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// Copyright (c) 2012 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.
#ifndef MEDIA_BASE_DEMUXER_H_
#define MEDIA_BASE_DEMUXER_H_
#include <stdint.h>
#include <memory>
#include <vector>
#include "base/macros.h"
#include "base/optional.h"
#include "base/time/time.h"
#include "media/base/data_source.h"
#include "media/base/demuxer_stream.h"
#include "media/base/eme_constants.h"
#include "media/base/media_export.h"
#include "media/base/media_resource.h"
#include "media/base/media_track.h"
#include "media/base/pipeline_status.h"
#include "media/base/ranges.h"
namespace media {
class MediaTracks;
class MEDIA_EXPORT DemuxerHost {
public:
// Notify the host that buffered time ranges have changed. Note that buffered
// time ranges can grow (when new media data is appended), but they can also
// shrink (when buffering reaches limit capacity and some buffered data
// becomes evicted, e.g. due to MSE GC algorithm, or by explicit removal of
// ranges directed by MSE web app).
virtual void OnBufferedTimeRangesChanged(
const Ranges<base::TimeDelta>& ranges) = 0;
// Sets the duration of the media in microseconds.
// Duration may be kInfiniteDuration if the duration is not known.
virtual void SetDuration(base::TimeDelta duration) = 0;
// Stops execution of the pipeline due to a fatal error. Do not call this
// method with PIPELINE_OK. Stopping is not immediate so demuxers must be
// prepared to soft fail on subsequent calls. E.g., if Demuxer::Seek() is
// called after an unrecoverable error the provided PipelineStatusCB must be
// called with an error.
virtual void OnDemuxerError(PipelineStatus error) = 0;
protected:
virtual ~DemuxerHost();
};
class MEDIA_EXPORT Demuxer : public MediaResource {
public:
// A new potentially encrypted stream has been parsed.
// First parameter - The type of initialization data.
// Second parameter - The initialization data associated with the stream.
using EncryptedMediaInitDataCB =
base::Callback<void(EmeInitDataType type,
const std::vector<uint8_t>& init_data)>;
// Notifies demuxer clients that media track configuration has been updated
// (e.g. the initial stream metadata has been parsed successfully, or a new
// init segment has been parsed successfully in MSE case).
using MediaTracksUpdatedCB =
base::Callback<void(std::unique_ptr<MediaTracks>)>;
// Called once the demuxer has finished enabling or disabling tracks. The type
// argument is required because the vector may be empty.
using TrackChangeCB =
base::OnceCallback<void(DemuxerStream::Type type,
const std::vector<DemuxerStream*>&)>;
Demuxer();
~Demuxer() override;
// Returns the name of the demuxer for logging purpose.
virtual std::string GetDisplayName() const = 0;
// Completes initialization of the demuxer.
//
// The demuxer does not own |host| as it is guaranteed to outlive the
// lifetime of the demuxer. Don't delete it! |status_cb| must only be run
// after this method has returned.
virtual void Initialize(DemuxerHost* host,
const PipelineStatusCB& status_cb) = 0;
// Aborts any pending read operations that the demuxer is involved with; any
// read aborted will be aborted with a status of kAborted. Future reads will
// also be aborted until Seek() is called.
virtual void AbortPendingReads() = 0;
// Indicates that a new Seek() call is on its way. Implementations may abort
// pending reads and future Read() calls may return kAborted until Seek() is
// executed. |seek_time| is the presentation timestamp of the new Seek() call.
//
// In actual use, this call occurs on the main thread while Seek() is called
// on the media thread. StartWaitingForSeek() can be used to synchronize the
// two.
//
// StartWaitingForSeek() MUST be called before Seek().
virtual void StartWaitingForSeek(base::TimeDelta seek_time) = 0;
// Indicates that the current Seek() operation is obsoleted by a new one.
// Implementations can expect that StartWaitingForSeek() will be called
// when the current seek operation completes.
//
// Like StartWaitingForSeek(), CancelPendingSeek() is called on the main
// thread. Ordering with respect to the to-be-canceled Seek() is not
// guaranteed. Regardless of ordering, implementations may abort pending reads
// and may return kAborted from future Read() calls, until after
// StartWaitingForSeek() and the following Seek() call occurs.
//
// |seek_time| should match that passed to the next StartWaitingForSeek(), but
// may not if the seek target changes again before the current seek operation
// completes or is aborted.
virtual void CancelPendingSeek(base::TimeDelta seek_time) = 0;
// Carry out any actions required to seek to the given time, executing the
// callback upon completion.
virtual void Seek(base::TimeDelta time,
const PipelineStatusCB& status_cb) = 0;
// Stops this demuxer.
//
// After this call the demuxer may be destroyed. It is illegal to call any
// method (including Stop()) after a demuxer has stopped.
virtual void Stop() = 0;
// Returns the starting time for the media file; it's always positive.
virtual base::TimeDelta GetStartTime() const = 0;
// Returns Time represented by presentation timestamp 0.
// If the timstamps are not associated with a Time, then
// a null Time is returned.
virtual base::Time GetTimelineOffset() const = 0;
// Returns the memory usage in bytes for the demuxer.
virtual int64_t GetMemoryUsage() const = 0;
// The |track_ids| vector has either 1 track, or is empty, indicating that
// all tracks should be disabled. |change_completed_cb| is fired after the
// demuxer streams are disabled, however this callback should then notify
// the appropriate renderer in order for tracks to be switched fully.
virtual void OnEnabledAudioTracksChanged(
const std::vector<MediaTrack::Id>& track_ids,
base::TimeDelta curr_time,
TrackChangeCB change_completed_cb) = 0;
virtual void OnSelectedVideoTrackChanged(
const std::vector<MediaTrack::Id>& track_ids,
base::TimeDelta curr_time,
TrackChangeCB change_completed_cb) = 0;
private:
DISALLOW_COPY_AND_ASSIGN(Demuxer);
};
} // namespace media
#endif // MEDIA_BASE_DEMUXER_H_