public void Parse(IMpeg2VideoReader reader, IResultNodeState resultState) { IPictureState pictureState = reader.State.Picture; resultState.Name = Name; // It can occur after the last slice of the previous picture or after a sequence header // or group of pictures header, possible followed by user data and/or extensions. if ((reader.State.LastHeaderName != Slice.Name) && pictureState.Initialized) { resultState.Invalidate(); return; } if (!reader.State.Sequence.Initialized && !reader.State.SeenGop) { reader.InsertReferenceHeaderBeforeStartCode(); } pictureState.Reset(); reader.State.Slice.Reset(); reader.GetBits(10, Attribute.TemporalReference); var pictureCodingType = (PictureCodingType)reader.GetBits(3, Attribute.PictureCodingType, _pictureCodingTypeResultFormatter); pictureState.CodingType = pictureCodingType; reader.GetBits(16, Attribute.VbvDelay); if ((pictureCodingType == PictureCodingType.PType) || (pictureCodingType == PictureCodingType.BType)) { reader.GetFlag(Attribute.FullPelForwardVector); byte forwardFCode = (byte)reader.GetBits(3, Attribute.ForwardFCode); pictureState.ForwardHorizontalFCode = forwardFCode; pictureState.ForwardVerticalFCode = forwardFCode; } if (pictureCodingType == PictureCodingType.BType) { reader.GetFlag(Attribute.FullPelBackwardVector); byte backwardFCode = (byte)reader.GetBits(3, Attribute.BackwardFCode); pictureState.BackwardHorizontalFCode = backwardFCode; pictureState.BackwardVerticalFCode = backwardFCode; } int count = 0; // Sanity check uint maxExtraInformationLength = reader.State.Configuration.PictureHeaderMaxLengthOfExtraInformation; while (reader.ShowBits(1) == 1) { reader.GetBits(1); // ExtraBitPicture reader.GetBits(8); // ExtraInformationPicture if (count++ > maxExtraInformationLength) { resultState.Invalidate(); return; } } }
public void Parse(IMpeg2VideoReader reader, IResultNodeState resultState) { resultState.Name = Name; IMpeg2VideoState state = reader.State; // It can occur after the last slice of a picture or after a sequence header, possible followed by user data and/or extensions if ((state.LastHeaderName != Slice.Name) && (state.LastHeaderName != null) && (!state.Sequence.Initialized || state.SeenGop || state.Picture.Initialized)) { resultState.Invalidate(); return; } if (!reader.State.Sequence.Initialized) { reader.InsertReferenceHeaderBeforeStartCode(); } state.SeenGop = true; state.Picture.Reset(); reader.GetAttribute(_timeCodeAttribute); reader.GetFlag(Attribute.ClosedGop); reader.GetFlag(Attribute.BrokenLink); }