PHP resizer - Web Design Forum Graphic Design Site Templates Flash CSS Discussions

Sakari · #1 08-25-2008, 10:29 AM

Hi

Resizing an image in PHP and maintaining its aspect ratio
________________________________________
A question that has been asked many times is how to resize an image in PHP while maintaining the aspect ration of the original image.

The function below does just that, it takes an image resource and the new dimensions for the image in pixels and returns the resized image.

Quote:

Code:
/**
* Resize and image while maintaining its aspect ratio.
*
* @param resource $src The image to resize.
* @param int $w The target width.
* @param int $h The target height.
* @return resource The resized image or the original image if it did not need to be scaled.
*/
function resizeImage($src, $w, $h) {

// Get the current size
$width = ImageSx($src);
$height = ImageSy($src);

// If one dimension is right then nothing to do
if($width == $w || $height == $h)
return($src);

// Calculate new size
if(($w - $width) > ($h - $height)) { // use height
$s = $h / $height;
$nw = round($width * $s);
$nh = round($height * $s);
}
else { // Use width
$s = $w / $width;
$nw = round($width * $s);
$nh = round($height * $s);
}

// Resize to correct size
$im = ImageCreateTrueColor($nw, $nh);
ImageCopyResampled($im, $src, 0, 0, 0, 0, $nw, $nh, $width, $height);

// Return the new image
return($im);
}
A simple example to load, resize and send an image to the browser would be:
Code:
$image = ImageCreateFromJPEG('images.jpg');
$image = resizeImage($image, 400, 400);
header("Content-Type: image/jpeg");
ImageJPEG($image, '', 80);

thanks

orlando · #2 11-15-2008, 09:36 AM

hi sakari

its not properly work but some changes make it perfect.

thanks

vks87 · #3 03-06-2009, 05:00 AM

ya absolutely orlando is right.I am fully agreed with orlando you should do that which he said you..

peterjack15 · #4 08-11-2011, 06:00 AM

ya absolutely orlando is right.I am fully agreed with orlando you should do that which he said you..

amankumar · #5 08-26-2011, 08:40 AM

<?php

/*
* File: SimpleImage.php
* Author: Simon Jarvis
* Copyright: 2006 Simon Jarvis
* Date: 08/11/06
* Link: http://www.white-hat-web-design.co.u...e-resizing.php
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details:
* http://www.gnu.org/licenses/gpl.html
*
*/

aman1 · #6 08-26-2011, 10:18 AM

Thanks for sharing the useful information.