C++ MediaResource::GetLength方法代码示例

nsresult GStreamerReader::GetBuffered(dom::TimeRanges* aBuffered,
                                      int64_t aStartTime)
{
    if (!mInfo.HasValidMedia()) {
        return NS_OK;
    }

#if GST_VERSION_MAJOR == 0
    GstFormat format = GST_FORMAT_TIME;
#endif
    MediaResource* resource = mDecoder->GetResource();
    nsTArray<MediaByteRange> ranges;
    resource->GetCachedRanges(ranges);

    if (resource->IsDataCachedToEndOfResource(0)) {
        /* fast path for local or completely cached files */
        gint64 duration = 0;

        {
            ReentrantMonitorAutoEnter mon(mDecoder->GetReentrantMonitor());
            duration = mDecoder->GetMediaDuration();
        }

        double end = (double) duration / GST_MSECOND;
        LOG(PR_LOG_DEBUG, "complete range [0, %f] for [0, %li]",
            end, resource->GetLength());
        aBuffered->Add(0, end);
        return NS_OK;
    }

    for(uint32_t index = 0; index < ranges.Length(); index++) {
        int64_t startOffset = ranges[index].mStart;
        int64_t endOffset = ranges[index].mEnd;
        gint64 startTime, endTime;

#if GST_VERSION_MAJOR >= 1
        if (!gst_element_query_convert(GST_ELEMENT(mPlayBin), GST_FORMAT_BYTES,
                                       startOffset, GST_FORMAT_TIME, &startTime))
            continue;
        if (!gst_element_query_convert(GST_ELEMENT(mPlayBin), GST_FORMAT_BYTES,
                                       endOffset, GST_FORMAT_TIME, &endTime))
            continue;
#else
        if (!gst_element_query_convert(GST_ELEMENT(mPlayBin), GST_FORMAT_BYTES,
                                       startOffset, &format, &startTime) || format != GST_FORMAT_TIME)
            continue;
        if (!gst_element_query_convert(GST_ELEMENT(mPlayBin), GST_FORMAT_BYTES,
                                       endOffset, &format, &endTime) || format != GST_FORMAT_TIME)
            continue;
#endif

        double start = (double) GST_TIME_AS_USECONDS (startTime) / GST_MSECOND;
        double end = (double) GST_TIME_AS_USECONDS (endTime) / GST_MSECOND;
        LOG(PR_LOG_DEBUG, "adding range [%f, %f] for [%li %li] size %li",
            start, end, startOffset, endOffset, resource->GetLength());
        aBuffered->Add(start, end);
    }

    return NS_OK;
}

nsresult GStreamerReader::GetBuffered(TimeRanges* aBuffered,
                                      int64_t aStartTime)
{
  if (!mInfo.mHasVideo && !mInfo.mHasAudio) {
    return NS_OK;
  }

  GstFormat format = GST_FORMAT_TIME;
  MediaResource* resource = mDecoder->GetResource();
  nsTArray<MediaByteRange> ranges;
  resource->GetCachedRanges(ranges);

  if (mDecoder->OnStateMachineThread())
    /* Report the position from here while buffering as we can't report it from
     * the gstreamer threads that are actually reading from the resource
     */
    NotifyBytesConsumed();

  if (resource->IsDataCachedToEndOfResource(0)) {
    /* fast path for local or completely cached files */
    gint64 duration = 0;

    duration = QueryDuration();
    double end = (double) duration / GST_MSECOND;
    LOG(PR_LOG_DEBUG, ("complete range [0, %f] for [0, %li]",
          end, resource->GetLength()));
    aBuffered->Add(0, end);
    return NS_OK;
  }

  for(uint32_t index = 0; index < ranges.Length(); index++) {
    int64_t startOffset = ranges[index].mStart;
    int64_t endOffset = ranges[index].mEnd;
    gint64 startTime, endTime;

