gecko/content/media/TrackUnionStream.h
Karl Tomlinson 59e9c70900 b=1010000 update mTracksKnownTime when finishing a stream r=roc
and use this in StreamBuffer::GetAllTracksEnd() to detect when no more tracks
will be added.

--HG--
extra : transplant_source : %B7A-%7EV%94%E1%CE%15%1C%15%7B%84%D5%F1%1D%A2%CF%EC%15
2014-05-19 08:26:54 +12:00

353 lines
16 KiB
C++

/* -*- Mode: C++; tab-width: 2; 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/. */
#ifndef MOZILLA_TRACKUNIONSTREAM_H_
#define MOZILLA_TRACKUNIONSTREAM_H_
#include "MediaStreamGraph.h"
#include <algorithm>
namespace mozilla {
#ifdef PR_LOGGING
#define STREAM_LOG(type, msg) PR_LOG(gMediaStreamGraphLog, type, msg)
#else
#define STREAM_LOG(type, msg)
#endif
/**
* See MediaStreamGraph::CreateTrackUnionStream.
* This file is only included by MediaStreamGraph.cpp so it's OK to put the
* entire implementation in this header file.
*/
class TrackUnionStream : public ProcessedMediaStream {
public:
TrackUnionStream(DOMMediaStream* aWrapper) :
ProcessedMediaStream(aWrapper),
mFilterCallback(nullptr),
mMaxTrackID(0) {}
virtual void RemoveInput(MediaInputPort* aPort) MOZ_OVERRIDE
{
for (int32_t i = mTrackMap.Length() - 1; i >= 0; --i) {
if (mTrackMap[i].mInputPort == aPort) {
EndTrack(i);
mTrackMap.RemoveElementAt(i);
}
}
ProcessedMediaStream::RemoveInput(aPort);
}
virtual void ProcessInput(GraphTime aFrom, GraphTime aTo, uint32_t aFlags) MOZ_OVERRIDE
{
if (IsFinishedOnGraphThread()) {
return;
}
nsAutoTArray<bool,8> mappedTracksFinished;
nsAutoTArray<bool,8> mappedTracksWithMatchingInputTracks;
for (uint32_t i = 0; i < mTrackMap.Length(); ++i) {
mappedTracksFinished.AppendElement(true);
mappedTracksWithMatchingInputTracks.AppendElement(false);
}
bool allFinished = true;
bool allHaveCurrentData = true;
for (uint32_t i = 0; i < mInputs.Length(); ++i) {
MediaStream* stream = mInputs[i]->GetSource();
if (!stream->IsFinishedOnGraphThread()) {
// XXX we really should check whether 'stream' has finished within time aTo,
// not just that it's finishing when all its queued data eventually runs
// out.
allFinished = false;
}
if (!stream->HasCurrentData()) {
allHaveCurrentData = false;
}
for (StreamBuffer::TrackIter tracks(stream->GetStreamBuffer());
!tracks.IsEnded(); tracks.Next()) {
bool found = false;
for (uint32_t j = 0; j < mTrackMap.Length(); ++j) {
TrackMapEntry* map = &mTrackMap[j];
if (map->mInputPort == mInputs[i] && map->mInputTrackID == tracks->GetID()) {
bool trackFinished;
StreamBuffer::Track* outputTrack = mBuffer.FindTrack(map->mOutputTrackID);
if (!outputTrack || outputTrack->IsEnded()) {
trackFinished = true;
} else {
CopyTrackData(tracks.get(), j, aFrom, aTo, &trackFinished);
}
mappedTracksFinished[j] = trackFinished;
mappedTracksWithMatchingInputTracks[j] = true;
found = true;
break;
}
}
if (!found && (!mFilterCallback || mFilterCallback(tracks.get()))) {
bool trackFinished = false;
uint32_t mapIndex = AddTrack(mInputs[i], tracks.get(), aFrom);
CopyTrackData(tracks.get(), mapIndex, aFrom, aTo, &trackFinished);
mappedTracksFinished.AppendElement(trackFinished);
mappedTracksWithMatchingInputTracks.AppendElement(true);
}
}
}
for (int32_t i = mTrackMap.Length() - 1; i >= 0; --i) {
if (mappedTracksFinished[i]) {
EndTrack(i);
} else {
allFinished = false;
}
if (!mappedTracksWithMatchingInputTracks[i]) {
mTrackMap.RemoveElementAt(i);
}
}
if (allFinished && mAutofinish && (aFlags & ALLOW_FINISH)) {
// All streams have finished and won't add any more tracks, and
// all our tracks have actually finished and been removed from our map,
// so we're finished now.
