DXR is a code search and navigation tool aimed at making sense of large projects. It supports full-text and regex searches as well as structural queries.

Header

Mercurial (fddffdeab170)

VCS Links

Line Code
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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451
/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sw=2 sts=2 et cindent: */
/* 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/. */

#include <algorithm>
#include <limits>
#include <stdint.h>

#include "MP4Demuxer.h"
#include "mp4_demuxer/MoofParser.h"
#include "mp4_demuxer/MP4Metadata.h"
#include "mp4_demuxer/ResourceStream.h"
#include "mp4_demuxer/BufferStream.h"
#include "mp4_demuxer/Index.h"

// Used for telemetry
#include "mozilla/Telemetry.h"
#include "mp4_demuxer/AnnexB.h"
#include "mp4_demuxer/H264.h"

PRLogModuleInfo* GetDemuxerLog() {
  static PRLogModuleInfo* log = nullptr;
  if (!log) {
    log = PR_NewLogModule("MP4Demuxer");
  }
  return log;
}

namespace mozilla {

class MP4TrackDemuxer : public MediaTrackDemuxer
{
public:
  MP4TrackDemuxer(MP4Demuxer* aParent,
                  UniquePtr<TrackInfo>&& aInfo,
                  const nsTArray<mp4_demuxer::Index::Indice>& indices);

  virtual UniquePtr<TrackInfo> GetInfo() const override;

  virtual RefPtr<SeekPromise> Seek(media::TimeUnit aTime) override;

  virtual RefPtr<SamplesPromise> GetSamples(int32_t aNumSamples = 1) override;

  virtual void Reset() override;

  virtual nsresult GetNextRandomAccessPoint(media::TimeUnit* aTime) override;

  RefPtr<SkipAccessPointPromise> SkipToNextRandomAccessPoint(media::TimeUnit aTimeThreshold) override;

  virtual media::TimeIntervals GetBuffered() override;

  virtual void BreakCycles() override;

private:
  friend class MP4Demuxer;
  void NotifyDataArrived();
  void UpdateSamples(nsTArray<RefPtr<MediaRawData>>& aSamples);
  void EnsureUpToDateIndex();
  void SetNextKeyFrameTime();
  RefPtr<MP4Demuxer> mParent;
  RefPtr<mp4_demuxer::ResourceStream> mStream;
  UniquePtr<TrackInfo> mInfo;
  // We do not actually need a monitor, however MoofParser (in mIndex) will
  // assert if a monitor isn't held.
  Monitor mMonitor;
  RefPtr<mp4_demuxer::Index> mIndex;
  UniquePtr<mp4_demuxer::SampleIterator> mIterator;
  Maybe<media::TimeUnit> mNextKeyframeTime;
  // Queued samples extracted by the demuxer, but not yet returned.
  RefPtr<MediaRawData> mQueuedSample;
  bool mNeedReIndex;
  bool mNeedSPSForTelemetry;
};


// Returns true if no SPS was found and search for it should continue.
bool
AccumulateSPSTelemetry(const MediaByteBuffer* aExtradata)
{
  mp4_demuxer::SPSData spsdata;
  if (mp4_demuxer::H264::DecodeSPSFromExtraData(aExtradata, spsdata)) {
    uint8_t constraints = (spsdata.constraint_set0_flag ? (1 << 0) : 0) |
                          (spsdata.constraint_set1_flag ? (1 << 1) : 0) |
                          (spsdata.constraint_set2_flag ? (1 << 2) : 0) |
                          (spsdata.constraint_set3_flag ? (1 << 3) : 0) |
                          (spsdata.constraint_set4_flag ? (1 << 4) : 0) |
                          (spsdata.constraint_set5_flag ? (1 << 5) : 0);
    Telemetry::Accumulate(Telemetry::VIDEO_DECODED_H264_SPS_CONSTRAINT_SET_FLAG,
                          constraints);

    // Collect profile_idc values up to 244, otherwise 0 for unknown.
    Telemetry::Accumulate(Telemetry::VIDEO_DECODED_H264_SPS_PROFILE,
                          spsdata.profile_idc <= 244 ? spsdata.profile_idc : 0);