    if (!gst_element_query_convert(GST_ELEMENT(mPlayBin), GST_FORMAT_BYTES,
      startOffset, &format, &startTime) || format != GST_FORMAT_TIME)
      continue;
    if (!gst_element_query_convert(GST_ELEMENT(mPlayBin), GST_FORMAT_BYTES,
      endOffset, &format, &endTime) || format != GST_FORMAT_TIME)
      continue;

    double start = (double) GST_TIME_AS_USECONDS (startTime) / GST_MSECOND;
    double end = (double) GST_TIME_AS_USECONDS (endTime) / GST_MSECOND;
    LOG(PR_LOG_DEBUG, ("adding range [%f, %f] for [%li %li] size %li",
          start, end, startOffset, endOffset, resource->GetLength()));
    aBuffered->Add(start, end);
  }

  return NS_OK;
}

gboolean GStreamerReader::SeekData(GstAppSrc* aSrc, guint64 aOffset)
{
  aOffset += mDataOffset;

  ReentrantMonitorAutoEnter mon(mGstThreadsMonitor);
  MediaResource* resource = mDecoder->GetResource();
  int64_t resourceLength = resource->GetLength();

  if (gst_app_src_get_size(mSource) == -1) {
    /* It's possible that we didn't know the length when we initialized mSource
     * but maybe we do now
     */
    gst_app_src_set_size(mSource, GetDataLength());
  }

  nsresult rv = NS_ERROR_FAILURE;
  if (aOffset < static_cast<guint64>(resourceLength)) {
    rv = resource->Seek(SEEK_SET, aOffset);
  }

  if (NS_FAILED(rv)) {
    LOG(PR_LOG_ERROR, "seek at %lu failed", aOffset);
  } else {
    MOZ_ASSERT(aOffset == static_cast<guint64>(resource->Tell()));
  }

  return NS_SUCCEEDED(rv);
}

void GStreamerReader::PlayBinSourceSetup(GstAppSrc* aSource)
{
  mSource = GST_APP_SRC(aSource);
  gst_app_src_set_callbacks(mSource, &mSrcCallbacks, (gpointer) this, nullptr);
  MediaResource* resource = mDecoder->GetResource();

  /* do a short read to trigger a network request so that GetLength() below
   * returns something meaningful and not -1
   */
  char buf[512];
  unsigned int size = 0;
  resource->Read(buf, sizeof(buf), &size);
  resource->Seek(SEEK_SET, 0);

  /* now we should have a length */
  int64_t resourceLength = resource->GetLength();
  gst_app_src_set_size(mSource, resourceLength);
  if (resource->IsDataCachedToEndOfResource(0) ||
      (resourceLength != -1 && resourceLength <= SHORT_FILE_SIZE)) {
    /* let the demuxer work in pull mode for local files (or very short files)
     * so that we get optimal seeking accuracy/performance
     */
    LOG(PR_LOG_DEBUG, ("configuring random access, len %lld", resourceLength));
    gst_app_src_set_stream_type(mSource, GST_APP_STREAM_TYPE_RANDOM_ACCESS);
  } else {
    /* make the demuxer work in push mode so that seeking is kept to a minimum
     */
    LOG(PR_LOG_DEBUG, ("configuring push mode, len %lld", resourceLength));
    gst_app_src_set_stream_type(mSource, GST_APP_STREAM_TYPE_SEEKABLE);
  }
}

gboolean nsGStreamerReader::SeekData(GstAppSrc *aSrc, guint64 aOffset)
{
  ReentrantMonitorAutoEnter mon(mGstThreadsMonitor);
  MediaResource* resource = mDecoder->GetResource();

  if (gst_app_src_get_size(mSource) == -1)
    /* It's possible that we didn't know the length when we initialized mSource
     * but maybe we do now
     */
    gst_app_src_set_size(mSource, resource->GetLength());

  nsresult rv = NS_ERROR_FAILURE;
  if (aOffset < resource->GetLength())
    rv = resource->Seek(SEEK_SET, aOffset);

  if (NS_SUCCEEDED(rv))
    mByteOffset = mLastReportedByteOffset = aOffset;
  else
    LOG(PR_LOG_ERROR, ("seek at %lu failed", aOffset));

  return NS_SUCCEEDED(rv);
}

nsresult MediaOmxReader::GetBuffered(mozilla::dom::TimeRanges* aBuffered, int64_t aStartTime)
{
  if (!mOmxDecoder.get())
    return NS_OK;

