'''Aug 28 2005''' [SRIV] After noticing that some of the NOAA enhance satellite images were being delayed around 1-2 hours, I decided to try to enhance the higher resolution black & white images.

This script will download and display the latest North America image, then enhance the image with colors.
Heres what the output looks like: http://server.linuxsys.net/images/latest_eastir_eh.gif compared to NOAA's image http://server.linuxsys.net/images/satimg.jpg .

[RS] Here's a snapshot of the Katrina Category 5 Hurricane (between Florida and N.O.) on 2005-08-28:

[http://mini.net/files/katrina.gif]
----

	# satenhance.tcl 08-28-2005 Steve Redler IV 
	package require Tk
	package require http
	
	canvas .c -width 1000 -height 900
	pack .c
	
	proc colorize {image} {
		# get image sizes
		set width  [image width  $image]
		set height [image height $image]
		
		for {set y 0} {$y < $height} {incr y} {
			puts "row=$y"
			set row {}
			for {set x 0} {$x < $width} {incr x} {
				# save transparency
				lappend trans $x $y [$image transparency get $x $y]
				# compute the new color
				foreach {r g b} [$image get $x $y] break
				if {$r > 254} {
					#white
					lappend row [format #%02x%02x%02x 255 255 255]
					continue
				} elseif {$r > 240} {
					#dkgrey
					lappend row [format #%02x%02x%02x 50 50 50]
					continue
				} elseif {$r > 230} {
					#ltgreen
					lappend row [format #%02x%02x%02x 132 247 128]
					continue
				} elseif {$r > 226} {
					#green
					lappend row [format #%02x%02x%02x 60 214 18]
					continue
				} elseif {$r > 222} {
					#ltpink
					lappend row [format #%02x%02x%02x 249 127 124]
					continue
				} elseif {$r > 218} {
					#pink
					lappend row [format #%02x%02x%02x 255 91 98]
					continue
				} elseif {$r > 214} {
					#ltred
					lappend row [format #%02x%02x%02x 217 0 0]
					continue
				} elseif {$r > 210} {
					#red
					lappend row [format #%02x%02x%02x 150 0 0]
					continue
				} elseif {$r > 205} {
					#dkred
					lappend row [format #%02x%02x%02x 114 0 0]
					continue
				} elseif {$r > 200} {
					#ltble
					lappend row [format #%02x%02x%02x 0 215 230]
					continue
				} elseif {$r > 195} {
					#blue
					lappend row [format #%02x%02x%02x 0 100 170]
					continue
				} elseif {$r > 190} {
					#dkblue
					lappend row [format #%02x%02x%02x 0 11 100]
					continue
				} elseif {$r > 185} {
					#ltyellow
					lappend row [format #%02x%02x%02x 240 240 0]
					continue
				} elseif {$r > 180} {
					#yellow
					lappend row [format #%02x%02x%02x 160 160 0]
					continue
				} elseif {$r > 170} {
					#dkyellow
					lappend row [format #%02x%02x%02x 100 100 0]
					continue
				} else {
					lappend row [format #%02x%02x%02x $r $r $r]
				}
				
			}
			# update the row of the image
			satimage put \{$row\} -to 0 $y
			update
		}
		
		# restore transparency
		foreach {x y t} $trans { $image transparency set $x $y $t }
	}
	
	set imagedata [http::data [http::geturl http://www.ssec.wisc.edu/data/east/latest_eastir.gif]]
	
	
	image create photo satimage -data $imagedata
	.c create image 0 0 -image satimage -tag imgtag -anchor nw
	
	update
	after 100 [colorize satimage]
	update
	# write the result to disk
	satimage write latest_eastir_eh.gif -format gif