1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
|
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#if !defined(MediaDataDemuxer_h)
#define MediaDataDemuxer_h
#include "mozilla/MozPromise.h"
#include "mozilla/UniquePtr.h"
#include "MediaData.h"
#include "MediaInfo.h"
#include "MediaResult.h"
#include "TimeUnits.h"
#include "nsISupportsImpl.h"
#include "mozilla/RefPtr.h"
#include "nsTArray.h"
namespace mozilla {
class MediaTrackDemuxer;
class TrackMetadataHolder;
// Allows reading the media data: to retrieve the metadata and demux samples.
// MediaDataDemuxer isn't designed to be thread safe.
// When used by the MediaFormatDecoder, care is taken to ensure that the demuxer
// will never be called from more than one thread at once.
class MediaDataDemuxer
{
public:
NS_INLINE_DECL_THREADSAFE_REFCOUNTING(MediaDataDemuxer)
typedef MozPromise<nsresult, MediaResult, /* IsExclusive = */ true> InitPromise;
// Initializes the demuxer. Other methods cannot be called unless
// initialization has completed and succeeded.
// Typically a demuxer will wait to parse the metadata before resolving the
// promise. The promise must not be resolved until sufficient data is
// supplied. For example, an incomplete metadata would cause the promise to be
// rejected should no more data be coming, while the demuxer would wait
// otherwise.
virtual RefPtr<InitPromise> Init() = 0;
// Returns true if a aType track type is available.
virtual bool HasTrackType(TrackInfo::TrackType aType) const = 0;
// Returns the number of tracks of aType type available. A value of
// 0 indicates that no such type is available.
virtual uint32_t GetNumberTracks(TrackInfo::TrackType aType) const = 0;
// Returns the MediaTrackDemuxer associated with aTrackNumber aType track.
// aTrackNumber is not to be confused with the Track ID.
// aTrackNumber must be constrained between 0 and GetNumberTracks(aType) - 1
// The actual Track ID is to be retrieved by calling
// MediaTrackDemuxer::TrackInfo.
virtual already_AddRefed<MediaTrackDemuxer> GetTrackDemuxer(TrackInfo::TrackType aType,
uint32_t aTrackNumber) = 0;
// Returns true if the underlying resource allows seeking.
virtual bool IsSeekable() const = 0;
// Returns true if the underlying resource can only seek within buffered
// ranges.
virtual bool IsSeekableOnlyInBufferedRanges() const { return false; }
// Returns the media's crypto information, or nullptr if media isn't
// encrypted.
virtual UniquePtr<EncryptionInfo> GetCrypto()
{
return nullptr;
}
// Notifies the demuxer that the underlying resource has received more data
// since the demuxer was initialized.
// The demuxer can use this mechanism to inform all track demuxers that new
// data is available and to refresh its buffered range.
virtual void NotifyDataArrived() { }
// Notifies the demuxer that the underlying resource has had data removed
// since the demuxer was initialized.
// The demuxer can use this mechanism to inform all track demuxers to update
// its buffered range.
// This will be called should the demuxer be used with MediaSourceResource.
virtual void NotifyDataRemoved() { }
// Indicate to MediaFormatReader if it should compute the start time
// of the demuxed data. If true (default) the first sample returned will be
// used as reference time base.
virtual bool ShouldComputeStartTime() const { return true; }
protected:
virtual ~MediaDataDemuxer()
{
}
};
class MediaTrackDemuxer
{
public:
NS_INLINE_DECL_THREADSAFE_REFCOUNTING(MediaTrackDemuxer)
class SamplesHolder {
public:
NS_INLINE_DECL_THREADSAFE_REFCOUNTING(SamplesHolder)
nsTArray<RefPtr<MediaRawData>> mSamples;
private:
~SamplesHolder() {}
};
class SkipFailureHolder {
public:
SkipFailureHolder(const MediaResult& aFailure, uint32_t aSkipped)
: mFailure(aFailure)
, mSkipped(aSkipped)
{}
MediaResult mFailure;
uint32_t mSkipped;
};
typedef MozPromise<media::TimeUnit, MediaResult, /* IsExclusive = */ true> SeekPromise;
typedef MozPromise<RefPtr<SamplesHolder>, MediaResult, /* IsExclusive = */ true> SamplesPromise;
typedef MozPromise<uint32_t, SkipFailureHolder, /* IsExclusive = */ true> SkipAccessPointPromise;
// Returns the TrackInfo (a.k.a Track Description) for this track.
// The TrackInfo returned will be:
// TrackInfo::kVideoTrack -> VideoInfo.
// TrackInfo::kAudioTrack -> AudioInfo.
// respectively.
virtual UniquePtr<TrackInfo> GetInfo() const = 0;
// Seeks to aTime. Upon success, SeekPromise will be resolved with the
// actual time seeked to. Typically the random access point time
virtual RefPtr<SeekPromise> Seek(media::TimeUnit aTime) = 0;
// Returns the next aNumSamples sample(s) available.
// If only a lesser amount of samples is available, only those will be
// returned.
// A aNumSamples value of -1 indicates to return all remaining samples.
// A video sample is typically made of a single video frame while an audio
// sample will contains multiple audio frames.
virtual RefPtr<SamplesPromise> GetSamples(int32_t aNumSamples = 1) = 0;
// Returns true if a call to GetSamples() may block while waiting on the
// underlying resource to return the data.
// This is used by the MediaFormatReader to determine if buffering heuristics
// should be used.
virtual bool GetSamplesMayBlock() const
{
return true;
}
// Cancel all pending actions (Seek, GetSamples) and reset current state
// All pending promises are to be rejected with CANCEL.
// The next call to GetSamples would return the first sample available in the
// track.
virtual void Reset() = 0;
// Returns timestamp of next random access point or an error if the demuxer
// can't report this.
virtual nsresult GetNextRandomAccessPoint(media::TimeUnit* aTime)
{
return NS_ERROR_NOT_IMPLEMENTED;
}
// Returns timestamp of previous random access point or an error if the
// demuxer can't report this.
virtual nsresult GetPreviousRandomAccessPoint(media::TimeUnit* aTime)
{
return NS_ERROR_NOT_IMPLEMENTED;
}
// Skip frames until the next Random Access Point located after
// aTimeThreshold.
// The first frame returned by the next call to GetSamples() will be the
// first random access point found after aTimeThreshold.
// Upon success, returns the number of frames skipped.
virtual RefPtr<SkipAccessPointPromise> SkipToNextRandomAccessPoint(media::TimeUnit aTimeThreshold) = 0;
// Gets the resource's offset used for the last Seek() or GetSample().
// A negative value indicates that this functionality isn't supported.
virtual int64_t GetResourceOffset() const
{
return -1;
}
virtual TrackInfo::TrackType GetType() const
{
return GetInfo()->GetType();
}
virtual media::TimeIntervals GetBuffered() = 0;
// By default, it is assumed that the entire resource can be evicted once
// all samples have been demuxed.
virtual int64_t GetEvictionOffset(const media::TimeUnit& aTime)
{
return INT64_MAX;
}
// If the MediaTrackDemuxer and MediaDataDemuxer hold cross references.
// BreakCycles must be overridden.
virtual void BreakCycles()
{
}
protected:
virtual ~MediaTrackDemuxer() {}
};
} // namespace mozilla
#endif // MediaDataDemuxer_h
|
