php生成水印函数

/* * 图片加水印 * $source string 图片资源 * $target string 添加水印后的名字 * $w_pos int 水印位置 具体看代码 * $w_img string 水印图片路径 * $w_text string 显示的文字 * $w_font int 字体大小 * $w_color string 字体颜色 */ function watermark($source, $target = '', $w_pos = '', $w_img = '', $w_text = '80shihua.com', $w_font = 10, $w_color = '#CC0000') { if (!$target) { $target = $source; } $w_minwidth = 200; $w_minheight = 200; $w_quality =90;//图像质量 $w_pct = 85; //透明度 $source_info = getimagesize($source); //图片信息 $source_w = $source_info[0]; //图片宽度 $source_h = $source_info[1]; //图片高度 if ($source_w < $w_minwidth || $source_h < $w_minheight) { return false; } switch ($source_info[2]) { //图片类型 case 1: //GIF格式 $source_img = imagecreatefromgif($source); break; case 2: //JPG格式 $source_img = imagecreatefromjpeg($source); break; case 3: //PNG格式 $source_img = imagecreatefrompng($source); //imagealphablending($source_img,false); //关闭混色模式 imagesavealpha($source_img, true); //设置标记以在保存 PNG 图像时保存完整的 alpha 通道信息(与单一透明色相反) break; default: return false; } if (!empty($w_img) && file_exists($w_img)) { //水印图片有效 $ifwaterimage = 1; //标记 $water_info = getimagesize($w_img); $width = $water_info[0]; $height = $water_info[1]; switch ($water_info[2]) { case 1: $water_img = imagecreatefromgif($w_img); break; case 2: $water_img = imagecreatefromjpeg($w_img); break; case 3: $water_img = imagecreatefrompng($w_img); //imagealphablending($w_img, false); //imagesavealpha($w_img, true); break; default: return; } } else { $path = '/80shihua.ttf'; $ifwaterimage = 0; $temp = imagettfbbox(ceil($w_font * 2.5), 0, $path, $w_text); //imagettfbbox返回一个含有 8 个单元的数组表示了文本外框的四个角 $width = $temp[2] - $temp[6]; $height = $temp[3] - $temp[7]; unset($temp); } switch ($w_pos) { case 1: $wx = 5; $wy = 5; break; case 2: $wx = ($source_w - $width) / 2; $wy = 0; break; case 3: $wx = $source_w - $width; $wy = 0; break; case 4: $wx = 0; $wy = ($source_h - $height) / 2; break; case 5: $wx = ($source_w - $width) / 2; $wy = ($source_h - $height) / 2; break; case 6: $wx = $source_w - $width; $wy = ($source_h - $height) / 2; break; case 7: $wx = 0; $wy = $source_h - $height; break; case 8: $wx = ($source_w - $width) / 2; $wy = $source_h - $height; break; case 9: $wx = $source_w - ($width + 5); $wy = $source_h - ($height + 5); break; case 10: $wx = rand(0, ($source_w - $width)); $wy = rand(0, ($source_h - $height)); break; default: $wx = rand(0, ($source_w - $width)); $wy = rand(0, ($source_h - $height)); break; } if ($ifwaterimage) { if ($water_info[2] == 3) { imagecopy($source_img, $water_img, $wx, $wy, 0, 0, $width, $height); } else { imagecopymerge($source_img, $water_img, $wx, $wy, 0, 0, $width, $height, $this->w_pct); } } else { if (!empty($w_color) && (strlen($w_color) == 7)) { $r = hexdec(substr($w_color, 1, 2)); $g = hexdec(substr($w_color, 3, 2)); $b = hexdec(substr($w_color, 5)); } else { return; } imagestring($source_img, $w_font, $wx, $wy, $w_text, imagecolorallocate($source_img, $r, $g, $b)); } switch ($source_info[2]) { case 1: imagegif($source_img, $target); //GIF 格式将图像输出到浏览器或文件(欲输出的图像资源, 指定输出图像的文件名) break; case 2: imagejpeg($source_img, $target, $this->w_quality); break; case 3: imagepng($source_img, $target); break; default: return; } if (isset($water_info)) { unset($water_info); } if (isset($water_img)) { imagedestroy($water_img); } unset($source_info); imagedestroy($source_img); return true; } 存在水印图片则根据图片生成水印,否则调用80shihua.ttf字体文件生成水印,水印文字可以自己指定.