source stegLibrary.tcl

set secret [image create photo -file $argv]
set imgWidth [image width $secret]
set imgHeight [image height $secret] 
set extracted [image create photo \
    -height $imgHeight -width $imgWidth]

canvas .c -height $imgHeight -width [expr {$imgWidth*2}]
grid .c

.c create image 0 0 -image $secret -anchor nw
.c create image $imgWidth 0 -image $extracted -anchor nw   

extractLowBlue $secret $extracted