Add HE AAC support to ISO BMFF.

1. Parse esds box to get HE AAC config.
2. Send audio config from AAC header to decoder instead of the one embedded in SampleDescription.
3. Convert raw audio data into ADTS before sending to decoder.
4. Abstract general bit stream code from H264BitReader into media::BitReader.

BUG=134445
TEST=BitReaderTest, AACTest


Review URL: https://chromiumcodereview.appspot.com/10710002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@145617 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 57 insertions, 0 deletions

diff --git a/media/mp4/es_descriptor.h b/media/mp4/es_descriptor.h
new file mode 100644
index 0000000..daddbc0
--- /dev/null
+++ b/media/mp4/es_descriptor.h
@@ -0,0 +1,57 @@
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef MEDIA_MP4_ES_DESCRIPTOR_H_
+#define MEDIA_MP4_ES_DESCRIPTOR_H_
+
+#include <vector>
+
+#include "base/basictypes.h"
+#include "media/base/media_export.h"
+
+namespace media {
+
+class BitReader;
+
+namespace mp4 {
+
+// The following values are extracted from ISO 14496 Part 1 Table 5 -
+// objectTypeIndication Values. Only values currently in use are included.
+enum ObjectType {
+  kForbidden = 0,
+  kISO_14496_3 = 0x40  // MPEG4 AAC
+};
+
+// This class parse object type and decoder specific information from an
+// elementary stream descriptor, which is usually contained in an esds box.
+// Please refer to ISO 14496 Part 1 7.2.6.5 for more details.
+class MEDIA_EXPORT ESDescriptor {
+ public:
+  ESDescriptor();
+  ~ESDescriptor();
+
+  bool Parse(const std::vector<uint8>& data);
+
+  uint8 object_type() const;
+  const std::vector<uint8>& decoder_specific_info() const;
+
+ private:
+  enum Tag {
+    kESDescrTag = 0x03,
+    kDecoderConfigDescrTag = 0x04,
+    kDecoderSpecificInfoTag = 0x05
+  };
+
+  bool ParseDecoderConfigDescriptor(BitReader* reader);
+  bool ParseDecoderSpecificInfo(BitReader* reader);
+
+  uint8 object_type_;
+  std::vector<uint8> decoder_specific_info_;
+};
+
+}  // namespace mp4
+
+}  // namespace media
+
+#endif  // MEDIA_MP4_ES_DESCRIPTOR_H_