Set valid channel masks for 8 and 12 channels on all Android versions

Util.getAudioTrackChannelConfig() maps a channel count to a
channel mask that is passed to AudioTrack. The method expected that
playback of 8-channel audio is possible from Android 5.1 and playback of
12-channel audio is only possible from Android 12L. However, there is no
restriction on the upper number of channels that can be passed to the
AudioTrack. google/ExoPlayer#10701 is an example where the audio decoder
outputs 12 channels on an Android 10.

This change removes the restrictions for 8 and 12 channels. Note, we still
do not support playback of arbitrary number of channels as it would require
further changes to DefaultAudioSink.

#minor-release

Issue: google/ExoPlayer#10701
PiperOrigin-RevId: 488659831
(cherry picked from commit 491b136)

RELEASENOTES.md

@@ -52,6 +52,9 @@ Release notes
         output device ([#135](https://github.com/androidx/media/issues/135)).
     *   Rename `androidx.media3.exoplayer.audio.AudioProcessor` to
         `androidx.media3.common.audio.AudioProcessor`.
+    *   Map 8-channel and 12-channel audio to the 7.1 and 7.1.4 channel masks
+        respectively on all Android versions
+        ([#10701](https://github.com/google/ExoPlayer/issues/10701)).
 *   Metadata:
     *   `MetadataRenderer` can now be configured to render metadata as soon as
         they are available. Create an instance with

libraries/common/src/main/java/androidx/media3/common/util/Util.java

@@ -1861,6 +1861,7 @@ public static boolean isEncodingHighResolutionPcm(@C.PcmEncoding int encoding) {
    * @return The channel configuration or {@link AudioFormat#CHANNEL_INVALID} if output is not
    *     possible.
    */
+  @SuppressLint("InlinedApi") // Inlined AudioFormat constants.
   @UnstableApi
   public static int getAudioTrackChannelConfig(int channelCount) {
     switch (channelCount) {
@@ -1879,21 +1880,9 @@ public static int getAudioTrackChannelConfig(int channelCount) {
       case 7:
         return AudioFormat.CHANNEL_OUT_5POINT1 | AudioFormat.CHANNEL_OUT_BACK_CENTER;
       case 8:
-        if (SDK_INT >= 23) {
-          return AudioFormat.CHANNEL_OUT_7POINT1_SURROUND;
-        } else if (SDK_INT >= 21) {
-          // Equal to AudioFormat.CHANNEL_OUT_7POINT1_SURROUND, which is hidden before Android M.
-          return AudioFormat.CHANNEL_OUT_5POINT1
-              | AudioFormat.CHANNEL_OUT_SIDE_LEFT
-              | AudioFormat.CHANNEL_OUT_SIDE_RIGHT;
-        } else {
-          // 8 ch output is not supported before Android L.
-          return AudioFormat.CHANNEL_INVALID;
-        }
+        return AudioFormat.CHANNEL_OUT_7POINT1_SURROUND;
       case 12:
-        return Util.SDK_INT >= 32
-            ? AudioFormat.CHANNEL_OUT_7POINT1POINT4
-            : AudioFormat.CHANNEL_INVALID;
+        return AudioFormat.CHANNEL_OUT_7POINT1POINT4;
       default:
         return AudioFormat.CHANNEL_INVALID;
     }

libraries/exoplayer/src/main/java/androidx/media3/exoplayer/audio/DefaultAudioSink.java

@@ -771,16 +771,6 @@ public void configure(Format inputFormat, int specifiedBufferSize, @Nullable int
         outputChannelConfig = encodingAndChannelConfig.second;
       }
     }
-    int bufferSize =
-        specifiedBufferSize != 0
-            ? specifiedBufferSize
-            : audioTrackBufferSizeProvider.getBufferSizeInBytes(
-                getAudioTrackMinBufferSize(outputSampleRate, outputChannelConfig, outputEncoding),
-                outputEncoding,
-                outputMode,
-                outputPcmFrameSize,
-                outputSampleRate,
-                enableAudioTrackPlaybackParams ? MAX_PLAYBACK_SPEED : DEFAULT_PLAYBACK_SPEED);
 
     if (outputEncoding == C.ENCODING_INVALID) {
       throw new ConfigurationException(
@@ -791,6 +781,16 @@ public void configure(Format inputFormat, int specifiedBufferSize, @Nullable int
           "Invalid output channel config (mode=" + outputMode + ") for: " + inputFormat,
           inputFormat);
     }
+    int bufferSize =
+        specifiedBufferSize != 0
+            ? specifiedBufferSize
+            : audioTrackBufferSizeProvider.getBufferSizeInBytes(
+                getAudioTrackMinBufferSize(outputSampleRate, outputChannelConfig, outputEncoding),
+                outputEncoding,
+                outputMode,
+                outputPcmFrameSize,
+                outputSampleRate,
+                enableAudioTrackPlaybackParams ? MAX_PLAYBACK_SPEED : DEFAULT_PLAYBACK_SPEED);
 
     offloadDisabledUntilNextConfiguration = false;
     Configuration pendingConfiguration =