Audio Changes to in-editor waveform generation in 5.4?

You could try this which displays the selected audioclip in a separate window, but it still relies on reflection, so no guarantees this won't change at some point:

Code (CSharp):

1. using UnityEngine;
2. using UnityEditor;
3. using System.Collections;
4. using System.Reflection;
5.  
6. public class RenderWave : EditorWindow
7. {
8.     [MenuItem("Window/Waveform")]
9.     public static void ShowWindow()
10.     {
11.         EditorWindow.GetWindow(typeof(RenderWave));
12.     }
13.  
14.     void OnGUI()
15.     {
16.         var clip = Selection.activeObject as AudioClip; if (clip == null) return;
17.         var path = AssetDatabase.GetAssetPath (clip); if (path == null) return;
18.         var importer = AssetImporter.GetAtPath (path); if (importer == null) return;
19.         var assembly = Assembly.GetAssembly (typeof (AssetImporter)); if (assembly == null) return;
20.         var type = assembly.GetType ("UnityEditor.AudioUtil"); if (type == null) return;
21.         var AudioUtil_GetMinMaxData = type.GetMethod ("GetMinMaxData"); if (AudioUtil_GetMinMaxData == null) return;
22.         var minMaxData = AudioUtil_GetMinMaxData.Invoke (null, new object[] { importer }) as float[]; if (minMaxData == null) return;
23.  
24.         var r = EditorGUILayout.GetControlRect (GUILayout.ExpandWidth (true), GUILayout.ExpandHeight (true));
25.         var curveColor = new Color (255 / 255f, 168 / 255f, 7 / 255f);
26.         int numChannels = clip.channels;
27.         int numSamples = minMaxData.Length / (2 * numChannels);
28.         float h = (float)r.height / numChannels;
29.         for (int channel = 0; channel < numChannels; channel++)
30.         {
31.             var channelRect = new Rect (r.x, r.y + channel * h, r.width, h);
32.             AudioCurveRendering.DrawMinMaxFilledCurve(
33.                 channelRect,
34.                 delegate(float x, out Color col, out float minValue, out float maxValue)
35.                 {
36.                     col = curveColor;
37.                     float p = Mathf.Clamp(x * (numSamples - 2), 0.0f, numSamples - 2);
38.                     int i = (int)Mathf.Floor(p);
39.                     int offset1 = (i * numChannels + channel) * 2;
40.                     int offset2 = offset1 + numChannels * 2;
41.                     minValue = Mathf.Min(minMaxData[offset1 + 1], minMaxData[offset2 + 1]);
42.                     maxValue = Mathf.Max(minMaxData[offset1 + 0], minMaxData[offset2 + 0]);
43.                     if (minValue > maxValue) { float tmp = minValue; minValue = maxValue; maxValue = tmp; }
44.                 }
45.             );
46.         }
47.     }
48. }
49.