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<?php
/*
ImageThumb - Creates a thumbnail image from another based on specified sizes

SourceImage - The location of the image in which you want to resize
DestImage - The location to save the thumb, use null if you want to just display to browser
Width - The resized width of the image
Height - The resized height of the image
Type - The image type in which you want to save

Note: The thumb is resized while keeping the aspect ratio, so width and height are not the
absolute width and height.
*/

function ImageThumb($sourceImage, $destImage, $width, $height, $type = "png") {
$type = strtolower($type);
$imageSize = getimagesize($sourceImage);

if($imageSize[0] > $imageSize[1]) {
$newWidth = $width;
$newHeight = $imageSize[1] * ($newWidth / $imageSize[0]);
}
else {
$newHeight = $height;
$newWidth = $imageSize[0] * ($newHeight / $imageSize[1]);
}

switch(image_type_to_mime_type($imageSize[2])) {
case "image/jpeg":
$image = imagecreatefromjpeg($sourceImage);
break;
case "image/gif":
$image = imagecreatefromgif($sourceImage);
break;
case "image/png":
$image = imagecreatefrompng($sourceImage);
break;
default:
$t = image_type_to_mime_type($imageSize[2]);
echo "The file type {$t} is not supported, please use either jpeg, gif, or png";
break;
}

$thumb = imagecreatetruecolor($newWidth, $newHeight);
imagecopyresampled($thumb, $image, 0, 0, 0, 0, $newWidth, $newHeight, $imageSize[0], $imageSize[1]);

switch($type) {
case "jpg":
case "jpeg":
header("Content-type: image/jpeg");
imagejpeg($thumb, $destImage);
break;
case "gif":
header("Content-type: image/gif");
imagegif($thumb, $destImage);
break;
case "png":
header("Content-type: image/png");
imagepng($thumb, $destImage);
break;
default:
echo "The image type {$type} is not supported, please choose another.";
break;
}

imagedestroy($image);
imagedestroy($thumb);
}
?>

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