Прочитав много разных решений, я решил отказаться от библиотеки CodeIgniter и вместо этого использовать очень простой класс, заданный здесь (изначально был размещен на http://www.white -hat-web-design.co.uk/blog/resizing-images-with-php/, но в то же время был удален).
Вставить его сюда для потомков:
<?php
/* * File: SimpleImage.php * Author: Simon Jarvis * Copyright: 2006 Simon Jarvis * Date: 08/11/06 * Link: http://www.white-hat-web-design.co.uk/articles/php-image-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 * */
class SimpleImage
{
var $image;
var $image_type;
function load($filename)
{
$image_info = getimagesize($filename);
$this->image_type = $image_info[2];
if ($this->image_type == IMAGETYPE_JPEG) {
$this->image = imagecreatefromjpeg($filename);
} elseif ($this->image_type == IMAGETYPE_GIF) {
$this->image = imagecreatefromgif($filename);
} elseif ($this->image_type == IMAGETYPE_PNG) {
$this->image = imagecreatefrompng($filename);
}
}
function save($filename, $image_type = IMAGETYPE_JPEG, $compression = 75, $permissions = null)
{
if ($image_type == IMAGETYPE_JPEG) {
imagejpeg($this->image, $filename, $compression);
} elseif ($image_type == IMAGETYPE_GIF) {
imagegif($this->image, $filename);
} elseif ($image_type == IMAGETYPE_PNG) {
imagepng($this->image, $filename);
}
if ($permissions != null) {
chmod($filename, $permissions);
}
}
function output($image_type = IMAGETYPE_JPEG)
{
if ($image_type == IMAGETYPE_JPEG) {
imagejpeg($this->image);
} elseif ($image_type == IMAGETYPE_GIF) {
imagegif($this->image);
} elseif ($image_type == IMAGETYPE_PNG) {
imagepng($this->image);
}
}
function getWidth()
{
return imagesx($this->image);
}
function getHeight()
{
return imagesy($this->image);
}
function resizeToHeight($height)
{
$ratio = $height / $this->getHeight();
$width = $this->getWidth() * $ratio;
$this->resize($width, $height);
}
function resizeToWidth($width)
{
$ratio = $width / $this->getWidth();
$height = $this->getheight() * $ratio;
$this->resize($width, $height);
}
function scale($scale)
{
$width = $this->getWidth() * $scale / 100;
$height = $this->getheight() * $scale / 100;
$this->resize($width, $height);
}
function resize($width, $height)
{
$new_image = imagecreatetruecolor($width, $height);
imagecopyresampled($new_image, $this->image, 0, 0, 0, 0, $width, $height, $this->getWidth(), $this->getHeight());
$this->image = $new_image;
}
}
?>
Для КИ на основерасширение смотрите здесь: http://www.robertmullaney.com/2010/09/18/codeigniter-image_lib-convert-jpg-gif-png/