PhP图片加水印

php图片加水印
同级目录加test目录

<?php
	wather('1.jpg');
	function wather($source, $water = '3.png' ,$position = 8, $alpha =100, $type='jpeg', $path ='test' , $isRandName =true)
	{
		//打开图片
		$sourceRes = open($source);
		
		$waterRes = open($water);
		
		//获取图片大小算出来位置
		$sourceInfo = getimagesize($source);
		$wateInfo = getimagesize($water);
		//算位置
		switch($position){
			case 1:
				$x = 0;
				$y = 0;
			break;
			case 2:
				$x = ($sourceInfo[0] -$wateInfo[0]);
				$y = 0;
			break;
			case 3:
				$x = ($sourceInfo[0] -$wateInfo[0]);
				$y = 0;
			break;
			case 4:
				$x = 0;
				$y = ($sourceInfo[1] -$wateInfo[1])/2;
			break;
			case 5:
				$x = ($sourceInfo[0] -$wateInfo[0])/2;
				$y = ($sourceInfo[1] -$wateInfo[1])/2;
			break;
			case 6:
				$x = ($sourceInfo[0] -$wateInfo[0]);
				$y = ($sourceInfo[1] -$wateInfo[1])/2;
			break;
			case 7:
				$x = 0;
				$y = ($sourceInfo[1] -$wateInfo[1]);
			break;
			case 8:
				$x = ($sourceInfo[0] -$wateInfo[0])/2;
				$y = ($sourceInfo[1] -$wateInfo[1]);
			break;
			case 9:
				$x = ($sourceInfo[0] -$wateInfo[0]);
				$y = ($sourceInfo[1] -$wateInfo[1]);
			break;
			default:
				$x=mt_rand(0, $sourceInfo[0]-$wateInfo[0]);
				$y=mt_rand(0, $sourceInfo[1]-$wateInfo[1]);
		}
		//把xy求出来的值
		imagecopymerge($sourceRes, $waterRes,$x,$y, 0, 0,$wateInfo[0],$wateInfo[1],$alpha);
		$func='image'.$type;
		//处理path路径是否启用随机文件名
		if($isRandName){
			$name = uniqid().'.'.$type;
			
		}else{
			$pathInfo = pathinfo($source);
			$name = $pathInfo['filename'].'.'.$type;
		}
		$path = rtrim($path.'/').'/'.$name;
		$func($sourceRes,$path);
		imagedestroy($sourceRes);
		imagedestroy($waterRes);
	}
	//打开图片函数
	
	function open($path)
	{
		//判断是否存在
		if(!file_exists($path)){
			exit('文件不存在');
		}
		$info = getimagesize($path);
		//var_dump($info);
		switch($info['mime']){
				case 'image/jpeg':
				case 'image/jpg':
				case 'image/pjpeg':
				$res = imagecreatefromjpeg($path); 
				break;
				case 'image/png':
				$res = imagecreatefrompng($path);
				break;
				case 'image/wbmp':
				case 'image/bmp':
				$res = imagecreatefromwbmp($path);
				break;
		}
		return $res;
	}