diff options
Diffstat (limited to 'media/base/pipeline_impl.h')
| -rw-r--r-- | media/base/pipeline_impl.h | 277 |
1 files changed, 101 insertions, 176 deletions
diff --git a/media/base/pipeline_impl.h b/media/base/pipeline_impl.h index b72e368..1050ef1 100644 --- a/media/base/pipeline_impl.h +++ b/media/base/pipeline_impl.h @@ -20,16 +20,28 @@ namespace media { -class PipelineInternal; - -// Class which implements the Media::Pipeline contract. The majority of the -// actual code for this object lives in the PipelineInternal class, which is -// responsible for actually building and running the pipeline. This object -// is basically a simple container for state information, and is responsible -// for creating and communicating with the PipelineInternal object. -class PipelineImpl : public Pipeline { + +// PipelineImpl runs the media pipeline. Filters are created and called on the +// message loop injected into this object. PipelineImpl works like a state +// machine to perform asynchronous initialization. Initialization is done in +// multiple passes by InitializeTask(). In each pass a different filter is +// created and chained with a previously created filter. +// +// Here's a state diagram that describes the lifetime of this object. +// +// [ *Created ] -> [ InitDataSource ] -> [ InitDemuxer ] -> +// [ InitAudioDecoder ] -> [ InitAudioRenderer ] -> +// [ InitVideoDecoder ] -> [ InitVideoRenderer ] -> [ Started ] +// | | | +// .-> [ Error ] .-> [ Stopped ] <-. +// +// Initialization is a series of state transitions from "Created" to +// "Started". If any error happens during initialization, this object will +// transition to the "Error" state from any state. If Stop() is called during +// initialization, this object will transition to "Stopped" state. +class PipelineImpl : public Pipeline, public FilterHost { public: - PipelineImpl(MessageLoop* message_loop); + explicit PipelineImpl(MessageLoop* message_loop); // Pipeline implementation. virtual bool Start(FilterFactory* filter_factory, @@ -53,142 +65,17 @@ class PipelineImpl : public Pipeline { virtual PipelineError GetError() const; private: - friend class PipelineInternal; virtual ~PipelineImpl(); // Reset the state of the pipeline object to the initial state. This method - // is used by the constructor, and the Stop method. + // is used by the constructor, and the Stop() method. void ResetState(); - // Used internally to make sure that the thread is in a state that is - // acceptable to post a task to. It must exist, be initialized, and there - // must not be an error. - bool IsPipelineOk() const; - - // Methods called by |pipeline_internal_| to update global pipeline data. - // - // Although this is the exact same as the FilterHost interface, we need to - // let |pipeline_internal_| receive the call first so it can post tasks as - // necessary. - void SetError(PipelineError error); - base::TimeDelta GetTime() const; - void SetTime(base::TimeDelta time); - void SetDuration(base::TimeDelta duration); - void SetBufferedTime(base::TimeDelta buffered_time); - void SetTotalBytes(int64 total_bytes); - void SetBufferedBytes(int64 buffered_bytes); - void SetVideoSize(size_t width, size_t height); - - // Method called by the |pipeline_internal_| to insert a mime type into - // the |rendered_mime_types_| set. - void InsertRenderedMimeType(const std::string& major_mime_type); - - // Message loop used to execute pipeline tasks. - MessageLoop* message_loop_; - - // Holds a ref counted reference to the PipelineInternal object associated - // with this pipeline. Prior to the call to the Start() method, this member - // will be NULL, since we are not running. - scoped_refptr<PipelineInternal> pipeline_internal_; - - // After calling Start, if all of the required filters are created and - // initialized, this member will be set to true by the pipeline thread. - bool initialized_; - - // Duration of the media in microseconds. Set by filters. - base::TimeDelta duration_; - - // Amount of available buffered data in microseconds. Set by filters. - base::TimeDelta buffered_time_; - - // Amount of available buffered data. Set by filters. - int64 buffered_bytes_; - - // Total size of the media. Set by filters. - int64 total_bytes_; - - // Lock used to serialize access for getter/setter methods. - mutable Lock