Tengo la siguiente función y lo que hace es crear un thumb de una imagen original a un tamaño que yo le defino.
Pero... existe un problema, y es que me gustaria que si la imagen original es mas pequeña que el tamaño del thumb final, la expanda a ese tamaño.
Código PHP:
<?php
function makeIcons_MergeCenter($src, $dst, $dstx, $dsty){
//$src = original image location
//$dst = destination image location
//$dstx = user defined width of image
//$dsty = user defined height of image
$allowedExtensions = 'jpg jpeg gif png';
$name = explode(".", $src);
$currentExtensions = $name[count($name)-1];
$extensions = explode(" ", $allowedExtensions);
for($i=0; count($extensions)>$i; $i=$i+1){
if($extensions[$i]==$currentExtensions)
{ $extensionOK=1;
$fileExtension=$extensions[$i];
break; }
}
if($extensionOK){
$size = getImageSize($src);
$width = $size[0];
$height = $size[1];
if($width >= $dstx AND $height >= $dsty){
$proportion_X = $width / $dstx;
$proportion_Y = $height / $dsty;
if($proportion_X > $proportion_Y ){
$proportion = $proportion_Y;
}else{
$proportion = $proportion_X ;
}
$target['width'] = $dstx * $proportion;
$target['height'] = $dsty * $proportion;
$original['diagonal_center'] =
round(sqrt(($width*$width)+($height*$height))/2);
$target['diagonal_center'] =
round(sqrt(($target['width']*$target['width'])+
($target['height']*$target['height']))/2);
$crop = round($original['diagonal_center'] - $target['diagonal_center']);
if($proportion_X < $proportion_Y ){
$target['x'] = 0;
$target['y'] = round((($height/2)*$crop)/$target['diagonal_center']);
}else{
$target['x'] = round((($width/2)*$crop)/$target['diagonal_center']);
$target['y'] = 0;
}
if($fileExtension == "jpg" OR $fileExtension=='jpeg'){
$from = ImageCreateFromJpeg($src);
}elseif ($fileExtension == "gif"){
$from = ImageCreateFromGIF($src);
}elseif ($fileExtension == 'png'){
$from = imageCreateFromPNG($src);
}
$new = ImageCreateTrueColor ($dstx,$dsty);
imagecopyresampled ($new, $from, 0, 0, $target['x'],
$target['y'], $dstx, $dsty, $target['width'], $target['height']);
if($fileExtension == "jpg" OR $fileExtension == 'jpeg'){
imagejpeg($new, $dst, 70);
}elseif ($fileExtension == "gif"){
imagegif($new, $dst);
}elseif ($fileExtension == 'png'){
imagepng($new, $dst);
}
}
}
}
?>
Esa es la funcion. A ver si alguien me puede hechar una mano.
Un saludo y gracias de antemano. 
