gecko-dev/dom/media/raw/RawReader.cpp

/* -*- 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/. */

#include "MediaDecoderStateMachine.h"
#include "AbstractMediaDecoder.h"
#include "RawReader.h"
#include "RawDecoder.h"
#include "VideoUtils.h"
#include "nsISeekableStream.h"
#include "gfx2DGlue.h"
#include "mozilla/UniquePtr.h"

using namespace mozilla;
using namespace mozilla::media;

RawReader::RawReader(AbstractMediaDecoder* aDecoder)
  : MediaDecoderReader(aDecoder),
    mCurrentFrame(0), mFrameSize(0), mResource(aDecoder->GetResource())
{
  MOZ_COUNT_CTOR(RawReader);
}

RawReader::~RawReader()
{
  MOZ_COUNT_DTOR(RawReader);
}

nsresult RawReader::ResetDecode()
{
  mCurrentFrame = 0;
  return MediaDecoderReader::ResetDecode();
}

nsresult RawReader::ReadMetadata(MediaInfo* aInfo,
                                 MetadataTags** aTags)
{
  MOZ_ASSERT(OnTaskQueue());

  if (!ReadFromResource(reinterpret_cast<uint8_t*>(&mMetadata),
                        sizeof(mMetadata)))
    return NS_ERROR_FAILURE;

  // Validate the header
  if (!(mMetadata.headerPacketID == 0 /* Packet ID of 0 for the header*/ &&
        mMetadata.codecID == RAW_ID /* "YUV" */ &&
        mMetadata.majorVersion == 0 &&
        mMetadata.minorVersion == 1))
    return NS_ERROR_FAILURE;

  CheckedUint32 dummy = CheckedUint32(static_cast<uint32_t>(mMetadata.frameWidth)) *
                          static_cast<uint32_t>(mMetadata.frameHeight);
  NS_ENSURE_TRUE(dummy.isValid(), NS_ERROR_FAILURE);

  if (mMetadata.aspectDenominator == 0 ||
      mMetadata.framerateDenominator == 0)
    return NS_ERROR_FAILURE; // Invalid data

  // Determine and verify frame display size.
  float pixelAspectRatio = static_cast<float>(mMetadata.aspectNumerator) /
                            mMetadata.aspectDenominator;
  nsIntSize display(mMetadata.frameWidth, mMetadata.frameHeight);
  ScaleDisplayByAspectRatio(display, pixelAspectRatio);
  mPicture = nsIntRect(0, 0, mMetadata.frameWidth, mMetadata.frameHeight);
  nsIntSize frameSize(mMetadata.frameWidth, mMetadata.frameHeight);
  if (!IsValidVideoRegion(frameSize, mPicture, display)) {
    // Video track's frame sizes will overflow. Fail.
    return NS_ERROR_FAILURE;
  }

  mInfo.mVideo.mDisplay = display;

  mFrameRate = static_cast<float>(mMetadata.framerateNumerator) /
               mMetadata.framerateDenominator;

  // Make some sanity checks
  if (mFrameRate > 45 ||
      mFrameRate == 0 ||
      pixelAspectRatio == 0 ||
      mMetadata.frameWidth > 2000 ||
      mMetadata.frameHeight > 2000 ||
      mMetadata.chromaChannelBpp != 4 ||
      mMetadata.lumaChannelBpp != 8 ||
      mMetadata.colorspace != 1 /* 4:2:0 */)
    return NS_ERROR_FAILURE;

  mFrameSize = mMetadata.frameWidth * mMetadata.frameHeight *
    (mMetadata.lumaChannelBpp + mMetadata.chromaChannelBpp) / 8.0 +
    sizeof(RawPacketHeader);

  int64_t length = mResource.GetLength();
  if (length != -1) {
    mInfo.mMetadataDuration.emplace(TimeUnit::FromSeconds((length - sizeof(RawVideoHeader)) /
                                                          (mFrameSize * mFrameRate)));
  }

  *aInfo = mInfo;

  *aTags = nullptr;

  return NS_OK;
}

 bool RawReader::DecodeAudioData()
{
  MOZ_ASSERT(OnTaskQueue());
  return false;
}

// Helper method that either reads until it gets aLength bytes
// or returns false
bool RawReader::ReadFromResource(uint8_t* aBuf, uint32_t aLength)
{
  uint32_t bytesRead = 0;
  nsresult rv;

  rv = mResource.Read(reinterpret_cast<char*>(aBuf), aLength, &bytesRead);
  NS_ENSURE_SUCCESS(rv, false);
  if (bytesRead == 0) {
    return false;
  }

  return true;
}

bool RawReader::DecodeVideoFrame(bool &aKeyframeSkip,
                                     int64_t aTimeThreshold)
{
  MOZ_ASSERT(OnTaskQueue());

  // Record number of frames decoded and parsed. Automatically update the
  // stats counters using the AutoNotifyDecoded stack-based class.
  AbstractMediaDecoder::AutoNotifyDecoded a(mDecoder);

  if (!mFrameSize)
    return false; // Metadata read failed.  We should refuse to play.