lock_; - - // Video width and height. Set by filters. - size_t video_width_; - size_t video_height_; - - // Current volume level (from 0.0f to 1.0f). This value is set immediately - // via SetVolume() and a task is dispatched on the message loop to notify the - // filters. - float volume_; - - // Current playback rate (>= 0.0f). This value is set immediately via - // SetPlaybackRate() and a task is dispatched on the message loop to notify - // the filters. - float playback_rate_; - - // Current playback time. Set by filters. - base::TimeDelta time_; - - // Status of the pipeline. Initialized to PIPELINE_OK which indicates that - // the pipeline is operating correctly. Any other value indicates that the - // pipeline is stopped or is stopping. Clients can call the Stop method to - // reset the pipeline state, and restore this to PIPELINE_OK. - PipelineError error_; - - // Vector of major mime types that have been rendered by this pipeline. - typedef std::set<std::string> RenderedMimeTypesSet; - RenderedMimeTypesSet rendered_mime_types_; - - DISALLOW_COPY_AND_ASSIGN(PipelineImpl); -}; - - -// PipelineInternal contains most of the logic involved with running the -// media pipeline. Filters are created and called on the message loop injected -// into this object. PipelineInternal works like a state machine to perform -// asynchronous initialization. Initialization is done in multiple passes by -// InitializeTask(). In each pass a different filter is created and chained with -// a previously created filter. -// -// Here's a state diagram that describes the lifetime of this object. -// -// [ *Created ] -> [ InitDataSource ] -> [ InitDemuxer ] -> -// [ InitAudioDecoder ] -> [ InitAudioRenderer ] -> -// [ InitVideoDecoder ] -> [ InitVideoRenderer ] -> [ Started ] -// | | | -// .-> [ Error ] .-> [ Stopped ] <-. -// -// Initialization is a series of state transitions from "Created" to -// "Started". If any error happens during initialization, this object will -// transition to the "Error" state from any state. If Stop() is called during -// initialization, this object will transition to "Stopped" state. - -class PipelineInternal : public FilterHost, - public base::RefCountedThreadSafe<PipelineInternal> { - public: - // Methods called by PipelineImpl object on the client's thread. These - // methods post a task to call a corresponding xxxTask() method on the - // message loop. For example, Seek posts a task to call SeekTask. - PipelineInternal(PipelineImpl* pipeline, MessageLoop* message_loop); - - // After Start() is called, a task of StartTask() is posted on the pipeline - // thread to perform initialization. See StartTask() to learn more about - // initialization. - void Start(FilterFactory* filter_factory, - const std::string& url_media_source, - PipelineCallback* start_callback); - void Stop(PipelineCallback* stop_callback); - void Seek(base::TimeDelta time, PipelineCallback* seek_callback); - - // Notifies that the client has changed the playback rate/volume. - void PlaybackRateChanged(float playback_rate); - void VolumeChanged(float volume); - - // Returns true if the pipeline has fully initialized. - bool IsInitialized() { return state_ == kStarted; } + // Simple method used to make sure the pipeline is running normally. + bool IsPipelineOk(); - private: - // Only allow ourselves to be destroyed via ref-counting. - friend class base::RefCountedThreadSafe<PipelineInternal>; - virtual ~PipelineInternal(); + // Helper method to tell whether we are in the state of initializing. + bool IsPipelineInitializing(); // FilterHost implementation. virtual void SetError(PipelineError error); @@ -200,31 +87,12 @@ class PipelineInternal : public FilterHost, virtual void SetBufferedBytes(int64 buffered_bytes); virtual void SetVideoSize(size_t width, size_t height); - enum State { - kCreated, - kInitDataSource, - kInitDemuxer, - kInitAudioDecoder, - kInitAudioRenderer, - kInitVideoDecoder, - kInitVideoRenderer, - kStarted, - kStopped, - kError, - }; - - // Simple method used to make sure the pipeline is running normally. - bool IsPipelineOk() { return PIPELINE_OK == pipeline_->error_; } + // Method called during initialization to insert a mime type into the + // |rendered_mime_types_| set. + void InsertRenderedMimeType(const std::string& major_mime_type); - // Helper