From ecc703929354d51b5e48854d41e222c51497f5d3 Mon Sep 17 00:00:00 2001 From: "xiaomings@google.com" Date: Mon, 9 Jul 2012 22:57:24 +0000 Subject: Add HE AAC support to ISO BMFF. Also abstract common code in H264BitReader into BitReader for reusing. Was: https://chromiumcodereview.appspot.com/10710002/ In the submitted patch of the last issue, the media.gyp included a non-existing file. This error hadn't been caught by try but later got caught by the build process and reverted the commit. So I create this issue to submit the fixed patch. BUG=134445 TEST=BitReaderTest, AACTest Review URL: https://chromiumcodereview.appspot.com/10753005 git-svn-id: svn://svn.chromium.org/chrome/trunk/src@145769 0039d316-1c4b-4281-b951-d872f2087c98 --- media/mp4/aac.h | 67 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 67 insertions(+) create mode 100644 media/mp4/aac.h (limited to 'media/mp4/aac.h') diff --git a/media/mp4/aac.h b/media/mp4/aac.h new file mode 100644 index 0000000..7a2a3f8 --- /dev/null +++ b/media/mp4/aac.h @@ -0,0 +1,67 @@ +// 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_AAC_H_ +#define MEDIA_MP4_AAC_H_ + +#include + +#include "base/basictypes.h" +#include "media/base/channel_layout.h" +#include "media/base/media_export.h" + +namespace media { + +class BitReader; + +namespace mp4 { + +// This class parses the AAC information from decoder specific information +// embedded in the esds box in an ISO BMFF file. +// Please refer to ISO 14496 Part 3 Table 1.13 - Syntax of AudioSpecificConfig +// for more details. +class MEDIA_EXPORT AAC { + public: + AAC(); + ~AAC(); + + // Parse the AAC config from the raw binary data embedded in esds box. + // The function will parse the data and get the ElementaryStreamDescriptor, + // then it will parse the ElementaryStreamDescriptor to get audio stream + // configurations. + bool Parse(const std::vector& data); + + uint32 frequency() const; + ChannelLayout channel_layout() const; + + // This function converts a raw AAC frame into an AAC frame with an ADTS + // header. On success, the function returns true and stores the converted data + // in the buffer. The function returns false on failure and leaves the buffer + // unchanged. + bool ConvertEsdsToADTS(std::vector* buffer) const; + + private: + bool SkipDecoderGASpecificConfig(BitReader* bit_reader) const; + bool SkipErrorSpecificConfig() const; + bool SkipGASpecificConfig(BitReader* bit_reader) const; + + // The following variables store the AAC specific configuration information + // that are used to generate the ADTS header. + uint8 profile_; + uint8 frequency_index_; + uint8 channel_config_; + + // The following variables store audio configuration information that + // can be used by Chromium. They are based on the AAC specific + // configuration but can be overridden by extensions in elementary + // stream descriptor. + uint32 frequency_; + ChannelLayout channel_layout_; +}; + +} // namespace mp4 + +} // namespace media + +#endif // MEDIA_MP4_AAC_H_ -- cgit v1.1