Use passthrough decoder for (E)AC3 formats

media/base/ac3_util.h

Index: media/base/ac3_util.h
diff --git a/media/base/ac3_util.h b/media/base/ac3_util.h
new file mode 100644
index 0000000000000000000000000000000000000000..95874bf8701bd59e64bb6f7f38fd290804961804
--- /dev/null
+++ b/media/base/ac3_util.h
@@ -0,0 +1,31 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.

[DaleCurtis, 2016/12/14 20:00:03]

Should go in media/formats/ probably.

[AndyWu, 2016/12/15 22:20:03]

Done.

+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef MEDIA_BASE_AC3_UTIL_H_
+#define MEDIA_BASE_AC3_UTIL_H_
+
+#include <stddef.h>
+#include <stdint.h>
+
+#include "base/macros.h"
+
+namespace media {
+
+class Ac3Util {
+ public:
+  // Returns the total number of audio samples in the given buffer, which
+  // contains several complete AC3 syncframes.
+  static int ParseTotalAc3SampleCount(const uint8_t* data, size_t size);
+
+  // Returns the total number of audio samples in the given buffer, which
+  // contains several complete E-AC3 syncframes.
+  static int ParseTotalEac3SampleCount(const uint8_t* data, size_t size);
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(Ac3Util);
+};
+
+}  // namespace media
+
+#endif  // MEDIA_BASE_AC3_UTIL_H_