PHP图片水印缩放类实现

tiyan

　　


<?php
class Image{
private $path;

function __construct($path='./'){
$this->path=rtrim($path,'/').'/';
}
//水印函数，参数：背景图，水印图，位置，前缀,TMD透明度
public function water($b,$l,$pos=9,$prefix='wa_',$tmd=100){
//拼接路径
$b=$this->path.$b;
$l=$this->path.$l;
//判断路径
if(file_exists($b)&&file_exists($l)){
//获取信息
$binfo=self::getImageInfo($b);
$linfo=self::getImageInfo($l);
//判断大小
if(!self::checkSize($binfo,$linfo)){
exit('背景图片大小小于水印图片大小');
}
//取得位置
$position=self::getPosition($binfo,$linfo,$pos);
//打开资源
$bRes=self::openImg($b,$binfo['type']);
$lRes=self::openImg($l,$linfo['type']);
//合成
$newRes=self::mergeImg($bRes,$lRes,$linfo,$position,$tmd);
//保存
if($name=self::saveImg($newRes,$this->path,$prefix,$binfo)){
return $name;
}
}else{
echo '路径不存在';
exit;
}
}

//thumb 等比缩放方法
public function thumb($img,$width,$height,$prefix='th_'){
$img=$this->path.$img;
if(!file_exists($img)){
exit('楼下有美女，提示你图片路径不存在');
}
$info=self::getImageInfo($img);
$newSize=self::getNewSize($width,$height,$info);
$res=self::openImg($img,$info['type']);
$newRes=self::kidOfImage($res,$newSize,$info);
if($name=self::saveImg($newRes,$this->path,$prefix,$info)){
return $name;
}

}
static private function saveImg($res,$path,$prefix,$binfo){
$name=$path.$prefix.$binfo['name'];
switch($binfo['type']){
case 'image/jpeg':
case 'image/jpg':
case 'image/pjpeg':
imagejpeg($res,$name);
break;
case 'image/png':
case 'image/x-png':
imagepng($res,$name);
break;
case 'image/gif':
imagegif($res,$name);
break;
case 'image/wbmp':
imagewbmp($res,$name);
break;
default:
echo '不支持这个图片类型解析';
break;
}
return $name;
}
static private function mergeImg($b,$l,$linfo,$p,$tmd){
imagecopymerge($b,$l,$p['x'],$p['y'],0,0,$linfo['width'],$linfo['height'],$tmd);
return $b;
}
static private function openImg($path,$type){
switch($type){
case 'image/jpeg':
case 'image/jpg':
case 'image/pjpeg':
$res=imagecreatefromjpeg($path);
break;
case 'image/gif':
$res=imagecreatefromgif($path);
break;
case 'image/wbmp':
$res=imagecreatefromwbmp($path);
break;
case 'image/png':
case 'image/x-png':
$res=imagecreatefrompng($path);
break;
default:
echo '图片类型不支持';
exit;
}
return $res;
}
static private function getPosition($b,$l,$pos){
switch($pos){
case 1:
$x=0;
$y=0;
break;
case 2:
$x=floor(($b['width']-$l['width'])/2);
$y=0;
break;
case 3:
$x=$b['width']-$l['width'];
$y=0;
break;
case 4:
$x=0;
$y=ceil(($b['height']-$l['height'])/2);
break;
case 5:
$x=floor(($b['width']-$l['width'])/2);
$y=ceil(($b['height']-$l['height'])/2);
break;
case 6:
$x=$b['width']-$l['width'];
$y=ceil(($b['height']-$l['height'])/2);
break;
case 7:
$x=0;
$y=$b['height']-$l['height'];
break;
case 8:
$x=floor(($b['width']-$l['width'])/2);
$y=$b['height']-$l['height'];
break;
case 9:
$x=$b['width']-$l['width'];
$y=$b['height']-$l['height'];
break;
default:
$x=mt_rand(0,$b['width']-$l['width']);
$y=mt_rand(0,$b['height']-$l['height']);
break;
}
return array('x'=>$x,'y'=>$y);
}
static private function checkSize($b,$l){
if($b['width']<$l['width']||$b['height']<$l['height']){
return false;
}else{
return true;
}
}
static private function getImageInfo($path){
$info=getimagesize($path);
$data['width']=$info[0];
$data['height']=$info[1];
$data['type']=$info['mime'];
$data['name']=basename($path);
return $data;
}
static private function kidOfImage($srcImg,$size, $imgInfo){
$newImg = imagecreatetruecolor($size["width"], $size["height"]);
$otsc = imagecolortransparent($srcImg);
if( $otsc >= 0 && $otsc < imagecolorstotal($srcImg)) {
$transparentcolor = imagecolorsforindex( $srcImg, $otsc );
$newtransparentcolor = imagecolorallocate(
$newImg,
$transparentcolor['red'],
$transparentcolor['green'],
$transparentcolor['blue']
);
imagefill( $newImg, 0, 0, $newtransparentcolor );
imagecolortransparent( $newImg, $newtransparentcolor );
}

imagecopyresized( $newImg, $srcImg, 0, 0, 0, 0, $size["width"], $size["height"], $imgInfo["width"], $imgInfo["height"] );
imagedestroy($srcImg);
return $newImg;
}
static private function getNewSize($width, $height,$imgInfo){
$size["width"]=$imgInfo["width"];          //将原图片的宽度给数组中的$size["width"]
$size["height"]=$imgInfo["height"];        //将原图片的高度给数组中的$size["height"]
if($width < $imgInfo["width"]){
$size["width"]=$width;             //缩放的宽度如果比原图小才重新设置宽度
}
if($width < $imgInfo["height"]){
$size["height"]=$height;            //缩放的高度如果比原图小才重新设置高度
}
if($imgInfo["width"]*$size["width"] > $imgInfo["height"] * $size["height"]){
$size["height"]=round($imgInfo["height"]*$size["width"]/$imgInfo["width"]);
}else{
$size["width"]=round($imgInfo["width"]*$size["height"]/$imgInfo["height"]);
}
return $size;
}

}
?>