Posted by Tom Rogers on 03/24/05 02:50

Hi,

Wednesday, March 23, 2005, 11:30:53 PM, you wrote:
RA> Hi,
RA> I found this beautiful piece of code on the php site which make a
RA> proportional thumbnail, problem is its only working with JPEG files...and
RA> not with GIFs, can someone please help me convert it to GIF too?

RA> I tried but got a bit confused as there are no functions that are equal to
RA> "imagecreatetruecolor" that is in the below script.
RA> The below script works perfectly for jpgs:

Here is a function I use for scaling that you can use as an example,it
also handles transparent gifs.

You can set $x or $y leaving the other at 0 to maintain aspect ratio
or set both to force a fixed box.


function Scale($input,$out,$x,$y){
$info = getimagesize($input);
$width = $info[0];
$height = $info[1];
$colors = array();
if($width > 0 && $height > 0){
if($x > 0){
$w2 = $x;
if($width > $w2){
$scale = $width/$w2;
$h2 = intval($height/$scale);
}else{
$scale = $w2/$width;
$h2 = intval($height * $scale);
}
}elseif($y > 0){
$h2 = $y;
if($height > $h2){
$scale = $height/$h2;
$w2 = intval($width/$scale);
}else{
$scale = $sw2/$height;
$w2 = intval($width * $scale);
}
}
switch($info[2]){
case 1:
$im = ImageCreateFromGif($input);
$t = ImageColorTransparent($im);
$itype = "gif";
if($t != -1){
$colors = imagecolorsforindex($im, $t);
}
$im2 = ImageCreate($w2,$h2);
break;
case 2:
$itype = "jpeg";
$im = ImageCreateFromJpeg($input);
$im2 = ImageCreateTrueColor($w2,$h2);
break;
case 3:
$itype = "png";
$im = ImageCreateFromPng($input);
$t = ImageColorTransparent($im);
if($t != -1){
$colors = imagecolorsforindex($im, $t);
}
$im2 = ImageCreateTrueColor($w2,$h2);
break;
default:
return;
break;
}
if(count($colors) > 0){
$transp = ImageColorAllocate($im2, $colors["red"],$colors["green"], $colors["blue"]);
}
imagecopyresampled($im2, $im, 0, 0, 0, 0, $w2, $h2, $width, $height);
if(count($colors) > 0){
ImageColorTransparent($im2,$transp);
}
if(eregi("\.gif$",$out)){
ImageGif($im2,$out);
}elseif(eregi("\.jpe?g",$out)){
ImageJpeg($im2,$out,90);
}elseif(eregi("\.png$",$out)){
ImagePng($im2,$out,20);
}
}
}




--
regards,
Tom

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