1 // Copyright 2014 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
5 #ifndef MEDIA_BASE_RENDERER_H_
6 #define MEDIA_BASE_RENDERER_H_
8 #include "base/callback.h"
9 #include "base/time/time.h"
10 #include "media/base/buffering_state.h"
11 #include "media/base/media_export.h"
12 #include "media/base/pipeline_status.h"
18 class MEDIA_EXPORT Renderer {
20 typedef base::Callback<base::TimeDelta()> TimeDeltaCB;
24 // Stops rendering and fires any pending callbacks.
27 // Initializes the Renderer, executing |init_cb| upon completion.
28 // If initialization failed, fires |error_cb| before |init_cb|.
30 // Permanent callbacks:
31 // - |statistics_cb|: Executed periodically with rendering statistics.
32 // - |time_cb|: Executed whenever time has advanced through rendering.
33 // - |ended_cb|: Executed when rendering has reached the end of stream.
34 // - |error_cb|: Executed if any error was encountered during rendering.
35 virtual void Initialize(const base::Closure& init_cb,
36 const StatisticsCB& statistics_cb,
37 const base::Closure& ended_cb,
38 const PipelineStatusCB& error_cb,
39 const BufferingStateCB& buffering_state_cb) = 0;
41 // The following functions must be called after Initialize().
43 // Discards any buffered data, executing |flush_cb| when completed.
44 virtual void Flush(const base::Closure& flush_cb) = 0;
46 // Starts rendering from |time|.
47 virtual void StartPlayingFrom(base::TimeDelta time) = 0;
49 // Updates the current playback rate. The default playback rate should be 1.
50 virtual void SetPlaybackRate(float playback_rate) = 0;
52 // Sets the output volume. The default volume should be 1.
53 virtual void SetVolume(float volume) = 0;
55 // Returns the current media time.
56 virtual base::TimeDelta GetMediaTime() = 0;
58 // Returns whether |this| renders audio.
59 virtual bool HasAudio() = 0;
61 // Returns whether |this| renders video.
62 virtual bool HasVideo() = 0;
64 // Associates the |cdm| with this Renderer.
65 virtual void SetCdm(MediaKeys* cdm) = 0;
68 DISALLOW_COPY_AND_ASSIGN(Renderer);
73 #endif // MEDIA_BASE_RENDERER_H_