| // Copyright 2015 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_FILTERS_LIBWEBM_MUXER_H_ |
| #define MEDIA_FILTERS_LIBWEBM_MUXER_H_ |
| |
| #include "base/callback.h" |
| #include "base/numerics/safe_math.h" |
| #include "base/strings/string_piece.h" |
| #include "base/threading/thread_checker.h" |
| #include "base/time/time.h" |
| #include "media/base/media_export.h" |
| #include "media/base/video_codecs.h" |
| #include "third_party/libwebm/source/mkvmuxer.hpp" |
| |
| namespace gfx { |
| class Size; |
| } // namespace gfx |
| |
| namespace media { |
| |
| class VideoFrame; |
| |
| // Adapter class to manage a WebM container [1], a simplified version of a |
| // Matroska container [2], composed of an EBML header, and a single Segment |
| // including at least a Track Section and a number of SimpleBlocks each |
| // containing a single encoded video frame. WebM container has no Trailer. |
| // Clients will push encoded VPx video frames one by one via OnEncodedVideo(). |
| // libwebm will eventually ping the WriteDataCB passed on contructor with the |
| // wrapped encoded data. |
| // WebmMuxer is designed for single thread use throughout. |
| // [1] http://www.webmproject.org/docs/container/ |
| // [2] http://www.matroska.org/technical/specs/index.html |
| // TODO(mcasas): Add support for Audio muxing. |
| class MEDIA_EXPORT WebmMuxer : public NON_EXPORTED_BASE(mkvmuxer::IMkvWriter) { |
| public: |
| // Callback to be called when WebmMuxer is ready to write a chunk of data, |
| // either any file header or a SingleBlock. |
| using WriteDataCB = base::Callback<void(base::StringPiece)>; |
| |
| // |codec| can be VP8 or VP9 and should coincide with whatever is sent in |
| // OnEncodedVideo(). |
| WebmMuxer(VideoCodec codec, const WriteDataCB& write_data_callback); |
| ~WebmMuxer() override; |
| |
| // Adds a |video_frame| with |encoded_data.data()| to WebM Segment. |
| void OnEncodedVideo(const scoped_refptr<VideoFrame>& video_frame, |
| scoped_ptr<std::string> encoded_data, |
| base::TimeTicks timestamp, |
| bool is_key_frame); |
| |
| private: |
| friend class WebmMuxerTest; |
| |
| // Creates and adds a new video track. Called upon receiving the first |
| // frame of a given Track, adds |frame_size| and |frame_rate| to the Segment |
| // info, although individual frames passed to OnEncodedVideo() can have any |
| // frame size. |
| void AddVideoTrack(const gfx::Size& frame_size, double frame_rate); |
| |
| // IMkvWriter interface. |
| mkvmuxer::int32 Write(const void* buf, mkvmuxer::uint32 len) override; |
| mkvmuxer::int64 Position() const override; |
| mkvmuxer::int32 Position(mkvmuxer::int64 position) override; |
| bool Seekable() const override; |
| void ElementStartNotify(mkvmuxer::uint64 element_id, |
| mkvmuxer::int64 position) override; |
| |
| // Used to DCHECK that we are called on the correct thread. |
| base::ThreadChecker thread_checker_; |
| |
| // Video Codec configured: VP9 if true, otherwise VP8 is used by default. |
| const bool use_vp9_; |
| |
| // A caller-side identifier to interact with |segment_|, initialised upon |
| // first frame arrival by AddVideoTrack(). |
| uint64_t track_index_; |
| |
| // Origin of times for frame timestamps. |
| base::TimeTicks first_frame_timestamp_; |
| |
| // Callback to dump written data as being called by libwebm. |
| const WriteDataCB write_data_callback_; |
| |
| // Rolling counter of the position in bytes of the written goo. |
| base::CheckedNumeric<mkvmuxer::int64> position_; |
| |
| // The MkvMuxer active element. |
| mkvmuxer::Segment segment_; |
| |
| DISALLOW_COPY_AND_ASSIGN(WebmMuxer); |
| }; |
| |
| } // namespace media |
| |
| #endif // MEDIA_FILTERS_LIBWEBM_MUXER_H_ |