  int64_t currentFrameTime = USECS_PER_S * mCurrentFrame / mFrameRate;
  uint32_t length = mFrameSize - sizeof(RawPacketHeader);

  auto buffer = MakeUnique<uint8_t[]>(length);

  // We're always decoding one frame when called
  while(true) {
    RawPacketHeader header;

    // Read in a packet header and validate
    if (!(ReadFromResource(reinterpret_cast<uint8_t*>(&header),
                           sizeof(header))) ||
        !(header.packetID == 0xFF && header.codecID == RAW_ID /* "YUV" */)) {
      return false;
    }

    if (!ReadFromResource(buffer.get(), length)) {
      return false;
    }

    a.mParsed++;

    if (currentFrameTime >= aTimeThreshold)
      break;

    mCurrentFrame++;
    currentFrameTime += static_cast<double>(USECS_PER_S) / mFrameRate;
  }

  VideoData::YCbCrBuffer b;
  b.mPlanes[0].mData = buffer.get();
  b.mPlanes[0].mStride = mMetadata.frameWidth * mMetadata.lumaChannelBpp / 8.0;
  b.mPlanes[0].mHeight = mMetadata.frameHeight;
  b.mPlanes[0].mWidth = mMetadata.frameWidth;
  b.mPlanes[0].mOffset = b.mPlanes[0].mSkip = 0;

  uint32_t cbcrStride = mMetadata.frameWidth * mMetadata.chromaChannelBpp / 8.0;

  b.mPlanes[1].mData = buffer.get() + mMetadata.frameHeight * b.mPlanes[0].mStride;
  b.mPlanes[1].mStride = cbcrStride;
  b.mPlanes[1].mHeight = mMetadata.frameHeight / 2;
  b.mPlanes[1].mWidth = mMetadata.frameWidth / 2;
  b.mPlanes[1].mOffset = b.mPlanes[1].mSkip = 0;

  b.mPlanes[2].mData = b.mPlanes[1].mData + mMetadata.frameHeight * cbcrStride / 2;
  b.mPlanes[2].mStride = cbcrStride;
  b.mPlanes[2].mHeight = mMetadata.frameHeight / 2;
  b.mPlanes[2].mWidth = mMetadata.frameWidth / 2;
  b.mPlanes[2].mOffset = b.mPlanes[2].mSkip = 0;

  RefPtr<VideoData> v = VideoData::Create(mInfo.mVideo,
                                            mDecoder->GetImageContainer(),
                                            -1,
                                            currentFrameTime,
                                            (USECS_PER_S / mFrameRate),
                                            b,
                                            1, // In raw video every frame is a keyframe
                                            -1,
                                            mPicture);
  if (!v)
    return false;

  mVideoQueue.Push(v);
  mCurrentFrame++;
  a.mDecoded++;

  return true;
}

RefPtr<MediaDecoderReader::SeekPromise>
RawReader::Seek(SeekTarget aTarget, int64_t aEndTime)
{
  MOZ_ASSERT(OnTaskQueue());

  uint32_t frame = mCurrentFrame;
  if (aTarget.GetTime().ToMicroseconds() >= UINT_MAX)
    return SeekPromise::CreateAndReject(NS_ERROR_FAILURE, __func__);
  mCurrentFrame = aTarget.GetTime().ToMicroseconds() * mFrameRate / USECS_PER_S;

  CheckedUint32 offset = CheckedUint32(mCurrentFrame) * mFrameSize;
  offset += sizeof(RawVideoHeader);
  NS_ENSURE_TRUE(offset.isValid(), SeekPromise::CreateAndReject(NS_ERROR_FAILURE, __func__));

  nsresult rv = mResource.Seek(nsISeekableStream::NS_SEEK_SET, offset.value());
  NS_ENSURE_SUCCESS(rv, SeekPromise::CreateAndReject(rv, __func__));

  mVideoQueue.Reset();
  RefPtr<SeekPromise::Private> p = new SeekPromise::Private(__func__);
  RefPtr<RawReader> self = this;
  InvokeUntil([self] () {
    MOZ_ASSERT(self->OnTaskQueue());
    NS_ENSURE_TRUE(!self->mShutdown, false);
    bool skip = false;
    return self->DecodeVideoFrame(skip, 0);
  }, [self, aTarget] () {
    MOZ_ASSERT(self->OnTaskQueue());
    return self->mVideoQueue.Peek() &&
           self->mVideoQueue.Peek()->GetEndTime() >= aTarget.GetTime().ToMicroseconds();
  })->Then(OwnerThread(), __func__, [self, p, aTarget] () {
    while (self->mVideoQueue.GetSize() >= 2) {
      RefPtr<VideoData> releaseMe = self->mVideoQueue.PopFront();
    }
    p->Resolve(aTarget.GetTime(), __func__);
  }, [self, p, frame] {
    self->mCurrentFrame = frame;
    self->mVideoQueue.Reset();
    p->Reject(NS_ERROR_FAILURE, __func__);
  });

  return p.forget();
}

media::TimeIntervals RawReader::GetBuffered()
{
  MOZ_ASSERT(OnTaskQueue());
  return media::TimeIntervals();
}