diff options
Diffstat (limited to 'media/base/pipeline.h')
| -rw-r--r-- | media/base/pipeline.h | 163 |
1 files changed, 69 insertions, 94 deletions
diff --git a/media/base/pipeline.h b/media/base/pipeline.h index 66dab005..d418e4b 100644 --- a/media/base/pipeline.h +++ b/media/base/pipeline.h @@ -1,4 +1,4 @@ -// Copyright (c) 2006-2009 The Chromium Authors. All rights reserved. +// Copyright (c) 2009 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. @@ -15,7 +15,7 @@ #include "media/base/factory.h" namespace base { - class TimeDelta; +class TimeDelta; } namespace media { @@ -44,88 +44,15 @@ enum PipelineError { DEMUXER_ERROR_COULD_NOT_CREATE_THREAD, }; -// Base class for Pipeline class which allows for read-only access to members. -// Filters are allowed to access the PipelineStatus interface but are not given -// access to the client Pipeline methods. -class PipelineStatus { - public: - // Returns the current initialization state of the pipeline. Clients can - // examine this to determine if it is acceptable to call SetRate/SetVolume/ - // Seek after calling Start on the pipeline. Note that this will be - // set to true prior to a call to the client's |init_complete_callback| if - // initialization is successful. - virtual bool IsInitialized() const = 0; - - // Get the duration of the media in microseconds. If the duration has not - // been determined yet, then returns 0. - virtual base::TimeDelta GetDuration() const = 0; - - // Get the approximate amount of playable data buffered so far in micro- - // seconds. - virtual base::TimeDelta GetBufferedTime() const = 0; - - // Get the total size of the media file. If the size has not yet been - // determined or can not be determined, this value is 0. - virtual int64 GetTotalBytes() const = 0; - - // Get the total number of bytes that are buffered on the client and ready to - // be played. - virtual int64 GetBufferedBytes() const = 0; - - // Gets the size of the video output in pixel units. If there is no video - // or the video has not been rendered yet, the width and height will be 0. - virtual void GetVideoSize(size_t* width_out, size_t* height_out) const = 0; - - // Gets the current volume setting being used by the audio renderer. When - // the pipeline is started, this value will be 1.0f. Valid values range - // from 0.0f to 1.0f. - virtual float GetVolume() const = 0; - - // Gets the current playback rate of the pipeline. When the pipeline is - // started, the playback rate will be 0.0f. A rate of 1.0f indicates - // that the pipeline is rendering the media at the standard rate. Valid - // values for playback rate are >= 0.0f. - virtual float GetPlaybackRate() const = 0; - - // Gets the current pipeline time in microseconds. For a pipeline "time" - // progresses from 0 to the end of the media. This time base is updated - // by the audio renderer to allow for synchronization of audio and video. - // Note that a more accurate time may be obtained by calling the - // GetInterpolatedTime method which estimates the position of the audio - // device based on a combination of the last time the audio device reported - // it's position and the current system time. - virtual base::TimeDelta GetTime() const = 0; - - // Gets the current pipeline time in microseconds. For a pipeline "time" - // progresses from 0 to the end of the media. Becuase this method provides - // an estimated time, it is possible that subsequent calls to this method will - // actually progress backwards slightly, so callers must not assume that this - // method will always return times larger than the last one. - virtual base::TimeDelta GetInterpolatedTime() const = 0; - - // Gets the current error status for the pipeline. If the pipeline is - // operating correctly, this will return OK. - virtual PipelineError GetError() const = 0; - - // If the |major_mime_type| exists in the pipeline and is being rendered, this - // method will return true. Types are defined in media/base/media_foramt.h. - // For example, to determine if a pipeline contains video: - // bool has_video = pipeline->IsRendered(mime_type::kMajorTypeVideo); - virtual bool IsRendered(const std::string& major_mime_type) const = 0; - - protected: - virtual ~PipelineStatus() {} -}; - // Client-provided callbacks for various pipeline operations. // // TODO(scherkus): consider returning a PipelineError instead of a bool, or // perhaps a client callback interface. typedef Callback1<bool>::Type PipelineCallback; -class Pipeline : public PipelineStatus { +class Pipeline { public: - // Build a pipeline to render the given URI using the given filter factory to + // Build a pipeline to render the given URL using the given filter factory to // construct a filter chain. Returns true if successful, false otherwise // (i.e., pipeline already started). Note that a return value of true // only indicates that the initialization process has started successfully. @@ -149,42 +76,90 @@ class Pipeline : public PipelineStatus { // the pipeline class, not on the thread that originally