content/media/directshow/DirectShowReader.h@b8a032363ba2 (annotated)
content/media/directshow/DirectShowReader.h
Thu, 22 Jan 2015 13:21:57 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Thu, 22 Jan 2015 13:21:57 +0100
- branch
- TOR_BUG_9701
- changeset 15
- b8a032363ba2
- permissions
- -rw-r--r--
Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6
| michael@0 | 1 | /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ |
| michael@0 | 2 | /* vim:set ts=2 sw=2 sts=2 et cindent: */ |
| michael@0 | 3 | /* This Source Code Form is subject to the terms of the Mozilla Public |
| michael@0 | 4 | * License, v. 2.0. If a copy of the MPL was not distributed with this |
| michael@0 | 5 | * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ |
| michael@0 | 6 | |
| michael@0 | 7 | #if !defined(DirectShowReader_h_) |
| michael@0 | 8 | #define DirectShowReader_h_ |
| michael@0 | 9 | |
| michael@0 | 10 | #include "windows.h" // HRESULT, DWORD |
| michael@0 | 11 | #include "MediaDecoderReader.h" |
| michael@0 | 12 | #include "mozilla/RefPtr.h" |
| michael@0 | 13 | #include "MP3FrameParser.h" |
| michael@0 | 14 | |
| michael@0 | 15 | class IGraphBuilder; |
| michael@0 | 16 | class IMediaControl; |
| michael@0 | 17 | class IMediaSeeking; |
| michael@0 | 18 | class IMediaEventEx; |
| michael@0 | 19 | |
| michael@0 | 20 | namespace mozilla { |
| michael@0 | 21 | |
| michael@0 | 22 | class AudioSinkFilter; |
| michael@0 | 23 | class SourceFilter; |
| michael@0 | 24 | |
| michael@0 | 25 | namespace dom { |
| michael@0 | 26 | class TimeRanges; |
| michael@0 | 27 | } |
| michael@0 | 28 | |
| michael@0 | 29 | // Decoder backend for decoding MP3 using DirectShow. DirectShow operates as |
| michael@0 | 30 | // a filter graph. The basic design of the DirectShowReader is that we have |
| michael@0 | 31 | // a SourceFilter that wraps the MediaResource that connects to the |
| michael@0 | 32 | // MP3 decoder filter. The MP3 decoder filter "pulls" data as it requires it |
| michael@0 | 33 | // downstream on its own thread. When the MP3 decoder has produced a block of |
| michael@0 | 34 | // decoded samples, its thread calls downstream into our AudioSinkFilter, |
| michael@0 | 35 | // passing the decoded buffer in. The AudioSinkFilter inserts the samples into |
| michael@0 | 36 | // a SampleSink object. The SampleSink blocks the MP3 decoder's thread until |
| michael@0 | 37 | // the decode thread calls DecodeAudioData(), whereupon the SampleSink |
| michael@0 | 38 | // releases the decoded samples to the decode thread, and unblocks the MP3 |
| michael@0 | 39 | // decoder's thread. The MP3 decoder can then request more data from the |
| michael@0 | 40 | // SourceFilter, and decode more data. If the decode thread calls |
| michael@0 | 41 | // DecodeAudioData() and there's no decoded samples waiting to be extracted |
| michael@0 | 42 | // in the SampleSink, the SampleSink blocks the decode thread until the MP3 |
| michael@0 | 43 | // decoder produces a decoded sample. |
| michael@0 | 44 | class DirectShowReader : public MediaDecoderReader |
| michael@0 | 45 | { |
| michael@0 | 46 | public: |
| michael@0 | 47 | DirectShowReader(AbstractMediaDecoder* aDecoder); |
| michael@0 | 48 | |
| michael@0 | 49 | virtual ~DirectShowReader(); |
| michael@0 | 50 | |
| michael@0 | 51 | nsresult Init(MediaDecoderReader* aCloneDonor) MOZ_OVERRIDE; |