    // Make sure level_idc represents a value between levels 1 and 5.2,
    // otherwise collect 0 for unknown level.
    Telemetry::Accumulate(Telemetry::VIDEO_DECODED_H264_SPS_LEVEL,
                          (spsdata.level_idc >= 10 && spsdata.level_idc <= 52) ?
                          spsdata.level_idc : 0);

    // max_num_ref_frames should be between 0 and 16, anything larger will
    // be treated as invalid.
    Telemetry::Accumulate(Telemetry::VIDEO_H264_SPS_MAX_NUM_REF_FRAMES,
                          std::min(spsdata.max_num_ref_frames, 17u));

    return false;
  }

  return true;
}

MP4Demuxer::MP4Demuxer(MediaResource* aResource)
  : mResource(aResource)
  , mStream(new mp4_demuxer::ResourceStream(aResource))
  , mInitData(new MediaByteBuffer)
{
}

RefPtr<MP4Demuxer::InitPromise>
MP4Demuxer::Init()
{
  AutoPinned<mp4_demuxer::ResourceStream> stream(mStream);

  // Check that we have enough data to read the metadata.
  if (!mp4_demuxer::MP4Metadata::HasCompleteMetadata(stream)) {
    return InitPromise::CreateAndReject(DemuxerFailureReason::DEMUXER_ERROR, __func__);
  }

  mInitData = mp4_demuxer::MP4Metadata::Metadata(stream);
  if (!mInitData) {
    // OOM
    return InitPromise::CreateAndReject(DemuxerFailureReason::DEMUXER_ERROR, __func__);
  }

  RefPtr<mp4_demuxer::BufferStream> bufferstream =
    new mp4_demuxer::BufferStream(mInitData);

  mMetadata = MakeUnique<mp4_demuxer::MP4Metadata>(bufferstream);

  if (!mMetadata->GetNumberTracks(mozilla::TrackInfo::kAudioTrack) &&
      !mMetadata->GetNumberTracks(mozilla::TrackInfo::kVideoTrack)) {
    return InitPromise::CreateAndReject(DemuxerFailureReason::DEMUXER_ERROR, __func__);
  }

  return InitPromise::CreateAndResolve(NS_OK, __func__);
}

bool
MP4Demuxer::HasTrackType(TrackInfo::TrackType aType) const
{
  return !!GetNumberTracks(aType);
}

uint32_t
MP4Demuxer::GetNumberTracks(TrackInfo::TrackType aType) const
{
  return mMetadata->GetNumberTracks(aType);
}

already_AddRefed<MediaTrackDemuxer>
MP4Demuxer::GetTrackDemuxer(TrackInfo::TrackType aType, uint32_t aTrackNumber)
{
  if (mMetadata->GetNumberTracks(aType) <= aTrackNumber) {
    return nullptr;
  }
  UniquePtr<TrackInfo> info = mMetadata->GetTrackInfo(aType, aTrackNumber);
  if (!info) {
    return nullptr;
  }
  FallibleTArray<mp4_demuxer::Index::Indice> indices;
  if (!mMetadata->ReadTrackIndex(indices, info->mTrackId)) {
    return nullptr;
  }
  RefPtr<MP4TrackDemuxer> e = new MP4TrackDemuxer(this, Move(info), indices);
  mDemuxers.AppendElement(e);

  return e.forget();
}

bool
MP4Demuxer::IsSeekable() const
{
  return mMetadata->CanSeek();
}

void
MP4Demuxer::NotifyDataArrived()
{
  for (uint32_t i = 0; i < mDemuxers.Length(); i++) {
    mDemuxers[i]->NotifyDataArrived();
  }
}

void
MP4Demuxer::NotifyDataRemoved()
{
  for (uint32_t i = 0; i < mDemuxers.Length(); i++) {
    mDemuxers[i]->NotifyDataArrived();
  }
}

