unsigned int get_crc32(unsigned char* buffer, unsigned int length, unsigned int seed)
{
  unsigned int crc = seed;
  unsigned int i   = 0;

  while (length > 0)
  {
    crc  = crc_table[buffer[i] ^ (crc >> 24)] ^ (crc << 8);
    length--;
    i++;
  }

  return crc;
}