Now that we have a form to upload the image and are able to specify how we want to resize it, we will have to write the actual code for resizing. All we need to do is use the code from the previous examples and combine it all together, to get the following result:

As you can see in the example, we use a simple if-then-else structure to check all the resizing options, and you will probably recognize most of the code from the previous examples.

All that's left to do is resize the image, and then display it, using the following standard code:

And that's all there is to it. We've now got a fully functional online image resizer, which can be used to resize almost any kind of image.

Click here to view a live demo of the image resizer, and click here to view the complete source code.

Let's have a look at another interesting use of PHP's image functions: watermarking images on the fly.

This article was posted on Monday, August 14th, 2006 at 4:44 pm. You can follow any responses to this article through the RSS 2.0 feed. You can leave a response, or trackback from your own site.

5 Responses to “Image manipulation with PHP & the GD library, Part 2”

1. vish Says:
   August 19th, 2006 at 12:55 pm

   Hi
   i want to resample an image to half its original size but there are not properly done
   using the following code so please help me for solving the code :

   0) {
   $row = mysql_fetch_array ($result);
   $percent = 0.5; //ex

   $image_type = $row[”image_type”];
   $image = $row[”image”];
   $image_name = $row[”image_name”];

   header(’Content-type: $image_type’);

   // Get new dimensions
   $width = imagesx($image);
   $height = imagesx($image);

   $new_width = $width * $percent;
   $new_height = $height * $percent;

   // Resample
   $image_p = imagecreatetruecolor($new_width,$new_height);
   $imagecopyresampled($image_p, $image, 0, 0, 0, 0, $new_width, $new_height, $width, $height);
   // Output
   header(’Content-type: image/jpeg’);
   imagejpeg($image_p);

   Regards ,
   vish

   }
   ?>

2. Harry D Says:
   August 23rd, 2006 at 9:51 am

   Hi vish,

   while watching your code I found header(’Content-type: $image_type’); and header(’Content-type: image/jpeg’);.
   You can only send one header at once, not two. Just use the last one to make sure everything gets done before you put the resized image on screen.

   Then, if you need to resize gif and png you need another header, so implement a switch case i.e. to get the type and use the right functions for these types.

   best regards,

   Harald Doderer
   Director Emedian Ltd.
   www.emedian.net

3. Ramesh N Sharma Says:
   August 24th, 2006 at 11:42 am

   short and useful tutorial

4. Jawad Shuaib Says:
   August 28th, 2006 at 9:41 am

   Thank you so much for this tutorial. This is exactly what I was looking for :) Thank you!

5. intekhab alam Says:
   August 29th, 2006 at 4:58 pm

   it help me to solve my problem so thanyou very much.

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