Keith Vetter : 2006-09-06
proc bmpsize {fname} {
set fin [open $fname r]
fconfigure $fin -translation binary
set sig [read $fin 2]
if {$sig ne "BM"} {
close $fin
error "$fname is not a BMP file"
}
seek $fin 14 ;# Past 3 integer header fields
binary scan [read $fin 4] i width
binary scan [read $fin 4] i height
close $fin
return [list $width $height]
}For more BMP file format details, see BMP Dump.
see also Reading GIF image dimensions, Reading PNG image dimensions, Reading JPEG image dimensions.