private static uint ReadPayloadValue(INalUnitReader reader)
{
uint value = 0;
uint b = reader.GetByte(true);
while (b == 0xff)
{
value += 255;
b = reader.GetByte(true);
}
return(value + b);
}
public void Parse(INalUnitReader reader, IResultNodeState resultState)
{
resultState.Name = Name;
uint payloadType = ReadPayloadValue(reader);
resultState.AddAttribute(Attribute.PayloadType, payloadType);
uint payloadSize = ReadPayloadValue(reader);
resultState.AddAttribute(Attribute.PayloadSize, payloadSize);
//skip payload
for (int i = 0; i < payloadSize; i++)
{
reader.GetByte(true);
}
// payload type = (FF)* E5
// payload size = (FF)* 01
// payload = 9C
}
// 7.3.2.1.1 SequenceState parameter set data syntax
public void Parse(INalUnitReader reader, IResultNodeState resultState)
{
// Constraints from 7.4.2.11
resultState.Name = Name;
Profile profileIdc = reader.GetBits(8, Attribute.ProfileIdc, _profileValidator);
reader.GetBits(6); // constraint_set{0-5}_flag
if (reader.GetBits(2) != 0) // reserved_zero_2bits
{
resultState.Invalidate();
return;
}
reader.GetByte(false, Attribute.LevelIdc, 59); // level_idc, Table A-1 - Level limits
uint sequenceParameterSetId = reader.GetExpGolombCoded(Attribute.SequenceParameterSetId, 31);
ISequenceStateBuilder builder = new SequenceStateBuilder(sequenceParameterSetId);
builder.ByteStreamFormat = reader.State.ByteStreamFormat;
builder.ProfileIdc = profileIdc;
if (IsHighProfile(profileIdc))
{
uint chromaFormatIdc = reader.GetExpGolombCoded(Attribute.ChromaFormatIdc, 3); // Table 6-1
builder.ChromaFormatIdc = chromaFormatIdc;
if (chromaFormatIdc == 3)
{
builder.SeparateColourPlaneFlag = reader.GetBit(Attribute.SeparateColorPlaneFlag);
}
builder.BitDepthLumaMinus8 = reader.GetExpGolombCoded(Attribute.BitDepthLumaArraySampleMinus8, 6);
builder.BitDepthChromaMinus8 = reader.GetExpGolombCoded(Attribute.BitDepthChromaArraySampleMinus8, 6);
reader.GetBit(); // qpprime_y_zero_transform_bypass_flag
if (reader.GetBit()) // seq_scaling_matrix_present_flag
{
for (int i = 0; i < ((chromaFormatIdc != 3) ? 8 : 12); i++)
{
if (reader.GetBit()) // seq_scaling_list_present_flag[i]
{
// FIXME: scaling_list() is not implemented!!
resultState.Invalidate();
return;
}
}
}
}
builder.Log2MaxFrameNumMinus4 = reader.GetExpGolombCoded(Attribute.Log2MaxFrameNumMinus4, 28);
DecodePictureOrderCount(reader, builder);
uint maxDpbFramesUpperLimit = (profileIdc == Profile.MultiviewHigh) ? 160U : 16U; //could use the exact maxDpbFrames, but this is easier
builder.MaxNumRefFrames = reader.GetExpGolombCoded(Attribute.MaxNumberReferenceFrames, maxDpbFramesUpperLimit);
reader.GetBit(); // gaps_in_frame_num_value_allowed_flag
builder.PicWidthInMbsMinus1 = reader.GetExpGolombCoded(Attribute.PictureWidthInMacroBlocksMinus1, 543);
builder.PicHeightInMapUnitsMinus1 = reader.GetExpGolombCoded(Attribute.PictureHeightInMapUnitsMinus1, 543);
var frameMbsOnlyFlag = reader.GetBit(Attribute.FrameMbsOnlyFlag);
builder.FrameMbsOnlyFlag = frameMbsOnlyFlag;
if (!frameMbsOnlyFlag)
{
builder.MbAdaptiveFrameFieldFlag = reader.GetBit();
}
bool direct8X8InferenceFlag = reader.GetBit();
builder.Direct8X8InferenceFlag = direct8X8InferenceFlag;
if (!frameMbsOnlyFlag && !direct8X8InferenceFlag)
{
resultState.Invalidate();
return;
}
if (reader.GetBit()) // frame_cropping_flag
{
// TODO: Cropping should not exceed the size of a frame!
