使用codeigniter图像库-转换图像

使用codeigniter图像库是否可以只更改图像类型？正在尝试从*->PNG转换

下面的代码不起作用

$config = array();
$config['source_image']='uploads/'.$name.'.'.$m[1];
$config['new_image']='uploads/'.$name.'.'.$png;
$objImage = new CI_Image_lib($config);

非常感谢！非常感谢大家的帮助

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目前正在使用，但希望使用图像库并支持所有图像类型

$sourceImage = imagecreatefromjpeg('uploads/'.$name.'.'.$m[1]);
imagepng($sourceImage, 'uploads/'.$name.'.png');

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我认为您必须使用

ImageMagick

$config['image_library'] = 'ImageMagick';
$config['library_path']='/usr/bin';
$config['source_image']='uploads/'.$name.'.'.$m[1];
$config['new_image']='uploads/'.$name.'.'.$png;
$objImage = new CI_Image_lib($config);

---

在阅读了许多不同的解决方案之后，我决定放弃CodeIgniter的库，而是使用一个非常简单的类 （最初发布在上，但同时被删除）

将其粘贴到此处供子孙后代使用：

<?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;
    }
}
?>

有关基于CI的扩展，请参见此处：