/// <summary>
/// parse an ODS packet which contain the image data
/// </summary>
/// <param name="buffer">raw byte date, starting right after segment</param>
/// <param name="segment">object containing info about the current segment</param>
/// <returns>true if this is a valid new object (neither invalid nor a fragment)</returns>
private static OdsData ParseOds(byte[] buffer, SupSegment segment, bool forceFirst)
{
int objId = BigEndianInt16(buffer, 0); // 16bit object_id
int objVer = buffer[2]; // 16bit object_id nikse - index 2 or 1???
int objSeq = buffer[3]; // 8bit first_in_sequence (0x80),
// last_in_sequence (0x40), 6bits reserved
bool first = ((objSeq & 0x80) == 0x80) || forceFirst;
bool last = (objSeq & 0x40) == 0x40;
var info = new ImageObjectFragment();
if (first)
{
int width = BigEndianInt16(buffer, 7); // object_width
int height = BigEndianInt16(buffer, 9); // object_height
info.ImagePacketSize = segment.Size - 11; // Image packet size (image bytes)
info.ImageBuffer = new byte[info.ImagePacketSize];
Buffer.BlockCopy(buffer, 11, info.ImageBuffer, 0, info.ImagePacketSize);
return new OdsData
{
IsFirst = true,
Size = new Size(width, height),
ObjectId = objId,
ObjectVersion = objVer,
Fragment = info,
Message = "ObjId: " + objId + ", ver: " + objVer + ", seq: first" + (last ? "/" : "") + (last ? "" + "last" : "") + ", width: " + width + ", height: " + height,
};
}
else
{
info.ImagePacketSize = segment.Size - 4;
info.ImageBuffer = new byte[info.ImagePacketSize];
Buffer.BlockCopy(buffer, 4, info.ImageBuffer, 0, info.ImagePacketSize);
return new OdsData
{
IsFirst = false,
ObjectId = objId,
ObjectVersion = objVer,
Fragment = info,
Message = "Continued ObjId: " + objId + ", ver: " + objVer + ", seq: " + (last ? "" + "last" : ""),
};
}
}
