[android] Create MediaCodecBridgeBuilder.java (#3497)

Copied `MediaCodecBridge.createAudioMediaCodecBridge()` to it as is,
without any modifications, except that it's commented out. This makes
further changes more straightforward to review.

Also remove an extra ';' in MediaFormatBuilder.java.

b/345542000

Change-Id: Iabc9af942f27ba126e2b23e2849b9d4103f69957

starboard/android/apk/app/src/main/java/dev/cobalt/media/MediaCodecBridgeBuilder.java

@@ -0,0 +1,78 @@
+// Copyright 2024 The Cobalt Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// Copyright 2018 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package dev.cobalt.media;
+
+/*
+class MediaCodecBridgeBuilder {
+  @SuppressWarnings("unused")
+  @UsedByNative
+  public static MediaCodecBridge createAudioMediaCodecBridge(
+      long nativeMediaCodecBridge,
+      String mime,
+      String decoderName,
+      int sampleRate,
+      int channelCount,
+      MediaCrypto crypto,
+      @Nullable byte[] configurationData) {
+    if (decoderName.equals("")) {
+      Log.e(TAG, "Invalid decoder name.");
+      return null;
+    }
+    MediaCodec mediaCodec = null;
+    try {
+      Log.i(TAG, "Creating \"%s\" decoder.", decoderName);
+      mediaCodec = MediaCodec.createByCodecName(decoderName);
+    } catch (Exception e) {
+      Log.e(TAG, "Failed to create MediaCodec: %s, DecoderName: %s", mime, decoderName, e);
+      return null;
+    }
+    if (mediaCodec == null) {
+      return null;
+    }
+    MediaCodecBridge bridge =
+        new MediaCodecBridge(
+            nativeMediaCodecBridge, mediaCodec, mime, BitrateAdjustmentTypes.NO_ADJUSTMENT, -1);
+
+    MediaFormat mediaFormat = createAudioFormat(mime, sampleRate, channelCount);
+
+    if (mime.contains("opus")) {
+      if (!setOpusConfigurationData(mediaFormat, sampleRate, configurationData)) {
+        bridge.release();
+        return null;
+      }
+    } else {
+      // TODO: Determine if we should explicitly check the mime for AAC audio before calling
+      // setFrameHasADTSHeader(), as more codecs may be supported here in the future.
+      setFrameHasADTSHeader(mediaFormat);
+    }
+    if (!bridge.configureAudio(mediaFormat, crypto, 0)) {
+      Log.e(TAG, "Failed to configure audio codec.");
+      bridge.release();
+      return null;
+    }
+    if (!bridge.start()) {
+      Log.e(TAG, "Failed to start audio codec.");
+      bridge.release();
+      return null;
+    }
+
+    return bridge;
+  }
+}
+*/

starboard/android/apk/app/src/main/java/dev/cobalt/media/MediaFormatBuilder.java

@@ -32,5 +32,46 @@ public static void setCodecSpecificData(MediaFormat format, byte[][] csds) {
       format.setByteBuffer(name, ByteBuffer.wrap(csds[i]));
     }
   }
+
+  /*
+  @SuppressWarnings("unused")
+  private static boolean setOpusConfigurationData(
+      MediaFormat format, int sampleRate, @Nullable byte[] configurationData) {
+    final int MIN_OPUS_INITIALIZATION_DATA_BUFFER_SIZE = 19;
+    final long NANOSECONDS_IN_ONE_SECOND = 1000000000L;
+    // 3840 is the default seek pre-roll samples used by ExoPlayer:
+    // https://github.com/google/ExoPlayer/blob/0ba317b1337eaa789f05dd6c5241246478a3d1e5/library/common/src/main/java/com/google/android/exoplayer2/audio/OpusUtil.java#L30.
+    final int DEFAULT_SEEK_PRE_ROLL_SAMPLES = 3840;
+    if (configurationData == null
+        || configurationData.length < MIN_OPUS_INITIALIZATION_DATA_BUFFER_SIZE) {
+      Log.e(
+          TAG,
+          "Failed to configure Opus audio codec. "
+              + (configurationData == null
+                  ? "|configurationData| is null."
+                  : String.format(
+                      Locale.US,
+                      "Configuration data size (%d) is less than the required size (%d).",
+                      configurationData.length,
+                      MIN_OPUS_INITIALIZATION_DATA_BUFFER_SIZE)));
+      return false;
+    }
+    // Both the number of samples to skip from the beginning of the stream and the amount of time
+    // to pre-roll when seeking must be specified when configuring the Opus decoder. Logic adapted
+    // from ExoPlayer:
+    // https://github.com/google/ExoPlayer/blob/0ba317b1337eaa789f05dd6c5241246478a3d1e5/library/common/src/main/java/com/google/android/exoplayer2/audio/OpusUtil.java#L52.
+    int preSkipSamples = ((configurationData[11] & 0xFF) << 8) | (configurationData[10] & 0xFF);
+    long preSkipNanos = (preSkipSamples * NANOSECONDS_IN_ONE_SECOND) / sampleRate;
+    long seekPreRollNanos =
+        (DEFAULT_SEEK_PRE_ROLL_SAMPLES * NANOSECONDS_IN_ONE_SECOND) / sampleRate;
+    MediaFormatBuilder.setCodecSpecificData(
+        format,
+        new byte[][] {
+          configurationData,
+          ByteBuffer.allocate(8).order(ByteOrder.nativeOrder()).putLong(preSkipNanos).array(),
+          ByteBuffer.allocate(8).order(ByteOrder.nativeOrder()).putLong(seekPreRollNanos).array(),
+        });
+    return true;
+  }
+  */
 }
-;