UniquePtr<EncryptionInfo>
MP4Demuxer::GetCrypto()
{
  const mp4_demuxer::CryptoFile& cryptoFile = mMetadata->Crypto();
  if (!cryptoFile.valid) {
    return nullptr;
  }

  const nsTArray<mp4_demuxer::PsshInfo>& psshs = cryptoFile.pssh;
  nsTArray<uint8_t> initData;
  for (uint32_t i = 0; i < psshs.Length(); i++) {
    initData.AppendElements(psshs[i].data);
  }

  if (initData.IsEmpty()) {
    return nullptr;
  }

  auto crypto = MakeUnique<EncryptionInfo>();
  crypto->AddInitData(NS_LITERAL_STRING("cenc"), Move(initData));

  return crypto;
}

MP4TrackDemuxer::MP4TrackDemuxer(MP4Demuxer* aParent,
                                 UniquePtr<TrackInfo>&& aInfo,
                                 const nsTArray<mp4_demuxer::Index::Indice>& indices)
  : mParent(aParent)
  , mStream(new mp4_demuxer::ResourceStream(mParent->mResource))
  , mInfo(Move(aInfo))
  , mMonitor("MP4TrackDemuxer")
  , mIndex(new mp4_demuxer::Index(indices,
                                  mStream,
                                  mInfo->mTrackId,
                                  mInfo->IsAudio(),
                                  &mMonitor))
  , mIterator(MakeUnique<mp4_demuxer::SampleIterator>(mIndex))
  , mNeedReIndex(true)
{
  EnsureUpToDateIndex(); // Force update of index

  // Collect telemetry from h264 AVCC SPS.
  if (mInfo->GetAsVideoInfo() &&
      (mInfo->mMimeType.EqualsLiteral("video/mp4") ||
       mInfo->mMimeType.EqualsLiteral("video/avc"))) {
    mNeedSPSForTelemetry =
      AccumulateSPSTelemetry(mInfo->GetAsVideoInfo()->mExtraData);
  } else {
    // No SPS to be found.
    mNeedSPSForTelemetry = false;
  }
}

UniquePtr<TrackInfo>
MP4TrackDemuxer::GetInfo() const
{
  return mInfo->Clone();
}

void
MP4TrackDemuxer::EnsureUpToDateIndex()
{
  if (!mNeedReIndex) {
    return;
  }
  AutoPinned<MediaResource> resource(mParent->mResource);
  nsTArray<MediaByteRange> byteRanges;
  nsresult rv = resource->GetCachedRanges(byteRanges);
  if (NS_FAILED(rv)) {
    return;
  }
  MonitorAutoLock mon(mMonitor);
  mIndex->UpdateMoofIndex(byteRanges);
  mNeedReIndex = false;
}

RefPtr<MP4TrackDemuxer::SeekPromise>
MP4TrackDemuxer::Seek(media::TimeUnit aTime)
{
  int64_t seekTime = aTime.ToMicroseconds();
  mQueuedSample = nullptr;

  MonitorAutoLock mon(mMonitor);
  mIterator->Seek(seekTime);

  // Check what time we actually seeked to.
  mQueuedSample = mIterator->GetNext();
  if (mQueuedSample) {
    seekTime = mQueuedSample->mTime;
  }
  SetNextKeyFrameTime();

  return SeekPromise::CreateAndResolve(media::TimeUnit::FromMicroseconds(seekTime), __func__);
}

RefPtr<MP4TrackDemuxer::SamplesPromise>
MP4TrackDemuxer::GetSamples(int32_t aNumSamples)
{
  EnsureUpToDateIndex();
  RefPtr<SamplesHolder> samples = new SamplesHolder;
  if (!aNumSamples) {
    return SamplesPromise::CreateAndReject(DemuxerFailureReason::DEMUXER_ERROR, __func__);
  }

  if (mQueuedSample) {
    samples->mSamples.AppendElement(mQueuedSample);
    mQueuedSample = nullptr;
    aNumSamples--;
  }
  MonitorAutoLock mon(mMonitor);
  RefPtr<MediaRawData> sample;
  while (aNumSamples && (sample = mIterator->GetNext())) {
    samples->mSamples.AppendElement(sample);
    aNumSamples--;
  }

  if (samples->mSamples.IsEmpty()) {
    return SamplesPromise::CreateAndReject(DemuxerFailureReason::END_OF_STREAM, __func__);
  } else {
    UpdateSamples(samples->mSamples);
    return SamplesPromise::CreateAndResolve(samples, __func__);
  }
}

void
MP4TrackDemuxer::SetNextKeyFrameTime()
{
  mNextKeyframeTime.reset();
  mp4_demuxer::Microseconds frameTime = mIterator->GetNextKeyframeTime();
  if (frameTime != -1) {
    mNextKeyframeTime.emplace(
      media::TimeUnit::FromMicroseconds(frameTime));
  }
}

