ios におけるサウンド処理2015
TRANSCRIPT
iOSにおけるサウンド処理2015
• me.name = “Tamiya Tokihiko”
• me.company = “Classmethod, Inc.”
• company.blog = “Developers.IO”
自己紹介（プロパティ）
概要• AVAudioEngine
• iOS 8 から加わったクラス
• Audio Unit Extension
• iOS 9 で追加されたExtension Point
• Audio Unit をアプリ間で共有できる
• AVAudioSessionModeSpokenAudio
• 声コンテンツが他アプリの音声の妨げにならない仕組み
AVAudioEngine
このままだと不便
© Apple
© Apple
AVFoudation が拡充
© Apple
© Apple
AVAudioEngine
AVAudioPlayerNode
AVAudioUnit Delay
AVAudioMixerNode
AVAudio OutputNodeAVAudioFile
@property (nonatomic, strong) AVAudioEngine *engine;
@property (nonatomic, strong) AVAudioPlayerNode *audioPlayerNode;
@property (nonatomic, strong) AVAudioFile *audioFile;
@property (nonatomic, strong) AVAudioUnitDelay *audioUnitDelay;
プロパティ
self.engine = [AVAudioEngine new]; NSString *path = [[NSBundle mainBundle] pathForResource:@"loop.m4a" ofType:nil];
self.audioFile = [[AVAudioFile alloc] initForReading:[NSURL fileURLWithPath:path] error:nil];
AVAudioEngine と AVAudioFile
AVAudioEngine
self.audioPlayerNode = [AVAudioPlayerNode new];
[self.engine attachNode:self.audioPlayerNode];
AVAudioPlayerNode
AVAudioEngine
AVAudioPlayerNode
self.audioUnitDelay = [AVAudioUnitDelay new];
self.audioUnitDelay.wetDryMix = 50;
[self.engine attachNode:self.audioUnitDelay];
AVAudioEngine
AVAudioPlayerNode
AVAudioUnit Delay
AVAudioUnitDelay
AVAudioMixerNode *mixerNode = [self.engine mainMixerNode];
AVAudioEngine
AVAudioPlayerNode
AVAudioUnit Delay
AVAudioMixerNode
AVAudioMixerNode を生成
[self.engine connect:self.audioPlayerNode to:self.audioUnitDelay format:self.audioFile.processingFormat];
AVAudioEngine
AVAudioPlayerNode
AVAudioUnit Delay
AVAudioMixerNode
ノード同士をつなぐ
[self.engine connect:self.audioUnitDelay to:mixerNode format:self.audioFile.processingFormat];
AVAudioEngine
AVAudioPlayerNode
AVAudioUnit Delay
AVAudioMixerNode
ノード同士をつなぐ
NSError *error;
[self.engine startAndReturnError:&error];
AVAudioEngine
AVAudioPlayerNode
AVAudioUnit Delay
AVAudioMixerNode
AVAudioPlayerNodeで 音を再生
AVAudioEngine
AVAudioPlayerNode
AVAudioUnit Delay
AVAudioMixerNode
[self.audioPlayerNode scheduleFile:self.audioFile atTime:nil completionHandler:^() {}];
AVAudio OutputNodeAVAudioFile
/*! @property delayTime Time taken by the delayed input signal to reach the output @abstract Range: 0 -> 2 Default: 1 Unit: Seconds */ @property (nonatomic) NSTimeInterval delayTime;
/*! @property feedback @abstract Amount of the output signal fed back into the delay line Range: -100 -> 100 Default: 50 Unit: Percent */ @property (nonatomic) float feedback;
AVAudioUnitDelay.h
/*! @property lowPassCutoff @abstract Cutoff frequency above which high frequency content is rolled off Range: 10 -> (samplerate/2) Default: 15000 Unit: Hertz */ @property (nonatomic) float lowPassCutoff;
/*! @property wetDryMix @abstract Blend of the wet and dry signals Range: 0 (all dry) -> 100 (all wet) Default: 100 Unit: Percent */ @property (nonatomic) float wetDryMix;
AVAudioUnitDelay.h
demo
AudioUnitExtension
