ImageSize

				
=**************************************
= Name: ImageSize
= Description:Gets the size of a Gif, JPG or Jpeg file
= By: M B
=
= Inputs:$File=Filename
=
= Returns:Size of the image
=
=This code is copyrighted and has= limited warranties.Please see http://www.Planet-Source-Code.com/vb/scripts/ShowCode.asp?txtCodeId=259&lngWId=6=for details.=**************************************

#!D:\PERL\BIN\PERL.EXE
		
#	Developed by: Merijn Boom	
&imgsize("c:/sample.jpg");
sub imgsize {
 my($file)= shift @_;
 my($ref)=@_ ? shift @_ : "";
 my($x,$y)=(0,0);
	defined($file) && open(STRM, "<$file");
if ($file =~ /\.jpg$/i || $file =~ /\.jpeg$/i) {
 ($x,$y) = &jpegsize(\*STRM);
} elsif($file =~ /\.gif$/i) {
 ($x,$y) = &gifsize(\*STRM);
} else {
 print "$file is not gif, jpg or jpeg file (or has strange name)";
}
close(STRM);
 
 print"$x, $y\n";
 return ($x,$y);
}
###########################################################################
# Subroutine gets the size of the specified GIF
###########################################################################
sub gifsize
{
 my($GIF) = @_;
 if( &istrue($UseNewGifsize) ){
return &NEWgifsize($GIF);
 } else {
return &OLDgifsize($GIF);
 }
}
###########################################################################
# Subroutine gets the size of the specified JPG or JPeG
###########################################################################
sub jpegsize {
		print".jpg\n";
 my($JPEG) = @_;
 my($done)=0;
 my($c1,$c2,$ch,$s,$length, $dummy)=(0,0,0,0,0,0);
 my($a,$b,$c,$d);
 if(defined($JPEG)		&&
 read($JPEG, $c1, 1)	&&
 read($JPEG, $c2, 1)	&&
 ord($c1) == 0xFF		&&
 ord($c2) == 0xD8		){
while (ord($ch) != 0xDA && !$done) {
 # Find next marker (JPEG markers begin with 0xFF)
 # This can hang the program!!
 while (ord($ch) != 0xFF) { return(0,0) unless read($JPEG, $ch, 1); }
 # JPEG markers can be padded with unlimited 0xFF's
 while (ord($ch) == 0xFF) { return(0,0) unless read($JPEG, $ch, 1); }
 # Now, $ch contains the value of the marker.
 if ((ord($ch) >= 0xC0) && (ord($ch) <= 0xC3)) {
	return(0,0) unless read ($JPEG, $dummy, 3);
	return(0,0) unless read($JPEG, $s, 4);
	($a,$b,$c,$d)=unpack("C"x4,$s);
	return ($c<<8|$d, $a<<8|$b );
 } else {
	# We **MUST** skip variables, since FF's within variable names are
	# NOT valid JPEG markers
	return(0,0) unless read ($JPEG, $s, 2);
	($c1, $c2) = unpack("C"x2,$s);
	$length = $c1<<8|$c2;
	last if (!defined($length) || $length < 2);
	read($JPEG, $dummy, $length-2);
 }
}
 }
 return (0,0);
}
sub istrue
{
 my( $val)=@_;
 return (defined($val) && ($val =~ /^y(es)?/i || $val =~ /true/i ));
}
sub OLDgifsize {
 my($GIF) = @_;
 my($type,$a,$b,$c,$d,$s)=(0,0,0,0,0,0);
 if(defined( $GIF )		&&
 read($GIF, $type, 6)	&&
 $type =~ /GIF8[7,9]a/	&&
 read($GIF, $s, 4) == 4	){
($a,$b,$c,$d)=unpack("C"x4,$s);
return ($b<<8|$a,$d<<8|$c);
 }
 return (0,0);
}
# part of NEWgifsize
sub gif_blockskip {
 my ($GIF, $skip, $type) = @_;
 my ($s)=0;
 my ($dummy)='';
 read ($GIF, $dummy, $skip);	# Skip header (if any)
 while (1) {
if (eof ($GIF)) {
 warn "Invalid/Corrupted GIF (at EOF in GIF $type)\n";
 return "";
}
read($GIF, $s, 1);		# Block size
last if ord($s) == 0;	# Block terminator
read ($GIF, $dummy, ord($s));	# Skip data
 }
}
sub NEWgifsize {
 my($GIF) = @_;
 my($cmapsize, $a, $b, $c, $d, $e)=0;
 my($type,$s)=(0,0);
 my($x,$y)=(0,0);
 my($dummy)='';
 return($x,$y) if(!defined $GIF);
 read($GIF, $type, 6);
 if($type !~ /GIF8[7,9]a/ || read($GIF, $s, 7) != 7 ){
warn "Invalid/Corrupted GIF (bad header)\n";
return($x,$y);
 }
 ($e)=unpack("x4 C",$s);
 if ($e & 0x80) {
$cmapsize = 3 * 2**(($e & 0x07) + 1);
if (!read($GIF, $dummy, $cmapsize)) {
 warn "Invalid/Corrupted GIF (global color map too small?)\n";
 return($x,$y);
}
 }
 FINDIMAGE:
 while (1) {
if (eof ($GIF)) {
 warn "Invalid/Corrupted GIF (at EOF w/o Image Descriptors)\n";
 return($x,$y);
}
read($GIF, $s, 1);
($e) = unpack("C", $s);
if ($e == 0x2c) {		# Image Descriptor (GIF87a, GIF89a 20.c.i)
 if (read($GIF, $s, 8) != 8) {
	warn "Invalid/Corrupted GIF (missing image header?)\n";
	return($x,$y);
 }
 ($a,$b,$c,$d)=unpack("x4 C4",$s);
 $x=$b<<8|$a;
 $y=$d<<8|$c;
 return($x,$y);
}
if ($type eq "GIF89a") {
 if ($e == 0x21) {		# Extension Introducer (GIF89a 23.c.i)
	read($GIF, $s, 1);
	($e) = unpack("C", $s);
	if ($e == 0xF9) {	# Graphic Control Extension (GIF89a 23.c.ii)
	 read($GIF, $dummy, 6);	# Skip it
	 next FINDIMAGE;	# Look again for Image Descriptor
	} elsif ($e == 0xFE) {	# Comment Extension (GIF89a 24.c.ii)
	 &gif_blockskip ($GIF, 0, "Comment");
	 next FINDIMAGE;	# Look again for Image Descriptor
	} elsif ($e == 0x01) {	# Plain Text Label (GIF89a 25.c.ii)
	 &gif_blockskip ($GIF, 12, "text data");
	 next FINDIMAGE;	# Look again for Image Descriptor
	} elsif ($e == 0xFF) {	# Application Extension Label (GIF89a 26.c.ii)
	 &gif_blockskip ($GIF, 11, "application data");
	 next FINDIMAGE;	# Look again for Image Descriptor
	} else {
	 printf STDERR "Invalid/Corrupted GIF (Unknown extension %#x)\n", $e;
	 return($x,$y);
	}
 }
 else {
	printf STDERR "Invalid/Corrupted GIF (Unknown code %#x)\n", $e;
	return($x,$y);
 }
}
else {
 warn "Invalid/Corrupted GIF (missing GIF87a Image Descriptor)\n";
 return($x,$y);
}
 }
}