码质量)
typedef NS_ENUM(NSInteger, AVAudioQuality) {
AVAudioQualityMin = 0,
AVAudioQualityLow = 0x20,
AVAudioQualityMedium = 0x40,
AVAudioQualityHigh = 0x60,
AVAudioQualityMax = 0x7F
};
AVEncoderAudioQualityForVBRKey (动态比特率)
值为AVAudioQuality类型
AVEncoderBitRateKey (编码比特率)
AVEncoderBitRatePerChannelKey (每个声道的比特率)
属性值
AVEncoderBitRateStrategyKey (编码比特率策略)
/* values for AVEncoderBitRateStrategyKey */
extern NSString *const AVAudioBitRateStrategy_Constant API_AVAILABLE(macos(10.9), ios(7.0), watchos(2.0), tvos(9.0));
extern NSString *const AVAudioBitRateStrategy_LongTermAverage API_AVAILABLE(macos(10.9), ios(7.0), watchos(2.0), tvos(9.0));
extern NSString *const AVAudioBitRateStrategy_VariableConstrained API_AVAILABLE(macos(10.9), ios(7.0), watchos(2.0), tvos(9.0));
extern NSString *const AVAudioBitRateStrategy_Variable API_AVAILABLE(macos(10.9), ios(7.0), watchos(2.0), tvos(9.0));
AVEncoderBitDepthHintKey
取值范围8 - 32
AVSampleRateConverterAlgorithmKey
extern NSString *const AVSampleRateConverterAlgorithm_Normal API_AVAILABLE(macos(10.9), ios(7.0), watchos(2.0), tvos(9.0));
extern NSString *const AVSampleRateConverterAlgorithm_Mastering API_AVAILABLE(macos(10.9), ios(7.0), watchos(2.0), tvos(9.0));
extern NSString *const AVSampleRateConverterAlgorithm_MinimumPhase API_AVAILABLE(macos(10.12), ios(10.0), watchos(3.0), tvos(10.0));
AVSampleRateConverterAudioQualityKey
AVChannelLayoutKey
返回NSData类型.
用例
AVAudioSession *session = [AVAudioSession sharedInstance];
if ([session setCategory:AVAudioSessionCategoryPlayAndRecord error:nil]) {
}
NSURL *url = [NSURL fileURLWithPath:[NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES).firstObject stringByAppendingPathComponent:@"/录音.MP3"]];
NSError *error;
self.audioRecorder = [[AVAudioRecorder alloc] initWithURL:url settings:@{AVFormatIDKey :@(kAudioFormatMPEG4AAC),
AVSampleRateKey :@(8000),
AVNumberOfChannelsKey :@(1),
AVLinearPCMBitDepthKey :@(8),
AVLinearPCMIsFloatKey :@(YES)
} error:&error];
self.audioRecorder.delegate = self;
[self.audioRecorder prepareToRecord];
[self.audioRecorder record];