Posted to tcl by patthoyts at Tue Sep 15 23:14:53 GMT 2009view raw

  1. proc lut {contrast brightness} {
  2. variable map_values
  3. set image {}
  4. foreach col $map_values {
  5. set row {}
  6. foreach val $col {
  7. set v [expr {int($val * $contrast + $brightness)}]
  8. if {$v > 255} { set v 255}
  9. #lappend row [lindex $lut $v]
  10. lappend row [format "#%02x0000" $v]
  11. #lappend row [format "#%02x%02x%02x" $v $v $v]
  12. }
  13. lappend image $row
  14. }
  15. mapimage0 put $image
  16. }