1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/content/media/directshow/DirectShowReader.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,119 @@
1.4 +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
1.5 +/* vim:set ts=2 sw=2 sts=2 et cindent: */
1.6 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.7 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.8 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.9 +
1.10 +#if !defined(DirectShowReader_h_)
1.11 +#define DirectShowReader_h_
1.12 +
1.13 +#include "windows.h" // HRESULT, DWORD
1.14 +#include "MediaDecoderReader.h"
1.15 +#include "mozilla/RefPtr.h"
1.16 +#include "MP3FrameParser.h"
1.17 +
1.18 +class IGraphBuilder;
1.19 +class IMediaControl;
1.20 +class IMediaSeeking;
1.21 +class IMediaEventEx;
1.22 +
1.23 +namespace mozilla {
1.24 +
1.25 +class AudioSinkFilter;
1.26 +class SourceFilter;
1.27 +
1.28 +namespace dom {
1.29 +class TimeRanges;
1.30 +}
1.31 +
1.32 +// Decoder backend for decoding MP3 using DirectShow. DirectShow operates as
1.33 +// a filter graph. The basic design of the DirectShowReader is that we have
1.34 +// a SourceFilter that wraps the MediaResource that connects to the
1.35 +// MP3 decoder filter. The MP3 decoder filter "pulls" data as it requires it
1.36 +// downstream on its own thread. When the MP3 decoder has produced a block of
1.37 +// decoded samples, its thread calls downstream into our AudioSinkFilter,
1.38 +// passing the decoded buffer in. The AudioSinkFilter inserts the samples into
1.39 +// a SampleSink object. The SampleSink blocks the MP3 decoder's thread until
1.40 +// the decode thread calls DecodeAudioData(), whereupon the SampleSink
1.41 +// releases the decoded samples to the decode thread, and unblocks the MP3
1.42 +// decoder's thread. The MP3 decoder can then request more data from the
1.43 +// SourceFilter, and decode more data. If the decode thread calls
1.44 +// DecodeAudioData() and there's no decoded samples waiting to be extracted
1.45 +// in the SampleSink, the SampleSink blocks the decode thread until the MP3
1.46 +// decoder produces a decoded sample.
1.47 +class DirectShowReader : public MediaDecoderReader
1.48 +{
1.49 +public:
1.50 + DirectShowReader(AbstractMediaDecoder* aDecoder);
1.51 +
1.52 + virtual ~DirectShowReader();
1.53 +
1.54 + nsresult Init(MediaDecoderReader* aCloneDonor) MOZ_OVERRIDE;
1.55 +
1.56 + bool DecodeAudioData() MOZ_OVERRIDE;
1.57 + bool DecodeVideoFrame(bool &aKeyframeSkip,
1.58 + int64_t aTimeThreshold) MOZ_OVERRIDE;
1.59 +
1.60 + bool HasAudio() MOZ_OVERRIDE;
1.61 + bool HasVideo() MOZ_OVERRIDE;
1.62 +
1.63 + nsresult ReadMetadata(MediaInfo* aInfo,
1.64 + MetadataTags** aTags) MOZ_OVERRIDE;
1.65 +
1.66 + nsresult Seek(int64_t aTime,
1.67 + int64_t aStartTime,
1.68 + int64_t aEndTime,
1.69 + int64_t aCurrentTime) MOZ_OVERRIDE;
1.70 +
1.71 + void NotifyDataArrived(const char* aBuffer,
1.72 + uint32_t aLength,
1.73 + int64_t aOffset) MOZ_OVERRIDE;
1.74 +
1.75 +private:
1.76 +
1.77 + // Notifies the filter graph that playback is complete. aStatus is
1.78 + // the code to send to the filter graph. Always returns false, so
1.79 + // that we can just "return Finish()" from DecodeAudioData().
1.80 + bool Finish(HRESULT aStatus);
1.81 +
1.82 + // DirectShow filter graph, and associated playback and seeking
1.83 + // control interfaces.
1.84 + RefPtr<IGraphBuilder> mGraph;
1.85 + RefPtr<IMediaControl> mControl;
1.86 + RefPtr<IMediaSeeking> mMediaSeeking;
1.87 +
1.88 + // Wraps the MediaResource, and feeds undecoded data into the filter graph.
1.89 + RefPtr<SourceFilter> mSourceFilter;
1.90 +
1.91 + // Sits at the end of the graph, removing decoded samples from the graph.
1.92 + // The graph will block while this is blocked, i.e. it will pause decoding.
1.93 + RefPtr<AudioSinkFilter> mAudioSinkFilter;
1.94 +
1.95 + // Some MP3s are variable bitrate, so DirectShow's duration estimation
1.96 + // can make its duration estimation based on the wrong bitrate. So we parse
1.97 + // the MP3 frames to get a more accuate estimate of the duration.
1.98 + MP3FrameParser mMP3FrameParser;
1.99 +
1.100 +#ifdef DEBUG
1.101 + // Used to add/remove the filter graph to the Running Object Table. You can
1.102 + // connect GraphEdit/GraphStudio to the graph to observe and/or debug its
1.103 + // topology and state.
1.104 + DWORD mRotRegister;
1.105 +#endif
1.106 +
1.107 + // Number of channels in the audio stream.
1.108 + uint32_t mNumChannels;
1.109 +
1.110 + // Samples per second in the audio stream.
1.111 + uint32_t mAudioRate;
1.112 +
1.113 + // Number of bytes per sample. Can be either 1 or 2.
1.114 + uint32_t mBytesPerSample;
1.115 +
1.116 + // Duration of the stream, in microseconds.
1.117 + int64_t mDuration;
1.118 +};
1.119 +
1.120 +} // namespace mozilla
1.121 +
1.122 +#endif
