編集履歴

質問編集履歴

多々変更

2018/01/24 09:31

投稿

スコア23

test CHANGED Viewed

	@@ -1 +1 @@
1	- AVAudioEngineを用いたABループ機能
1	+ AVAudioEngineを用いた指定部分ループ機能

test CHANGED Viewed

@@ -8,15 +8,49 @@
 ##質問内容
-https://qiita.com/muukii0803/items/437fa0c8038878b5a23c
-http://asmz.hatenablog.jp/entry/avaudioengine-seek-the-time-of-the-song
-上記サイトを元に、ABリピートのように自分でループしたい部分を選択できるプログラムを書きたいのですが色々といじっている内に再生さえされなかったりNSWindowがエラーを吐いたりとどうすればよいかわからなくなってしまいました。
-```
+現在、playを押すと音楽が無限ループで流れる状態です。
+そしてloopStartSettingを押してloopEndSettingを押すと、音楽が最初から流れ、StartからEndを押すまでの間を無限ループします。
+しかし音楽が2周目以降にloopStartとloopEndを設定しようとするとloopEndSettingを押したときにエラーを出します。
+そこで
+1. 音楽が２周目以降でもStartEnd間でループさせたい
+2.StartEnd間でループが始まる前に音楽が最初から流れるのをloopStartSettingを押した時点から再生させたい(イメージとしてはABリピート)
+この二点の問題を解決したいです
+よろしくお願いします
+---
+```
+try! file.read(into: loopBuffer, frameCount: frametoplay)
+```
+```エラーコード
+fatal error: 'try!' expression unexpectedly raised an error: Foundation._GenericObjCError.nilError: file /Library/Caches/com.apple.xbs/Sources/swiftlang/swiftlang-900.0.65.2/src/swift/stdlib/public/core/ErrorType.swift, line 181
+```
+```Swift4.0
 import Cocoa
@@ -24,9 +58,7 @@
-public class ViewController: NSViewController {
+class ViewController: NSViewController {
     let engine = AVAudioEngine()
@@ -34,31 +66,27 @@
-    @IBOutlet var currentTimeLabel: NSTextField!
-    @IBOutlet var totalTimeLabel: NSTextField!
-    @IBOutlet var playButtonTitle: NSButton!
     let url = Bundle.main.url(forResource: "moo", withExtension: "mp3")!
-    var loopStart: AVAudioFramePosition = 0
+    var loopStart: Double = 0
-    var loopEnd: AVAudioFramePosition = 0
+    var loopEnd: Double = 0
+    var loopBuffer = AVAudioPCMBuffer()
+    var introBuffer = AVAudioPCMBuffer()
-    @IBAction func playButton(_ sender: Any) {
+    @IBAction func play(_ sender: Any) {
+        try! engine.start()
-        if !player.isPlaying{
+        if !player.isPlaying {
             player.play()
@@ -72,75 +100,81 @@
-    func loopSetA(startFrame: Double) {
-        let file = try! AVAudioFile(forReading: url)
-        let loopStartCount = AVAudioFrameCount(AVAudioFramePosition(startFrame))
-        let loopStartBuffer = AVAudioPCMBuffer(pcmFormat: file.processingFormat, frameCapacity: loopStartCount)!
-        try! file.read(into: loopStartBuffer, frameCount: loopStartCount)
-        player.scheduleBuffer(loopStartBuffer, at: nil, options: .interrupts)
-    }
-    func loopSetB(endFrame: Double, loopStart: AVAudioFrameCount) {
-        let file = try! AVAudioFile(forReading: url)
-        let loopFrameCount = AVAudioFrameCount(endFrame) - AVAudioFrameCount(loopStart)
-        let loopFrameBuffer = AVAudioPCMBuffer(pcmFormat: file.processingFormat, frameCapacity: loopFrameCount)!
-        try! file.read(into: loopFrameBuffer, frameCount: loopFrameCount)
-        player.scheduleBuffer(loopFrameBuffer, at: nil, options: .loops)
-    }
+    @IBAction func pause(_ sender: Any) {
+        player.pause()
+    }
+    func loopControl() {
+        let file = try! AVAudioFile(forReading: url)
+        let sampleRate = file.fileFormat.sampleRate
+        let newsampleTime = AVAudioFrameCount(sampleRate * loopStart) //シーク位置(AVAudioFramePositon)取得
+        let length = loopEnd - loopStart   //残り時間取得(秒)
+        let frametoplay = AVAudioFrameCount(sampleRate * length)
+        introBuffer = AVAudioPCMBuffer(pcmFormat: file.processingFormat, frameCapacity: newsampleTime)!//Aを押すまでのバッファ
+        loopBuffer = AVAudioPCMBuffer(pcmFormat: file.processingFormat, frameCapacity: frametoplay)!//AからBまでのバッファ
