Thumbnails with PHP

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Hi there,

at present I'm developing a website for a photographer. Currently I'm
using PHPThumb ( /) to create thumbnails
resp. to trim the uploaded photos. The problem is that I have to
define a fixed upload format. Therefore it's only possible to create
horizontal images but no vertical images.

In detail my clients expectations are as follows:

- If he uploads a horizontal image it'll get cropped to a certain
size, e.g. 800p x 600 pixel.
- If he uploads a vertical image the image will cropped with a height
of 600 pixel, centered in a 800 pixel width frame. Than that frame
should be filled black.

I'm not really sure how to realize that. Any suggestions? Thank you in


Re: Thumbnails with PHP

El 24/11/2011 10:51, Niels Lange escribió/wrote:
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I've never used that library but here's the first example I could find
in their manual:


require_once 'path/to/';

      $thumb = PhpThumbFactory::create('/path/to/image.jpg');
catch (Exception $e)
      // handle error here however you'd like

$thumb->resize(100, 100);


So it's pretty obvious that the resize() method accepts a bounding box
size when you call it. You don't have to define a fixed size as you
claim. The same seems to happen with the other methods.

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Do you mean that horizontal images are cropped and vertical images are
resized? From the name (there's no further documentation as far as I
see) it seems that the getCurrentDimensions() method returns the image
size. An image is horizontal if width/height is greater than 1. Use that
to write a conditional that calls either crop() or resize().

-- - Álvaro G. Vicario - Burgos, Spain
-- Mi sitio sobre programación web:
-- Mi web de humor satinado:

Re: Thumbnails with PHP

Niels Lange wrote:
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some code may help you  - this uses the GD library.
You will have too rejig the logic to get the size YOU want.
Also be aware that for large images, this is pretty CPU intensive.
Likewise, there are some potential issues with te GD library not being
re-entrant.. simultaneous production of images MAY have caused some
problems on a busy site.
If you can bear it, its probably better to use code like this ONCE when
UPLOADING the image to generate a thumbnail.

include('shoplib.php'); // contains database access stuff..
open_database(); // ready to check
$id=$_GET['id']; // call as thumbnail.php?id=2395 or whatever
* extract pictre sa BLOB from database
$query="select picture from product where id='".$id."'";
if(($result>0) && (($rows=mysql_numrows($result)) == 1)) //got some data
else die();
if ($name="") die();

// now to shrink the picture..
// GD lib handles nearly all image types
// get sizes
// our thumbnails are 100px wide..dont care about the height so scale as
// we DO care about the height now, so if the height is more than 70px,
scale that
// make empty new wotsit.
header("Content-Type: image/jpeg");
imagejpeg( $thumbnail,null,75); ?>
?> // and remmove ANY trailing whitespace after this..

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