public PNGChunk(byte[] headerBlock, int offset = 8)
{
Length = MyBitConverter.ToInt32(headerBlock, offset, MyBitConverter.Endianness.BigEndian);
ChunkType = MyBitConverter.ToInt32(headerBlock, offset + 4, MyBitConverter.Endianness.BigEndian);
ChunkData = new byte[Length];
Array.Copy(headerBlock, offset + 8, ChunkData, 0, Length);
CRC = MyBitConverter.ToInt32(headerBlock, offset + 8 + Length, MyBitConverter.Endianness.BigEndian);
}