void
MP4TrackDemuxer::Reset()
{
  mQueuedSample = nullptr;
  // TODO, Seek to first frame available, which isn't always 0.
  MonitorAutoLock mon(mMonitor);
  mIterator->Seek(0);
  SetNextKeyFrameTime();
}

void
MP4TrackDemuxer::UpdateSamples(nsTArray<RefPtr<MediaRawData>>& aSamples)
{
  for (size_t i = 0; i < aSamples.Length(); i++) {
    MediaRawData* sample = aSamples[i];
    // Collect telemetry from h264 Annex B SPS.
    if (mNeedSPSForTelemetry && mp4_demuxer::AnnexB::HasSPS(sample)) {
      RefPtr<MediaByteBuffer> extradata =
        mp4_demuxer::AnnexB::ExtractExtraData(sample);
      mNeedSPSForTelemetry = AccumulateSPSTelemetry(extradata);
    }
    if (sample->mCrypto.mValid) {
      nsAutoPtr<MediaRawDataWriter> writer(sample->CreateWriter());
      writer->mCrypto.mMode = mInfo->mCrypto.mMode;
      writer->mCrypto.mIVSize = mInfo->mCrypto.mIVSize;
      writer->mCrypto.mKeyId.AppendElements(mInfo->mCrypto.mKeyId);
    }
    if (mInfo->GetAsVideoInfo()) {
      sample->mExtraData = mInfo->GetAsVideoInfo()->mExtraData;
    }
  }
  if (mNextKeyframeTime.isNothing() ||
      aSamples.LastElement()->mTime >= mNextKeyframeTime.value().ToMicroseconds()) {
    SetNextKeyFrameTime();
  }
}

nsresult
MP4TrackDemuxer::GetNextRandomAccessPoint(media::TimeUnit* aTime)
{
  if (mNextKeyframeTime.isNothing()) {
    // There's no next key frame.
    *aTime =
      media::TimeUnit::FromMicroseconds(std::numeric_limits<int64_t>::max());
  } else {
    *aTime = mNextKeyframeTime.value();
  }
  return NS_OK;
}

RefPtr<MP4TrackDemuxer::SkipAccessPointPromise>
MP4TrackDemuxer::SkipToNextRandomAccessPoint(media::TimeUnit aTimeThreshold)
{
  MonitorAutoLock mon(mMonitor);
  mQueuedSample = nullptr;
  // Loop until we reach the next keyframe after the threshold.
  uint32_t parsed = 0;
  bool found = false;
  RefPtr<MediaRawData> sample;
  while (!found && (sample = mIterator->GetNext())) {
    parsed++;
    if (sample->mKeyframe && sample->mTime >= aTimeThreshold.ToMicroseconds()) {
      found = true;
      mQueuedSample = sample;
    }
  }
  SetNextKeyFrameTime();
  if (found) {
    return SkipAccessPointPromise::CreateAndResolve(parsed, __func__);
  } else {
    SkipFailureHolder failure(DemuxerFailureReason::END_OF_STREAM, parsed);
    return SkipAccessPointPromise::CreateAndReject(Move(failure), __func__);
  }
}

media::TimeIntervals
MP4TrackDemuxer::GetBuffered()
{
  EnsureUpToDateIndex();
  AutoPinned<MediaResource> resource(mParent->mResource);
  nsTArray<MediaByteRange> byteRanges;
  nsresult rv = resource->GetCachedRanges(byteRanges);

  if (NS_FAILED(rv)) {
    return media::TimeIntervals();
  }
  nsTArray<mp4_demuxer::Interval<int64_t>> timeRanges;

  MonitorAutoLock mon(mMonitor);
  mIndex->ConvertByteRangesToTimeRanges(byteRanges, &timeRanges);
  // convert timeRanges.
  media::TimeIntervals ranges = media::TimeIntervals();
  for (size_t i = 0; i < timeRanges.Length(); i++) {
    ranges +=
      media::TimeInterval(media::TimeUnit::FromMicroseconds(timeRanges[i].start),
                          media::TimeUnit::FromMicroseconds(timeRanges[i].end));
  }
  return ranges;
}

void
MP4TrackDemuxer::NotifyDataArrived()
{
  mNeedReIndex = true;
}

void
MP4TrackDemuxer::BreakCycles()
{
  mParent = nullptr;
}

} // namespace mozilla