flags-grid-data is 32x20 grid data 
   1) (R G B, each 8 bit, start from byte 14 of the file, front 13 bytes is header)
   2) data is from top-left to bottom-right, total 639 points, so need 1 extra points? (may copy from last)
   3) the data will send to ambilight by TV internel message (plugin+message)