QB Image Processing Pseudocode

leftmost = 15		#Initial value
for y in range(16):	#Loop by rows
	count = 0 	#Count keeps track of the pixel position
	pos = 128 * y + 40 				#Offset to the start of a row
	for x in range(8): 				#Loop now by the column. This keeps track of bytes
		if data[pos] >> 4 > 0: 			#Checking the first pixel in the byte for non-zero value
			if leftmost > count: 		#Update leftmost (if appropriate)
				leftmost = count
				break
		count += 1				#Increment pixel counter
		if data[pos] & 15 > 0: 			#Checking the 2nd pixel in the byte for non-zero value
			if leftmost > count:		#Update leftmost (if appropriate)
				leftmost = count
				break
		count += 1				#Increment pixel counter