Add support for extracting 32-bit float WAVE

Issue: #3379

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=179925320

RELEASENOTES.md

@@ -36,6 +36,8 @@
 * DefaultTrackSelector: Support disabling of individual text track selection
 * DefaultTrackSelector: Support disabling of individual text track selection
   flags.
   flags.
 * New Cast extension: Simplifies toggling between local and Cast playbacks.
 * New Cast extension: Simplifies toggling between local and Cast playbacks.
+* Add support for extracting 32-bit WAVE files
+ ([#3379](https://github.com/google/ExoPlayer/issues/3379)).
 
 
 ### 2.6.1 ###
 ### 2.6.1 ###
 
 

library/core/src/main/java/com/google/android/exoplayer2/extractor/wav/WavHeaderReader.java

@@ -31,6 +31,8 @@ import java.io.IOException;
 
 
   /** Integer PCM audio data. */
   /** Integer PCM audio data. */
   private static final int TYPE_PCM = 0x0001;
   private static final int TYPE_PCM = 0x0001;
+  /** Float PCM audio data. */
+  private static final int TYPE_FLOAT = 0x0003;
   /** Extended WAVE format. */
   /** Extended WAVE format. */
   private static final int TYPE_WAVE_FORMAT_EXTENSIBLE = 0xFFFE;
   private static final int TYPE_WAVE_FORMAT_EXTENSIBLE = 0xFFFE;
 
 
@@ -87,14 +89,22 @@ import java.io.IOException;
           + blockAlignment);
           + blockAlignment);
     }
     }
 
 
-    @C.PcmEncoding int encoding = Util.getPcmEncoding(bitsPerSample);
-    if (encoding == C.ENCODING_INVALID) {
-      Log.e(TAG, "Unsupported WAV bit depth: " + bitsPerSample);
+    @C.PcmEncoding int encoding;
+    switch (type) {
+      case TYPE_PCM:
+      case TYPE_WAVE_FORMAT_EXTENSIBLE:
+        encoding = Util.getPcmEncoding(bitsPerSample);
+        break;
+      case TYPE_FLOAT:
+        encoding = bitsPerSample == 32 ? C.ENCODING_PCM_FLOAT : C.ENCODING_INVALID;
+        break;
+      default:
+        Log.e(TAG, "Unsupported WAV format type: " + type);
         return null;
         return null;
     }
     }
 
 
-    if (type != TYPE_PCM && type != TYPE_WAVE_FORMAT_EXTENSIBLE) {
-      Log.e(TAG, "Unsupported WAV format type: " + type);
+    if (encoding == C.ENCODING_INVALID) {
+      Log.e(TAG, "Unsupported WAV bit depth " + bitsPerSample + " for type " + type);
       return null;
       return null;
     }
     }