Krav til en GIF-fil

• if ( substr ( $filename, -4, 4 ) eq ".gif" ) {

• open ( FILE, $filename );

• my $head; my $gHeadFmt = "A6vvb8CC";

• my $pictDescFmt = "vvvvb8";

• read FILE, $head, 13;

• (my $GIF8xa, $width, $height, my $resFlags, my $bgColor, my $w2h) = unpack $gHeadFmt, $head;

• close FILE;

• $PhotoWidth = $width;

• $PhotoHeight = $height;

• $PhotoSize = $size;

• }