Method parseDVBSubtitleSegment

YUViewLib/src/parser/Subtitles/SubtitleDVB.cpp:539–607

{

std::tuple<size_t, std::string> dvb::parseDVBSubtitleSegment(ByteVector &              data,
                                                             std::shared_ptr<TreeItem> parent)
{
  // Use the given tree item. If it is not set, use the nalUnitMode (if active).
  // We don't set data (a name) for this item yet.
  // We want to parse the item and then set a good description.
  QString specificDescription;
  if (!parent)
    return {};

  // Create a sub byte parser to access the bits
  SubByteReaderLogging reader(data, parent, "subtitling_segment()");
  if (data.size() < 6)
    throw std::logic_error("The subtitling_segment header must have at least six byte");

  reader.readBits("sync_byte", 8, Options().withCheckEqualTo(15));

  unsigned    segment_type;
  std::string segment_type_name;
  {
    Options opt;
    for (int i = 0; i < 16; i++)
      opt.meaningMap[i] = "reserved for future use";
    opt.meaningMap[16] = "page composition segment";
    opt.meaningMap[17] = "region composition segment";
    opt.meaningMap[18] = "CLUT definition segment";
    opt.meaningMap[19] = "object data segment";
    opt.meaningMap[20] = "display definition segment";
    opt.meaningMap[21] = "disparity signalling segment";
    opt.meaningMap[22] = "alternative_CLUT_segment";
    for (int i = 23; i <= 127; i++)
      opt.meaningMap[i] = "reserved for future use";
    opt.meaningMap[128] = "end of display set segment";
    for (int i = 129; i < 254; i++)
      opt.meaningMap[i] = "private data";
    opt.meaningMap[255] = "stuffing";

    segment_type      = reader.readBits("segment_type", 8, opt);
    segment_type_name = opt.meaningMap[segment_type];
  }

  reader.readBits("page_id", 16);

  auto minSegmentLength = int64_t(data.size() - 6);
  auto segment_length =
      reader.readBits("segment_length", 16, Options().withCheckGreater(minSegmentLength));

  if (segment_type == 0x10)
    parsePageCompositionSegment(reader, segment_length);
  else if (segment_type == 0x11)
    parseRegionCompositionSegment(reader, segment_length);
  else if (segment_type == 0x12)
    parseCLUTDefinitionSegment(reader, segment_length);
  else if (segment_type == 0x13)
    parseObjectDataSegment(reader, segment_length);
  else if (segment_type == 0x14)
    parseDisplayDefinitionSegment(reader);
  else if (segment_type == 0x15)