called the Start() // method. virtual bool Start(FilterFactory* filter_factory, - const std::string& uri, + const std::string& url, PipelineCallback* start_callback) = 0; // Stops the pipeline and resets to an uninitialized state. This method // will block the calling thread until the pipeline has been completely - // torn down and reset to an uninitialized state. After calling Stop, it - // is acceptable to call Start again since Stop leaves the pipeline + // torn down and reset to an uninitialized state. After calling Stop(), it + // is acceptable to call Start() again since Stop() leaves the pipeline // in a state identical to a newly created pipeline. - // Calling this method is not strictly required because the pipeline - // destructor will stop it pipeline if it has not been stopped already. + // + // Stop() must be called before destroying the pipeline. + // + // TODO(scherkus): it shouldn't be acceptable to call Start() again after you + // Stop() a pipeline -- it should be destroyed and replaced with a new + // instance. virtual void Stop() = 0; + // Attempt to seek to the position specified by time. |seek_callback| will be + // executed when the all filters in the pipeline have processed the seek. + // The callback will return true if the seek was carried out, false otherwise + // (i.e., streaming media). + virtual void Seek(base::TimeDelta time, PipelineCallback* seek_callback) = 0; + + // Returns the current initialization state of the pipeline. Note that this + // will be set to true prior to a executing |init_complete_callback| if + // initialization is successful. + virtual bool IsInitialized() const = 0; + + // If the |major_mime_type| exists in the pipeline and is being rendered, this + // method will return true. Types are defined in media/base/media_foramt.h. + // For example, to determine if a pipeline contains video: + // bool has_video = pipeline->IsRendered(mime_type::kMajorTypeVideo); + virtual bool IsRendered(const std::string& major_mime_type) const = 0; + + // Gets the current playback rate of the pipeline. When the pipeline is + // started, the playback rate will be 0.0f. A rate of 1.0f indicates + // that the pipeline is rendering the media at the standard rate. Valid + // values for playback rate are >= 0.0f. + virtual float GetPlaybackRate() const = 0; + // Attempt to adjust the playback rate. Setting a playback rate of 0.0f pauses // all rendering of the media. A rate of 1.0f indicates a normal playback // rate. Values for the playback rate must be greater than or equal to 0.0f. - // TODO(ralphl): What about maximum rate? Does HTML5 specify a max? // - // This method must be called only after initialization has completed. + // TODO(scherkus): What about maximum rate? Does HTML5 specify a max? virtual void SetPlaybackRate(float playback_rate) = 0; - // Attempt to seek to the position specified by time. |seek_callback| will be - // executed when the all filters in the pipeline have processed the seek. - // The callback will return true if the seek was carried out, false otherwise - // (i.e., streaming media). - // - // This method must be called only after initialization has completed. - virtual void Seek(base::TimeDelta time, - PipelineCallback* seek_callback) = 0; + // Gets the current volume setting being used by the audio renderer. When + // the pipeline is started, this value will be 1.0f. Valid values range + // from 0.0f to 1.0f. + virtual float GetVolume() const = 0; // Attempt to set the volume of the audio renderer. Valid values for volume // range from 0.0f (muted) to 1.0f (full volume). This value affects all // channels proportionately for multi-channel audio streams. - // - // This method must be called only after initialization has completed. virtual void SetVolume(float volume) = 0; + // Gets the current pipeline time. For a pipeline "time" progresses from 0 to + // the end of the media. + virtual base::TimeDelta GetTime() const = 0; + + // Get the approximate amount of playable data buffered so far in micro- + // seconds. + virtual base::TimeDelta GetBufferedTime() const = 0; + + // Get the duration of the media in microseconds. If the duration has not + // been determined yet, then returns 0. + virtual base::TimeDelta GetDuration() const = 0; + + // Get the total number of bytes that are buffered on the client and ready to + // be played. + virtual int64 GetBufferedBytes() const = 0; + + // Get the total size of the media file. If the size has not yet been + // determined or can not be determined, this value is 0. + virtual int64 GetTotalBytes() const = 0; + + // Gets the size of the video output in pixel units. If there is no video + // or the video has not been rendered yet, the width and height will be 0. + virtual void GetVideoSize(size_t* width_out, size_t* height_out) const = 0; + + // Gets the current error status for the pipeline. If the pipeline is + // operating correctly, this will return OK. + virtual PipelineError GetError() const = 0; + protected: virtual ~Pipeline() {} }; |