image resize

[gagz]

is there any way to get php to actually physically resize and image? ie make it a thumbnail?

 

[ingernet]

gagz,

Yes, there's a way to do it. I wrote something that would let me upload a file and make a thumbnail of it that was either 60 pixels high or 60 pixels wide, depending on whether it was portrait or landscape.

here's a brief sample of how i did it:

1. in my form, i called the file field "img1." PHP has a bunch of built-in variables that it associates with an uploaded file, like its name and mime type, etc., which are all, thankfully, named things like $img1_name and $img1_type. you can read more about that on the php.net docs.

2. here's the php stuff. i hope it helps:

//create a full path to the newly uploaded file
$mypath = "/path/to/uploaded_file"
$working_file=("$mypath" . "$img1_name"

//write a tmp file using a different function depending on mime type
if ($img1_type=="image/jpeg&quot {
$src_img = imagecreatefromjpeg($working_file);
} elseif ($img1_type=="image/png&quot {
$src_img = imagecreatefrompng($working_file) or die("couldn't create image using imagecreatefrompng"
}

if (($img1_type=="image/jpeg&quot || ($img1_type=="image/png&quot) {
$orig_width = imagesX($src_img);
$orig_height = imagesY($src_img);

//if width is more than height, make width 60 pixels and
//make height proportional
if ($orig_width >= $orig_height) {
$new_w = 60;
$resize_factor = 60/$orig_width;
$new_h = $orig_height * $resize_factor;
} else {
//else use the height and make width proportional
$new_h = 60;
$resize_factor = 60/$orig_height;
$new_w = $orig_width * $resize_factor;
}

$dst_img = imagecreate($new_w,$new_h);
imagecopyresized($dst_img,$src_img,0,0,0,0,$new_w,$new_h,imagesX($src_img),imagesY($src_img));
//make a thumbnail using different functions based on mimetype of original
if ($img1_type=="image/jpeg&quot {
imagejpeg($dst_img, "../thumbnails/$img1_name"
} elseif ($img1_type=="image/png&quot {
imagepng($dst_img, "../thumbnails/$img1_name&quot or die("couldn't use imagepng"
}

echo &quot;<P>thumbnail:<br><a href=../uploaded_images/$img1_name><img src=/thumbnails/$img1_name></a><p>\n&quot;;