FinishOnGraphThread();
} else {
mBuffer.AdvanceKnownTracksTime(GraphTimeToStreamTime(aTo));
}
if (allHaveCurrentData) {
// We can make progress if we're not blocked
mHasCurrentData = true;
}
}
// Consumers may specify a filtering callback to apply to every input track.
// Returns true to allow the track to act as an input; false to reject it entirely.
typedef bool (*TrackIDFilterCallback)(StreamBuffer::Track*);
void SetTrackIDFilter(TrackIDFilterCallback aCallback) {
mFilterCallback = aCallback;
}
// Forward SetTrackEnabled(output_track_id, enabled) to the Source MediaStream,
// translating the output track ID into the correct ID in the source.
virtual void ForwardTrackEnabled(TrackID aOutputID, bool aEnabled) MOZ_OVERRIDE {
for (int32_t i = mTrackMap.Length() - 1; i >= 0; --i) {
if (mTrackMap[i].mOutputTrackID == aOutputID) {
mTrackMap[i].mInputPort->GetSource()->
SetTrackEnabled(mTrackMap[i].mInputTrackID, aEnabled);
}
}
}
protected:
TrackIDFilterCallback mFilterCallback;
// Only non-ended tracks are allowed to persist in this map.
struct TrackMapEntry {
// mEndOfConsumedInputTicks is the end of the input ticks that we've consumed.
// 0 if we haven't consumed any yet.
TrackTicks mEndOfConsumedInputTicks;
// mEndOfLastInputIntervalInInputStream is the timestamp for the end of the
// previous interval which was unblocked for both the input and output
// stream, in the input stream's timeline, or -1 if there wasn't one.
StreamTime mEndOfLastInputIntervalInInputStream;
// mEndOfLastInputIntervalInOutputStream is the timestamp for the end of the
// previous interval which was unblocked for both the input and output
// stream, in the output stream's timeline, or -1 if there wasn't one.
StreamTime mEndOfLastInputIntervalInOutputStream;
MediaInputPort* mInputPort;
// We keep track IDs instead of track pointers because
// tracks can be removed without us being notified (e.g.
// when a finished track is forgotten.) When we need a Track*,
// we call StreamBuffer::FindTrack, which will return null if
// the track has been deleted.
TrackID mInputTrackID;
TrackID mOutputTrackID;
nsAutoPtr<MediaSegment> mSegment;
};
uint32_t AddTrack(MediaInputPort* aPort, StreamBuffer::Track* aTrack,
GraphTime aFrom)
{
// Use the ID of the source track if we can, otherwise allocate a new
// unique ID
TrackID id = std::max(mMaxTrackID + 1, aTrack->GetID());
mMaxTrackID = id;
TrackRate rate = aTrack->GetRate();
// Round up the track start time so the track, if anything, starts a
// little later than the true time. This means we'll have enough
// samples in our input stream to go just beyond the destination time.
