&sysread_uint48($RGB, \@rgbz);  # Store RGB in uint64, RGBZ array
&RADIX_SORT(\@rgbz);  # Sort by digits!
$std=$rgbz[0];  # Make first uint64 the STanDard 
$unique=1;      # First one is Always Unique!
for($ii=1; $ii < $num_pix; $ii++)  {
	next  if($rgbz[$ii] == $std);  # Same Old value as last time!
	$unique++;                    # New value, Increment Unique
	$std=$rgbz[$ii];              # Make new THIS the STD
}
printf("%d distinct values\n", $unique);