reader.GetExpGolombCoded(Attribute.FrameCropLeftOffset, 8703);
reader.GetExpGolombCoded(Attribute.FrameCropRightOffset, 8703);
reader.GetExpGolombCoded(Attribute.FrameCropTopOffset, 8703);
reader.GetExpGolombCoded(Attribute.FrameCropBottomOffset, 8703);
}
if (reader.GetBit()) // vui_parameters_present_flag
{
GetVuiParameters(reader, resultState);
}
if (reader.ShowBits(1) == 1)
{
reader.GetBit(); // rbsp_stop_one_bit (equal to 1)
// trailing zero bits
}
if (resultState.Valid)
{
reader.State.SequenceStates[sequenceParameterSetId] = builder.Build();
}
}
private static void GetVuiParameters(INalUnitReader reader, IResultNodeState resultState)
{
const byte extendedSar = 255; // Extended_SAR
bool aspectRatioInfoPresentFlag = reader.GetBit();
if (aspectRatioInfoPresentFlag) // aspect_ratio_info_present_flag
{
byte aspectRatioIdc = reader.GetByte(false);
if (aspectRatioIdc == extendedSar) // aspect_ratio_idc
{
reader.GetBits(16); // sar_width
reader.GetBits(16); // sar_height
}
}
bool overscanInfoPresentFlag = reader.GetBit();
if (overscanInfoPresentFlag) // overscan_info_present_flag
{
reader.GetBit(); // overscan_appropriate_flag
}
bool videoSignalTypePresentFlag = reader.GetBit();
if (videoSignalTypePresentFlag) // video_signal_type_present_flag
{
reader.GetBits(3); // video_format
reader.GetBit(); // video_full_range_flag
bool colourDescriptionPresentFlag = reader.GetBit();
if (colourDescriptionPresentFlag) // colour_description_present_flag
{
reader.GetByte(false); // colour_primaries
reader.GetByte(false); // transfer_characteristics
reader.GetByte(false); // matrix_coefficients
}
}
bool chromaLocInfoPresentFlag = reader.GetBit();
if (chromaLocInfoPresentFlag) // chroma_loc_info_present_flag
{
reader.GetExpGolombCoded(); // chroma_sample_loc_type_top_field
reader.GetExpGolombCoded(); // chroma_sample_loc_type_bottom_field
}
bool timingInfoPresentFlag = reader.GetBit();
if (timingInfoPresentFlag) // timing_info_present_flag
{
reader.GetBits(32); // num_units_in_tick
reader.GetBits(32); // time_scale
reader.GetBit(); // fixed_frame_rate_flag
}
bool nalHrdParametersPresentFlag = reader.GetBit();
if (nalHrdParametersPresentFlag) //nal_hrd_parameters_present_flag
{
GetHrdParameters(reader, resultState); // hrd_parameters()
}
bool vclHrdParametersPresentFlag = reader.GetBit();
if (vclHrdParametersPresentFlag) // vcl_hrd_parameters_present_flag
{
GetHrdParameters(reader, resultState); // hrd_parameters()
}
if (nalHrdParametersPresentFlag || vclHrdParametersPresentFlag)
{
reader.GetBit(); // low_delay_hrd_flag
}
reader.GetBit(); // pic_struct_present_flag
bool bitstreamRestrictionFlag = reader.GetBit();
if (bitstreamRestrictionFlag) // bitstream_restriction_flag
{
reader.GetBit(); // motion_vectors_over_pic_boundaries_flag
reader.GetExpGolombCoded(); // max_bytes_per_pic_denom
reader.GetExpGolombCoded(); // max_bits_per_mb_denom
reader.GetExpGolombCoded(); // log2_max_mv_length_horizontal
reader.GetExpGolombCoded(); // log2_max_mv_length_vertical
reader.GetExpGolombCoded(); // num_reorder_frames
reader.GetExpGolombCoded(); // max_dec_frame_buffering
}
}