TrackTicks outputStart = TimeToTicksRoundUp(rate, GraphTimeToStreamTime(aFrom));
nsAutoPtr<MediaSegment> segment;
segment = aTrack->GetSegment()->CreateEmptyClone();
for (uint32_t j = 0; j < mListeners.Length(); ++j) {
MediaStreamListener* l = mListeners[j];
l->NotifyQueuedTrackChanges(Graph(), id, rate, outputStart,
MediaStreamListener::TRACK_EVENT_CREATED,
*segment);
}
segment->AppendNullData(outputStart);
StreamBuffer::Track* track =
&mBuffer.AddTrack(id, rate, outputStart, segment.forget());
STREAM_LOG(PR_LOG_DEBUG, ("TrackUnionStream %p adding track %d for input stream %p track %d, start ticks %lld",
this, id, aPort->GetSource(), aTrack->GetID(),
(long long)outputStart));
TrackMapEntry* map = mTrackMap.AppendElement();
map->mEndOfConsumedInputTicks = 0;
map->mEndOfLastInputIntervalInInputStream = -1;
map->mEndOfLastInputIntervalInOutputStream = -1;
map->mInputPort = aPort;
map->mInputTrackID = aTrack->GetID();
map->mOutputTrackID = track->GetID();
map->mSegment = aTrack->GetSegment()->CreateEmptyClone();
return mTrackMap.Length() - 1;
}
void EndTrack(uint32_t aIndex)
{
StreamBuffer::Track* outputTrack = mBuffer.FindTrack(mTrackMap[aIndex].mOutputTrackID);
if (!outputTrack || outputTrack->IsEnded())
return;
for (uint32_t j = 0; j < mListeners.Length(); ++j) {
MediaStreamListener* l = mListeners[j];
TrackTicks offset = outputTrack->GetSegment()->GetDuration();
nsAutoPtr<MediaSegment> segment;
segment = outputTrack->GetSegment()->CreateEmptyClone();
l->NotifyQueuedTrackChanges(Graph(), outputTrack->GetID(),
outputTrack->GetRate(), offset,
MediaStreamListener::TRACK_EVENT_ENDED,
*segment);
}
outputTrack->SetEnded();
}
void CopyTrackData(StreamBuffer::Track* aInputTrack,
uint32_t aMapIndex, GraphTime aFrom, GraphTime aTo,
bool* aOutputTrackFinished)
{
TrackMapEntry* map = &mTrackMap[aMapIndex];
StreamBuffer::Track* outputTrack = mBuffer.FindTrack(map->mOutputTrackID);
MOZ_ASSERT(outputTrack && !outputTrack->IsEnded(), "Can't copy to ended track");
TrackRate rate = outputTrack->GetRate();
MediaSegment* segment = map->mSegment;
MediaStream* source = map->mInputPort->GetSource();
GraphTime next;
*aOutputTrackFinished = false;
for (GraphTime t = aFrom; t < aTo; t = next) {
MediaInputPort::InputInterval interval = map->mInputPort->GetNextInputInterval(t);
interval.mEnd = std::min(interval.mEnd, aTo);
StreamTime inputEnd = source->GraphTimeToStreamTime(interval.mEnd);
TrackTicks inputTrackEndPoint = TRACK_TICKS_MAX;
if (aInputTrack->IsEnded() &&
aInputTrack->GetEndTimeRoundDown() <= inputEnd) {
inputTrackEndPoint = aInputTrack->GetEnd();
*aOutputTrackFinished = true;
}
if (interval.mStart >= interval.mEnd)
break;
next = interval.mEnd;
// Ticks >= startTicks and < endTicks are in the interval
StreamTime outputEnd = GraphTimeToStreamTime(interval.mEnd);
TrackTicks startTicks = outputTrack->GetEnd();
StreamTime outputStart = GraphTimeToStreamTime(interval.mStart);
NS_WARN_IF_FALSE(startTicks == TimeToTicksRoundUp(rate, outputStart),
"Samples missing");
TrackTicks endTicks = TimeToTicksRoundUp(rate, outputEnd);
TrackTicks ticks = endTicks - startTicks;
StreamTime inputStart = source->GraphTimeToStreamTime(interval.mStart);
if (interval.mInputIsBlocked) {
// Maybe the input track ended?
segment->AppendNullData(ticks);
STREAM_LOG(PR_LOG_DEBUG+1, ("TrackUnionStream %p appending %lld ticks of null data to track %d",
this, (long long)ticks, outputTrack->GetID()));
} else {
// Figuring out which samples to use from the input stream is tricky
// because its start time and our start time may differ by a fraction
// of a tick. Assuming the input track hasn't ended, we have to ensure
// that 'ticks' samples are gathered, even though a tick boundary may
// occur between outputStart and outputEnd but not between inputStart
// and inputEnd.
// These are the properties we need to ensure:
// 1) Exactly 'ticks' ticks of output are produced, i.e.
// inputEndTicks - inputStartTicks = ticks.
// 2) inputEndTicks <= aInputTrack->GetSegment()->GetDuration().
