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Diffstat (limited to 'chromium/media/formats/mpeg/mpeg_audio_stream_parser_base.h')
| -rw-r--r-- | chromium/media/formats/mpeg/mpeg_audio_stream_parser_base.h | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/chromium/media/formats/mpeg/mpeg_audio_stream_parser_base.h b/chromium/media/formats/mpeg/mpeg_audio_stream_parser_base.h new file mode 100644 index 00000000000..31a1b7c3837 --- /dev/null +++ b/chromium/media/formats/mpeg/mpeg_audio_stream_parser_base.h @@ -0,0 +1,156 @@ +// Copyright 2014 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_FORMATS_MPEG_MPEG_AUDIO_STREAM_PARSER_BASE_H_ +#define MEDIA_FORMATS_MPEG_MPEG_AUDIO_STREAM_PARSER_BASE_H_ + +#include <set> +#include <vector> + +#include "base/basictypes.h" +#include "base/callback.h" +#include "media/base/audio_decoder_config.h" +#include "media/base/audio_timestamp_helper.h" +#include "media/base/bit_reader.h" +#include "media/base/byte_queue.h" +#include "media/base/media_export.h" +#include "media/base/stream_parser.h" + +namespace media { + +class MEDIA_EXPORT MPEGAudioStreamParserBase : public StreamParser { + public: + // |start_code_mask| is used to find the start of each frame header. Also + // referred to as the sync code in the MP3 and ADTS header specifications. + // |codec_delay| is the number of samples the decoder will output before the + // first real frame. + MPEGAudioStreamParserBase(uint32 start_code_mask, + AudioCodec audio_codec, + int codec_delay); + virtual ~MPEGAudioStreamParserBase(); + + // StreamParser implementation. + virtual void Init(const InitCB& init_cb, + const NewConfigCB& config_cb, + const NewBuffersCB& new_buffers_cb, + bool ignore_text_tracks, + const NeedKeyCB& need_key_cb, + const NewMediaSegmentCB& new_segment_cb, + const base::Closure& end_of_segment_cb, + const LogCB& log_cb) OVERRIDE; + virtual void Flush() OVERRIDE; + virtual bool Parse(const uint8* buf, int size) OVERRIDE; + + protected: + // Subclasses implement this method to parse format specific frame headers. + // |data| & |size| describe the data available for parsing. + // + // Implementations are expected to consume an entire frame header. It should + // only return a value greater than 0 when |data| has enough bytes to + // successfully parse & consume the entire frame header. + // + // |frame_size| - Required parameter that is set to the size of the frame, in + // bytes, including the frame header if the function returns a value > 0. + // |sample_rate| - Optional parameter that is set to the sample rate + // of the frame if this function returns a value > 0. + // |channel_layout| - Optional parameter that is set to the channel_layout + // of the frame if this function returns a value > 0. + // |sample_count| - Optional parameter that is set to the number of samples + // in the frame if this function returns a value > 0. + // |metadata_frame| - Optional parameter that is set to true if the frame has + // valid values for the above parameters, but no usable encoded data; only set + // to true if this function returns a value > 0. + // + // |sample_rate|, |channel_layout|, |sample_count|, |metadata_frame| may be + // NULL if the caller is not interested in receiving these values from the + // frame header. + // + // If |metadata_frame| is true, the MPEGAudioStreamParserBase will discard the + // frame after consuming the metadata values above. + // + // Returns: + // > 0 : The number of bytes parsed. + // 0 : If more data is needed to parse the entire frame header. + // < 0 : An error was encountered during parsing. + virtual int ParseFrameHeader(const uint8* data, + int size, + int* frame_size, + int* sample_rate, + ChannelLayout* channel_layout, + int* sample_count, + bool* metadata_frame) const = 0; + + const LogCB& log_cb() const { return log_cb_; } + + private: + enum State { + UNINITIALIZED, + INITIALIZED, + PARSE_ERROR + }; + + void ChangeState(State state); + + // Parsing functions for various byte stream elements. |data| & |size| + // describe the data available for parsing. + // + // Returns: + // > 0 : The number of bytes parsed. + // 0 : If more data is needed to parse the entire element. + // < 0 : An error was encountered during parsing. + int ParseFrame(const uint8* data, int size, BufferQueue* buffers); + int ParseIcecastHeader(const uint8* data, int size); + int ParseID3v1(const uint8* data, int size); + int ParseID3v2(const uint8* data, int size); + + // Parses an ID3v2 "sync safe" integer. + // |reader| - A BitReader to read from. + // |value| - Set to the integer value read, if true is returned. + // + // Returns true if the integer was successfully parsed and |value| + // was set. + // Returns false if an error was encountered. The state of |value| is + // undefined when false is returned. + bool ParseSyncSafeInt(BitReader* reader, int32* value); + + // Scans |data| for the next valid start code. + // Returns: + // > 0 : The number of bytes that should be skipped to reach the + // next start code.. + // 0 : If a valid start code was not found and more data is needed. + // < 0 : An error was encountered during parsing. + int FindNextValidStartCode(const uint8* data, int size) const; + + // Sends the buffers in |buffers| to |new_buffers_cb_| and then clears + // |buffers|. + // If |end_of_segment| is set to true, then |end_of_segment_cb_| is called + // after |new_buffers_cb_| to signal that these buffers represent the end of a + // media segment. + // Returns true if the buffers are sent successfully. + bool SendBuffers(BufferQueue* buffers, bool end_of_segment); + + State state_; + + InitCB init_cb_; + NewConfigCB config_cb_; + NewBuffersCB new_buffers_cb_; + NewMediaSegmentCB new_segment_cb_; + base::Closure end_of_segment_cb_; + LogCB log_cb_; + + ByteQueue queue_; + + AudioDecoderConfig config_; + scoped_ptr<AudioTimestampHelper> timestamp_helper_; + bool in_media_segment_; + const uint32 start_code_mask_; + const AudioCodec audio_codec_; + const int codec_delay_; + + DISALLOW_COPY_AND_ASSIGN(MPEGAudioStreamParserBase); +}; + +} // namespace media + +#endif // MEDIA_FORMATS_MPEG_MPEG_AUDIO_STREAM_PARSER_BASE_H_ |