如何在 Codeigniter 中创建图像水印 wm_type 叠加层？答案

【问题标题】：How to create an image watermark wm_type overlay in Codeigniter?如何在 Codeigniter 中创建图像水印 wm_type 叠加层？
【发布时间】：2014-07-18 18:45:42
【问题描述】：

我正在尝试将图像放在另一个图像（水印）上，如下所示：

class Water_mark extends CI_Controller {

    function __construct() {
        parent::__construct();
    }

    function index() {
        $this->load->library('image_lib');
        $config['image_library'] = 'GD2';
        $config['source_image'] = '/assets/images/tv-share.jpg';
        $config['new_image'] = '/assets/images/tv-share-done.jpg';
        $config['wm_type'] = 'overlay';
        $config['wm_overlay_path'] = '/assets/images/share_en.jpg';
        $config['wm_opacity'] = '50';
        $config['wm_vrt_alignment'] = 'top'; 
        $config['wm_hor_alignment'] = 'left';
        $config['wm_hor_offset'] = '10';
        $config['wm_vrt_offset'] = '10';

        $data = $config;
        $this->image_lib->initialize($config);

        if (!$this->image_lib->watermark()) {
            echo $this->image_lib->display_errors();
        }
        $this->image_lib->clear();

        $this->load->view('water_mark_view', $data);
    }

}

但我不断收到错误：

A PHP Error was encountered
Severity: Warning
Message: imagecolorat() expects parameter 1 to be resource, boolean given
Filename: libraries/Image_lib.php
Line Number: 941
A PHP Error was encountered
Severity: Warning
Message: imagecolorat() expects parameter 1 to be resource, boolean given
Filename: libraries/Image_lib.php
Line Number: 953
A PHP Error was encountered
Severity: Warning
Message: imagecolortransparent() expects parameter 1 to be resource, boolean given
Filename: libraries/Image_lib.php
Line Number: 953
A PHP Error was encountered
Severity: Warning
Message: imagecopymerge() expects parameter 1 to be resource, boolean given
Filename: libraries/Image_lib.php
Line Number: 954
The path to the image is not correct.
The path to the image is not correct.
The path to the image is not correct.
Your server does not support the GD function required to process this type of image.
Your server does not support the GD function required to process this type of image.
Your server does not support the GD function required to process this type of image.

我错过了什么？

【问题讨论】：

标签： php codeigniter image-processing watermark

【解决方案1】：

问题很简单，就像在开头这样删除 正斜杠（尽管在 documentation example 中存在正斜杠）：

$config['source_image'] = 'assets/images/tv-share.jpg';
$config['new_image'] = 'assets/images/tv-share-done.jpg';
$config['wm_overlay_path'] = 'assets/images/share_en.jpg';

是什么让我对这个错误感到困惑：

您的服务器不支持处理此问题所需的 GD 函数图片类型。

看到上面的错误，没想到只是路径问题。

【讨论】：