  MediaResource* stream = mOmxDecoder->GetResource();

  int64_t durationUs = 0;
  mOmxDecoder->GetDuration(&durationUs);

  // Nothing to cache if the media takes 0us to play.
  if (!durationUs)
    return NS_OK;

  // Special case completely cached files.  This also handles local files.
  if (stream->IsDataCachedToEndOfResource(0)) {
    aBuffered->Add(0, durationUs);
    return NS_OK;
  }

  int64_t totalBytes = stream->GetLength();

  // If we can't determine the total size, pretend that we have nothing
  // buffered. This will put us in a state of eternally-low-on-undecoded-data
  // which is not get, but about the best we can do.
  if (totalBytes == -1)
    return NS_OK;

  int64_t startOffset = stream->GetNextCachedData(0);
  while (startOffset >= 0) {
    int64_t endOffset = stream->GetCachedDataEnd(startOffset);
    // Bytes [startOffset..endOffset] are cached.
    NS_ASSERTION(startOffset >= 0, "Integer underflow in GetBuffered");
    NS_ASSERTION(endOffset >= 0, "Integer underflow in GetBuffered");

    uint64_t startUs = BytesToTime(startOffset, totalBytes, durationUs);
    uint64_t endUs = BytesToTime(endOffset, totalBytes, durationUs);
    if (startUs != endUs) {
      aBuffered->Add((double)startUs / USECS_PER_S, (double)endUs / USECS_PER_S);
    }
    startOffset = stream->GetNextCachedData(endOffset);
  }
  return NS_OK;
}

void nsGStreamerReader::PlayBinSourceSetup(GstAppSrc *aSource)
{
  mSource = GST_APP_SRC(aSource);
  gst_app_src_set_callbacks(mSource, &mSrcCallbacks, (gpointer) this, NULL);
  MediaResource* resource = mDecoder->GetResource();
  int64_t len = resource->GetLength();
  gst_app_src_set_size(mSource, len);
  if (resource->IsDataCachedToEndOfResource(0) ||
      (len != -1 && len <= SHORT_FILE_SIZE)) {
    /* let the demuxer work in pull mode for local files (or very short files)
     * so that we get optimal seeking accuracy/performance
     */
    LOG(PR_LOG_ERROR, ("configuring random access"));
    gst_app_src_set_stream_type(mSource, GST_APP_STREAM_TYPE_RANDOM_ACCESS);
  } else {
    /* make the demuxer work in push mode so that seeking is kept to a minimum
     */
    gst_app_src_set_stream_type(mSource, GST_APP_STREAM_TYPE_SEEKABLE);
  }
}

nsresult RawReader::ReadMetadata(MediaInfo* aInfo,
                                 MetadataTags** aTags)
{
  NS_ASSERTION(mDecoder->OnDecodeThread(),
               "Should be on decode thread.");

  MediaResource* resource = mDecoder->GetResource();
  NS_ASSERTION(resource, "Decoder has no media resource");

  if (!ReadFromResource(resource, 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 = resource->GetLength();
  if (length != -1) {
    ReentrantMonitorAutoEnter autoMonitor(mDecoder->GetReentrantMonitor());
    mDecoder->SetMediaDuration(USECS_PER_S *
                                      (length - sizeof(RawVideoHeader)) /
                                      (mFrameSize * mFrameRate));
  }

  *aInfo = mInfo;

  *aTags = nullptr;

  return NS_OK;
}