| michael@0 | 52 | |
| michael@0 | 53 | bool DecodeAudioData() MOZ_OVERRIDE; |
| michael@0 | 54 | bool DecodeVideoFrame(bool &aKeyframeSkip, |
| michael@0 | 55 | int64_t aTimeThreshold) MOZ_OVERRIDE; |
| michael@0 | 56 | |
| michael@0 | 57 | bool HasAudio() MOZ_OVERRIDE; |
| michael@0 | 58 | bool HasVideo() MOZ_OVERRIDE; |
| michael@0 | 59 | |
| michael@0 | 60 | nsresult ReadMetadata(MediaInfo* aInfo, |
| michael@0 | 61 | MetadataTags** aTags) MOZ_OVERRIDE; |
| michael@0 | 62 | |
| michael@0 | 63 | nsresult Seek(int64_t aTime, |
| michael@0 | 64 | int64_t aStartTime, |
| michael@0 | 65 | int64_t aEndTime, |
| michael@0 | 66 | int64_t aCurrentTime) MOZ_OVERRIDE; |
| michael@0 | 67 | |
| michael@0 | 68 | void NotifyDataArrived(const char* aBuffer, |
| michael@0 | 69 | uint32_t aLength, |
| michael@0 | 70 | int64_t aOffset) MOZ_OVERRIDE; |
| michael@0 | 71 | |
| michael@0 | 72 | private: |
| michael@0 | 73 | |
| michael@0 | 74 | // Notifies the filter graph that playback is complete. aStatus is |
| michael@0 | 75 | // the code to send to the filter graph. Always returns false, so |
| michael@0 | 76 | // that we can just "return Finish()" from DecodeAudioData(). |
| michael@0 | 77 | bool Finish(HRESULT aStatus); |
| michael@0 | 78 | |
| michael@0 | 79 | // DirectShow filter graph, and associated playback and seeking |
| michael@0 | 80 | // control interfaces. |
| michael@0 | 81 | RefPtr<IGraphBuilder> mGraph; |
| michael@0 | 82 | RefPtr<IMediaControl> mControl; |
| michael@0 | 83 | RefPtr<IMediaSeeking> mMediaSeeking; |
| michael@0 | 84 | |
| michael@0 | 85 | // Wraps the MediaResource, and feeds undecoded data into the filter graph. |
| michael@0 | 86 | RefPtr<SourceFilter> mSourceFilter; |
| michael@0 | 87 | |
| michael@0 | 88 | // Sits at the end of the graph, removing decoded samples from the graph. |
| michael@0 | 89 | // The graph will block while this is blocked, i.e. it will pause decoding. |
| michael@0 | 90 | RefPtr<AudioSinkFilter> mAudioSinkFilter; |
| michael@0 | 91 | |
| michael@0 | 92 | // Some MP3s are variable bitrate, so DirectShow's duration estimation |
| michael@0 | 93 | // can make its duration estimation based on the wrong bitrate. So we parse |
| michael@0 | 94 | // the MP3 frames to get a more accuate estimate of the duration. |
| michael@0 | 95 | MP3FrameParser mMP3FrameParser; |
| michael@0 | 96 | |
| michael@0 | 97 | #ifdef DEBUG |
| michael@0 | 98 | // Used to add/remove the filter graph to the Running Object Table. You can |
| michael@0 | 99 | // connect GraphEdit/GraphStudio to the graph to observe and/or debug its |
| michael@0 | 100 | // topology and state. |
| michael@0 | 101 | DWORD mRotRegister; |
| michael@0 | 102 | #endif |
| michael@0 | 103 | |
| michael@0 | 104 | // Number of channels in the audio stream. |
| michael@0 | 105 | uint32_t mNumChannels; |
| michael@0 | 106 | |
| michael@0 | 107 | // Samples per second in the audio stream. |
| michael@0 | 108 | uint32_t mAudioRate; |
| michael@0 | 109 | |
| michael@0 | 110 | // Number of bytes per sample. Can be either 1 or 2. |
| michael@0 | 111 | uint32_t mBytesPerSample; |
| michael@0 | 112 | |
| michael@0 | 113 | // Duration of the stream, in microseconds. |
| michael@0 | 114 | int64_t mDuration; |
| michael@0 | 115 | }; |
| michael@0 | 116 | |
| michael@0 | 117 | } // namespace mozilla |
| michael@0 | 118 | |
| michael@0 | 119 | #endif |
