一个正规的网站，在需要上传图片时，往往都会需要在图片上增加自己网站的LOGO水印。那么如何实现这一步骤呢？首先让我们来了解
通过判断文件类型建立图形，然后把其复制到原建立的图形上，填充并建立rectangle，以备写入imagestring()或是在原已经定好的图像程序当中判断水印类型：一是字符串，另是增加一个图形对象在上面。以下是PHP图片加水印的转载！
参数说明:
$max_file_size : 上传文件大小限制, 单位BYTE
$destination_folder : 上传文件路径
$watermark : 是否附加水印(1为加水印,其他为不加水印);
PHP图片加水印使用说明:
1. 将PHP.INI文件里面的"extension=php_gd2.dll"一行前面的;号去掉,因为我们要用到GD库;
2. 将extension_dir =改为你的php_gd2.dll所在目录;
PHP图片加水印的代码示例：
<ol class="dp-xml"> <li class="alt"><span><span>//上传文件类型列表 </span></span></li> <li> <span>$</span><span class="attribute">uptypes</span><span>=</span><span class="attribute-value">array</span><span>( </span> </li> <li class="alt"><span>'image/jpg', </span></li> <li><span>'image/jpeg', </span></li> <li class="alt"><span>'image/png', </span></li> <li><span>'image/pjpeg', </span></li> <li class="alt"><span>'image/gif', </span></li> <li><span>'image/bmp', </span></li> <li class="alt"><span>'image/x-png' </span></li> <li><span>); </span></li> <li class="alt"> <span>$</span><span class="attribute">max_file_size</span><span>=</span><span class="attribute-value">2000000</span><span>; //上传文件大小限制, 单位BYTE </span> </li> <li> <span>$</span><span class="attribute">destination_folder</span><span>=</span><span class="attribute-value">"uploadimg/"</span><span>; //上传文件路径 </span> </li> <li class="alt"> <span>$</span><span class="attribute">watermark</span><span>=</span><span class="attribute-value">1</span><span>; //是否附加水印(1为加水印,其他为不加水印); </span> </li> <li> <span>$</span><span class="attribute">watertype</span><span>=</span><span class="attribute-value">1</span><span>; //水印类型(1为文字,2为图片) </span> </li> <li class="alt"> <span>$</span><span class="attribute">waterposition</span><span>=</span><span class="attribute-value">1</span><span>; //水印位置(1为左下角,2为右下角 </span> </li> <li><span>,3为左上角,4为右上角,5为居中); </span></li> <li class="alt"> <span>$</span><span class="attribute">waterstring</span><span>="</span><span class="tag"><span> </span><span class="tag-name">A</span><span> href="</span><span class="attribute-value">http</span><span>://www.xplore.cn/"</span><span class="tag">></span><span> </span></span> </li> <li> <span>http://www.xplore.cn/</span><span class="tag"><span> /A</span><span class="tag">></span><span>"; //水印字符串 </span></span> </li> <li class="alt"> <span>$</span><span class="attribute">waterimg</span><span>=</span><span class="attribute-value">"xplore.gif"</span><span>; //水印图片 </span> </li> <li> <span>$</span><span class="attribute">imgpreview</span><span>=</span><span class="attribute-value">1</span><span>; //是否生成预览图(1为生成,其他为不生成); </span> </li> <li class="alt"> <span>$</span><span class="attribute">imgpreviewsize</span><span>=</span><span class="attribute-value">1</span><span>/2; //缩略图比例 </span> </li> <li> <span class="tag">?></span><span> </span> </li> <li class="alt"><span class="tag"><span> </span><span class="tag-name">html</span><span class="tag">></span><span> </span></span></li> <li><span class="tag"><span> </span><span class="tag-name">head</span><span class="tag">></span><span> </span></span></li> <li class="alt"><span class="tag"><span> </span><span class="tag-name">title</span><span class="tag">></span><span>ZwelL图片上传程序</span><span class="tag"></span><span class="tag-name">title</span><span class="tag">></span><span> </span></span></li> <li><span class="tag"><span> </span><span class="tag-name">style</span><span> </span><span class="attribute">type</span><span>=</span><span class="attribute-value">"text/css"</span><span class="tag">></span><span> </span></span></li> <li class="alt"><span></span></li> </ol>