// 3) In any sequence of intervals where neither stream is blocked,
// the content of the input track we use is a contiguous sequence of
// ticks with no gaps or overlaps.
if (map->mEndOfLastInputIntervalInInputStream != inputStart ||
map->mEndOfLastInputIntervalInOutputStream != outputStart) {
// Start of a new series of intervals where neither stream is blocked.
map->mEndOfConsumedInputTicks = TimeToTicksRoundDown(rate, inputStart) - 1;
}
TrackTicks inputStartTicks = map->mEndOfConsumedInputTicks;
TrackTicks inputEndTicks = inputStartTicks + ticks;
map->mEndOfConsumedInputTicks = inputEndTicks;
map->mEndOfLastInputIntervalInInputStream = inputEnd;
map->mEndOfLastInputIntervalInOutputStream = outputEnd;
// Now we prove that the above properties hold:
// Property #1: trivial by construction.
// Property #3: trivial by construction. Between every two
// intervals where both streams are not blocked, the above if condition
// is false and mEndOfConsumedInputTicks advances exactly to match
// the ticks that were consumed.
// Property #2:
// Let originalOutputStart be the value of outputStart and originalInputStart
// be the value of inputStart when the body of the "if" block was last
// executed.
// Let allTicks be the sum of the values of 'ticks' computed since then.
// The interval [originalInputStart/rate, inputEnd/rate) is the
// same length as the interval [originalOutputStart/rate, outputEnd/rate),
// so the latter interval can have at most one more integer in it. Thus
// TimeToTicksRoundUp(rate, outputEnd) - TimeToTicksRoundUp(rate, originalOutputStart)
// <= TimeToTicksRoundDown(rate, inputEnd) - TimeToTicksRoundDown(rate, originalInputStart) + 1
// Then
// inputEndTicks = TimeToTicksRoundDown(rate, originalInputStart) - 1 + allTicks
// = TimeToTicksRoundDown(rate, originalInputStart) - 1 + TimeToTicksRoundUp(rate, outputEnd) - TimeToTicksRoundUp(rate, originalOutputStart)
// <= TimeToTicksRoundDown(rate, originalInputStart) - 1 + TimeToTicksRoundDown(rate, inputEnd) - TimeToTicksRoundDown(rate, originalInputStart) + 1
// = TimeToTicksRoundDown(rate, inputEnd)
// <= inputEnd/rate
// (now using the fact that inputEnd <= track->GetEndTimeRoundDown() for a non-ended track)
// <= TicksToTimeRoundDown(rate, aInputTrack->GetSegment()->GetDuration())/rate
// <= rate*aInputTrack->GetSegment()->GetDuration()/rate
// = aInputTrack->GetSegment()->GetDuration()
// as required.
if (inputStartTicks < 0) {
// Data before the start of the track is just null.
// We have to add a small amount of delay to ensure that there is
// always a sample available if we see an interval that contains a
// tick boundary on the output stream's timeline but does not contain
// a tick boundary on the input stream's timeline. 1 tick delay is
// necessary and sufficient.
segment->AppendNullData(-inputStartTicks);
inputStartTicks = 0;
}
if (inputEndTicks > inputStartTicks) {
segment->AppendSlice(*aInputTrack->GetSegment(),
std::min(inputTrackEndPoint, inputStartTicks),
std::min(inputTrackEndPoint, inputEndTicks));
}
STREAM_LOG(PR_LOG_DEBUG+1, ("TrackUnionStream %p appending %lld ticks of input data to track %d",
this, (long long)(std::min(inputTrackEndPoint, inputEndTicks) - std::min(inputTrackEndPoint, inputStartTicks)),
outputTrack->GetID()));
}
ApplyTrackDisabling(outputTrack->GetID(), segment);
for (uint32_t j = 0; j < mListeners.Length(); ++j) {
MediaStreamListener* l = mListeners[j];
l->NotifyQueuedTrackChanges(Graph(), outputTrack->GetID(),
outputTrack->GetRate(), startTicks, 0,
*segment);
}
outputTrack->GetSegment()->AppendFrom(segment);
}
}
nsTArray<TrackMapEntry> mTrackMap;
TrackID mMaxTrackID;
};
}
#endif /* MOZILLA_MEDIASTREAMGRAPH_H_ */