© Apple
AVAudioPlayerNode
AVAudioUnit Delay
AVAudioMixerNode
AVAudio OutputNodeAVAudioFile
@property (nonatomic) AVAudioEngine *engine;
@property (nonatomic) AVAudioPlayerNode *audioPlayerNode;
@property (nonatomic) AVAudioFile *file;
@property (nonatomic) AUAudioUnit *audioUnit;
@property (nonatomic) AVAudioUnit *effect;
@property (nonatomic) NSArray *items;
プロパティ
self.audioPlayerNode = [AVAudioPlayerNode new];
self.engine = [AVAudioEngine new];
self.effect = [AVAudioUnit new];
[self.engine attachNode:self.audioPlayerNode];
[self.engine connect:self.audioPlayerNode to:self.engine.mainMixerNode format:self.file.processingFormat];
ノード同士をつなぐ
AVAudioUnitComponent が入った配列を取得
AudioComponentDescription anyEffectDescription;
anyEffectDescription.componentType = kAudioUnitType_Effect;
anyEffectDescription.componentSubType = 0; anyEffectDescription.componentManufacturer = 0; anyEffectDescription.componentFlags = 0; anyEffectDescription.componentFlagsMask = 0; self.items = [[AVAudioUnitComponentManager sharedAudioUnitComponentManager] componentsMatchingDescription:anyEffectDescription];
- (void)viewWillAppear:(BOOL)animated { [super viewWillAppear:animated]; [self.engine startAndReturnError:nil]; [self scheduleLoop]; [self.audioPlayerNode play]; }
- (void)scheduleLoop { [self.audioPlayerNode scheduleFile:self.file atTime:nil completionHandler:^{ [self scheduleLoop]; }]; }
AVAudioPlayerNode 再生
[self.audioPlayerNode pause]; [self.engine disconnectNodeInput:self.effect]; [self.engine disconnectNodeInput:self.engine.mainMixerNode]; [self.engine connect:self.audioPlayerNode to:self.engine.mainMixerNode format:self.file.processingFormat]; self.effect = nil; self.audioUnit = nil;
ノードをつなぎ直す
self.effect = audioUnit;
（略）
[self.engine connect:self.audioPlayerNode to:self.effect format:self.file.processingFormat];
[self.engine connect:self.effect to:self.engine.mainMixerNode format:self.file.processingFormat];
特定のエフェクトを実現する AVAudioUnit を取得
[AVAudioUnit instantiateWithComponentDescription:componentDescription options:kAudioComponentInstantiation_LoadOutOfProcess completionHandler:^(__kindof AVAudioUnit * _Nullable audioUnit, NSError * _Nullable error) {}];
AVAudioUnit を使いノードをつなぐ
AVAudioUnitComponent *auComponent = self.items[indexPath.row - 1];
auComponent.name;
auComponent.manufacturerName;
AVAudioUnitComponent の名前・製造元
auComponent = self.items[indexPath.row - 1];
[self selectEffectWithComponentDescription:auComponent.audioComponentDescription];
[self.audioUnit requestViewControllerWithCompletionHandler:^(AUViewController * _Nullable viewController) {}];
独自の View を持っている場合 取得
demo
AVAudioSessionMode SpokenAudio
声のコンテンツでありがちな問題
聞き逃した！
Podcast に切替え
巻き戻し早送り 再生
AVAudioSessionCategoryOptionInterrupt SpokenAudioAndMixWithOthers
AVAudioSessionModeSpokenAudio
一時停止 ちょっと巻き戻し
概要• AVAudioEngine
• iOS 8 から加わったクラス
• Audio Unit Extension
• iOS 9 で追加されたExtension Point
• Audio Unit をアプリ間で共有できる
• AVAudioSessionModeSpokenAudio
• 声コンテンツが他アプリの音声の妨げにならない仕組み