+        try! file.read(into: introBuffer, frameCount: newsampleTime)
+        try! file.read(into: loopBuffer, frameCount: frametoplay)
+        player.stop()
+        if frametoplay > 100 {
+            player.scheduleBuffer(introBuffer, at: nil, completionHandler: nil)
+            player.scheduleBuffer(loopBuffer, at: nil, options: .loops, completionHandler: nil)
+        }
+        player.play()
+    }
     @IBAction func loopStartSetting(_ sender: Any) {
-        if loopStart == 0{
-            let startNodeTime = player.lastRenderTime
-            let startPlayerTime = player.playerTime(forNodeTime: startNodeTime!)
+        let file = try! AVAudioFile(forReading: url)
-            let currentFrame = Double(startPlayerTime!.sampleRate)
+        let sampleRate = file.fileFormat.sampleRate
-            loopStart = AVAudioFramePosition(currentFrame)
-            loopSetA(startFrame: currentFrame)
-        }else{
-            let endNodeTime = player.lastRenderTime
+        let nodeTime = player.lastRenderTime
-            let endPlayerTime = player.playerTime(forNodeTime: endNodeTime!)
+        let playerTime = player.playerTime(forNodeTime: nodeTime!)
-            let endFrame = Double(endPlayerTime!.sampleRate)
+        loopStart = (Double(playerTime!.sampleTime) / sampleRate)
-            loopSetB(endFrame: endFrame, loopStart: AVAudioFrameCount(loopStart))
-        }
     }
@@ -148,13 +182,27 @@
     @IBAction func loopEndSetting(_ sender: Any) {
+        let file = try! AVAudioFile(forReading: url)
+        let sampleRate = file.fileFormat.sampleRate
+        let nodeTime = player.lastRenderTime
+        let playerTime = player.playerTime(forNodeTime: nodeTime!)
+        loopEnd = (Double(playerTime!.sampleTime) / sampleRate)
+        loopControl()
-    }
+    }
-    override public func viewDidLoad() {
+    override func viewDidLoad() {
         super.viewDidLoad()
@@ -162,7 +210,7 @@
         engine.attach(player)
         let file = try! AVAudioFile(forReading: url)
@@ -170,56 +218,16 @@
         let totalFrameCount = AVAudioFrameCount(file.length)
-        let loopStartCount = AVAudioFrameCount(loopStart)
-        let loopFrameCount = totalFrameCount - loopStartCount
-        //イントロとループ部のバッファ作成
-        let loopStartBuffer = AVAudioPCMBuffer(pcmFormat: file.processingFormat, frameCapacity: loopStartCount)!
-        let loopFrameBuffer = AVAudioPCMBuffer(pcmFormat: file.processingFormat, frameCapacity: loopFrameCount)!
+        let totalFrameBuffer = AVAudioPCMBuffer(pcmFormat: file.processingFormat, frameCapacity: totalFrameCount)
-        try! file.read(into: loopStartBuffer, frameCount: loopStartCount)
-        try! file.read(into: loopFrameBuffer, frameCount: loopFrameCount)
+        try! file.read(into: totalFrameBuffer!, frameCount: totalFrameCount)
-        player.scheduleBuffer(loopStartBuffer, at: nil, options: .interrupts)
-        player.scheduleBuffer(loopFrameBuffer, at: nil, options: .loops)
         engine.connect(player, to: engine.mainMixerNode, format: file.processingFormat)
-        try! engine.start()
+        player.scheduleBuffer(totalFrameBuffer!, at: nil, options: .loops, completionHandler: nil)
-    }
+    }
-    override public var representedObject: Any? {
-        didSet {
-        // Update the view, if already loaded.
-        }
-    }
-}
-```
+```
-機能としてはAボタンを押してその後Bボタンを押すとAB間がループする、もしくは同じぼんを１回押して、少し間を開けてもう１回押すと２回めに押すまでに流れた音楽がリピートするといったものを目指しています。
-ご回答よろしくお願いします