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.