method to tell whether we are in the state of initializing. - bool IsPipelineInitializing() { - return state_ == kInitDataSource || - state_ == kInitDemuxer || - state_ == kInitAudioDecoder || - state_ == kInitAudioRenderer || - state_ == kInitVideoDecoder || - state_ == kInitVideoRenderer; - } + // Method called during initialization to determine if we rendered anything. + bool HasRenderedMimeTypes() const; // Callback executed by filters upon completing initialization and seeking. void OnFilterInitialize(); @@ -243,18 +111,18 @@ class PipelineInternal : public FilterHost, // initialization. void InitializeTask(); - // StopTask() and ErrorTask() are similar but serve different purposes: - // - Both destroy the filter chain. - // - Both will execute |start_callback| if the pipeline was initializing. - // - StopTask() resets the pipeline to a fresh state, where as ErrorTask() - // leaves the pipeline as is for client inspection. - // - StopTask() can be scheduled by the client calling Stop(), where as - // ErrorTask() is scheduled as a result of a filter calling SetError(). + // Stops and destroys all filters, placing the pipeline in the kStopped state + // and setting the error code to PIPELINE_STOPPED. void StopTask(PipelineCallback* stop_callback); - void ErrorTask(PipelineError error); - // Carries out notifying filters that the playback rate/volume has changed, + // Carries out stopping and destroying all filters, placing the pipeline in + // the kError state. + void ErrorChangedTask(PipelineError error); + + // Carries out notifying filters that the playback rate has changed. void PlaybackRateChangedTask(float playback_rate); + + // Carries out notifying filters that the volume has changed. void VolumeChangedTask(float volume); // Carries out notifying filters that we are seeking to a new timestamp. @@ -326,13 +194,70 @@ class PipelineInternal : public FilterHost, // references to them. void DestroyFilters(); - // Pointer to the pipeline that owns this PipelineInternal. - PipelineImpl* pipeline_; - // Message loop used to execute pipeline tasks. MessageLoop* message_loop_; + // Lock used to serialize access for the following data members. + mutable Lock lock_; + + // Whether or not the pipeline is running. + bool running_; + + // Duration of the media in microseconds. Set by filters. + base::TimeDelta duration_; + + // Amount of available buffered data in microseconds. Set by filters. + base::TimeDelta buffered_time_; + + // Amount of available buffered data. Set by filters. + int64 buffered_bytes_; + + // Total size of the media. Set by filters. + int64 total_bytes_; + + // Video width and height. Set by filters. + size_t video_width_; + size_t video_height_; + + // Current volume level (from 0.0f to 1.0f). This value is set immediately + // via SetVolume() and a task is dispatched on the message loop to notify the + // filters. + float volume_; + + // Current playback rate (>= 0.0f). This value is set immediately via + // SetPlaybackRate() and a task is dispatched on the message loop to notify + // the filters. + float playback_rate_; + + // Current playback time. Set by filters. + base::TimeDelta time_; + + // Status of the pipeline. Initialized to PIPELINE_OK which indicates that + // the pipeline is operating correctly. Any other value indicates that the + // pipeline is stopped or is stopping. Clients can call the Stop() method to + // reset the pipeline state, and restore this to PIPELINE_OK. + PipelineError error_; + + // Vector of major mime types that have been rendered by this pipeline. + typedef std::set<std::string> RenderedMimeTypesSet; + RenderedMimeTypesSet rendered_mime_types_; + + // The following data members are only accessed by tasks posted to + // |message_loop_|. + // Member that tracks the current state. + enum State { + kCreated, + kInitDataSource, + kInitDemuxer, + kInitAudioDecoder, + kInitAudioRenderer, + kInitVideoDecoder, + kInitVideoRenderer, + kStarted, + kStopped, + kError, + }; State state_; // Filter factory as passed in by Start(). @@ -358,7 +283,7 @@ class PipelineInternal : public FilterHost, typedef std::vector<base::Thread*> FilterThreadVector; FilterThreadVector filter_threads_; - DISALLOW_COPY_AND_ASSIGN(PipelineInternal); + DISALLOW_COPY_AND_ASSIGN(PipelineImpl); }; } // namespace media |