Creating thumbnails using upload

BabeWalls

Hi,
Is it possible to have a php upload page which uploads a full size wallpaper and alos creates a thumnail of it with a specific width and with thb added to the beginning of the file name?

(I have had a look at ImageMagick but it seems confusing, I thought it would be much simpler using a php file)

jc94062

What you'd have to do is upload the full size image as normal and then copy that image to an image called "_thb_name-of-original-image".

You'd then have to resize that new file to say 10% of the original size to make it a thumbnail.

You'll have to look up the functions needed to get the original pixel size, then just do some basic math work to get 10% of that and then use something to resize it.

I had a quick look and it should be possible:

http://www.php.net/manual/en/print/function.imagecopyresized.php

For example.

Its also possible www.hotscripts.com or some other open source site already has code to do something like this.

dracula007

Hello,
I'm not an ImageMagick expert, but usually it's not a good idea to resize images solely with PHP + GD 1.x The GD library prior to 2 doesn't support ImageCopyResampled, and the ImageCopyResized gives bad results.

So this solution solution applies only to PHP + GD 2.x. It get's image from $input_file (for example from upload), and saves the thumbnail in $output_file. It uses JPEG format and it constraints proportions, but it's really easy to use different formats too.

<?
// thumbnail sizes
$thumb_max_width = 100;
$thumb_max_height = 100;
$thumb_quality = 90;

// read image size
$size = getimagesize($input_file);

// read the input file
$input_image = imagecreatefromjpeg($input_file);

// compute ratio
$ratio = min($thumb_max_width,$size[0],$thumb_max_height/$size[1]);

// create output image
$output_image = ImageCreate(round($size[0] $ratio),round($size[1] $ratio));

// resample image
// when using GD 1.x change this to imagecopyresized
imagecopyresampled($output_image, $input_image, 0, 0, 0, 0, round($size[0] $ratio), round($size[1] $ratio), $size[0], $size[1]);

// create output image
imagejpeg($output_image,$output_file,$thumb_quality);
imagedestroy($input_image);
imagedestroy($output_image);
?>

Tomas