feat(AudioVisualizationView): addition function buffering audio file

Author: bastienFalcou

SoundWave/Classes/AudioVisualizationView.swift

@@ -5,6 +5,7 @@
 //  Created by Bastien Falcou on 12/6/16.
 //
 
+import AVFoundation
 import UIKit
 
 public class AudioVisualizationView: BaseNibView {
@@ -149,6 +150,22 @@ public class AudioVisualizationView: BaseNibView {
 		return self.meteringLevelsClusteredArray
 	}
 
+    // PRAGMA: - Analyze Sound File
+
+    private func buffer(url: URL) {
+        do {
+            let track = try AVAudioFile(forReading: url)
+            let format = AVAudioFormat(commonFormat:.pcmFormatFloat32,
+                                       sampleRate:track.fileFormat.sampleRate,
+                                       channels: track.fileFormat.channelCount,
+                                       interleaved: false)
+            let buffer = AVAudioPCMBuffer(pcmFormat: format!, frameCapacity: UInt32(track.length))!
+            try track.read(into : buffer, frameCount:UInt32(track.length))
+        } catch {
+            print(error)
+        }
+    }
+
 	// PRAGMA: - Play Mode Handling
 
 	public func play(for duration: TimeInterval) {