php常用图片处理类
<?
class image {
// 当前图片
protected $img;
// 图像types 对应表
protected $types = array(
1 => 'gif',
2 => 'jpg',
3 => 'png',
6 => 'bmp'
);
// image
public function __construct($img=''){
!$img && $this->param($img);
}
// Info
public function param($img){
$this->img = $img;
return $this;
}
// imageInfo
public function getImageInfo($img){
$info = @getimagesize($img);
if(isset($this->types[$info[2]])){
$info['ext'] = $info['type'] = $this->types[$info[2]];
} else{
$info['ext'] = $info['type'] = 'jpg';
}
$info['type'] == 'jpg' && $info['type'] = 'jpeg';
$info['size'] = @filesize($img);
return $info;
}
// thumb(新图地址, 宽, 高, 裁剪, 允许放大)
public function thumb($filename,$new_w=160,$new_h=120,$cut=0,$big=0){
// 获取原图信息
$info = $this->getImageInfo($this->img);
if(!emptyempty($info[0])) {
$old_w = $info[0];
$old_h = $info[1];
$type = $info['type'];
$ext = $info['ext'];
unset($info);
// 如果原图比缩略图小 并且不允许放大
if($old_w < $new_h && $old_h < $new_w && !$big){
return false;
}
// 裁剪图片
if($cut == 0){ // 等比列
$scale = min($new_w/$old_w, $new_h/$old_h); // 计算缩放比例
$width = (int)($old_w*$scale); // 缩略图尺寸
$height = (int)($old_h*$scale);
$start_w = $start_h = 0;
$end_w = $old_w;
$end_h = $old_h;
} elseif($cut == 1){ // center center 裁剪
$scale1 = round($new_w/$new_h,2);
$scale2 = round($old_w/$old_h,2);
if($scale1 > $scale2){
$end_h = round($old_w/$scale1,2);
$start_h = ($old_h-$end_h)/2;
$start_w = 0;
$end_w = $old_w;
} else{
$end_w = round($old_h*$scale1,2);
$start_w = ($old_w-$end_w)/2;
$start_h = 0;
$end_h = $old_h;
}
$width = $new_w;
$height= $new_h;
} elseif($cut == 2){ // left top 裁剪
$scale1 = round($new_w/$new_h,2);
$scale2 = round($old_w/$old_h,2);
if($scale1 > $scale2){
$end_h = round($old_w/$scale1,2);
$end_w = $old_w;
} else{
$end_w = round($old_h*$scale1,2);
$end_h = $old_h;
}
$start_w = 0;
$start_h = 0;
$width = $new_w;
$height= $new_h;
}
// 载入原图
$createFun = 'ImageCreateFrom'.$type;
$oldimg = $createFun($this->img);
// 创建缩略图
if($type!='gif' && function_exists('imagecreatetruecolor')){
$newimg = imagecreatetruecolor($width, $height);
} else{
$newimg = imagecreate($width, $height);
}
// 复制图片
if(function_exists("ImageCopyResampled")){
ImageCopyResampled($newimg, $oldimg, 0, 0, $start_w, $start_h, $width, $height, $end_w,$end_h);
} else{
ImageCopyResized($newimg, $oldimg, 0, 0, $start_w, $start_h, $width, $height, $end_w,$end_h);
}
// 对jpeg图形设置隔行扫描
$type == 'jpeg' && imageinterlace($newimg,1);
// 生成图片
$imageFun = 'image'.$type;
!@$imageFun($newimg,$filename) && die('保存失败!检查目录是否存在并且可写?');
ImageDestroy($newimg);
ImageDestroy($oldimg);
return $filename;
}
return false;
}
// water(保存地址,水印图片,水印位置,透明度)
public function water($filename,$water,$pos=0,$pct=80){
// 加载水印图片
$info = $this->getImageInfo($water);
if(!emptyempty($info[0])){
$water_w = $info[0];
$water_h = $info[1];
$type = $info['type'];
$fun = 'imagecreatefrom'.$type;
$waterimg = $fun($water);
} else{
return false;
}
// 加载背景图片
$info = $this->getImageInfo($this->img);
if(!emptyempty($info[0])){
$old_w = $info[0];
$old_h = $info[1];
$type = $info['type'];
$fun = 'imagecreatefrom'.$type;
$oldimg = $fun($this->img);
} else{
return false;
}
// 剪切水印
$water_w >$old_w && $water_w = $old_w;
$water_h >$old_h && $water_h = $old_h;
// 水印位置
switch($pos){
case 0://随机
$posX = rand(0,($old_w - $water_w));
$posY = rand(0,($old_h - $water_h));
break;
case 1://1为顶端居左
$posX = 0;
$posY = 0;
break;
case 2://2为顶端居中
$posX = ($old_w - $water_w) / 2;
$posY = 0;
break;
case 3://3为顶端居右
$posX = $old_w - $water_w;
$posY = 0;
break;
case 4://4为中部居左
$posX = 0;
$posY = ($old_h - $water_h) / 2;
break;
case 5://5为中部居中
$posX = ($old_w - $water_w) / 2;
$posY = ($old_h - $water_h) / 2;
break;
case 6://6为中部居右
$posX = $old_w - $water_w;
$posY = ($old_h - $water_h) / 2;
break;
case 7://7为底端居左
$posX = 0;
$posY = $old_h - $water_h;
break;
case 8://8为底端居中
$posX = ($old_w - $water_w) / 2;
$posY = $old_h - $water_h;
break;
case 9://9为底端居右
$posX = $old_w - $water_w;
$posY = $old_h - $water_h;
break;
default: //随机
$posX = rand(0,($old_w - $water_w));
$posY = rand(0,($old_h - $water_h));
break;
}
// 设定图像的混色模式
imagealphablending($oldimg, true);
// 添加水印
imagecopymerge($oldimg, $waterimg, $posX, $posY, 0, 0, $water_w,$water_h,$pct);
$fun = 'image'.$type;
!@$fun($oldimg, $filename) && die('保存失败!检查目录是否存在并且可写?');
imagedestroy($oldimg);
imagedestroy($waterimg);
return $filename;
}
}
?>
函数描述及例子
<?
//img类使用示例：
// 原始图片
//$img1 = './image/test.jpg';
// 水印后的图片
//$img2 = './image/test_new.jpg';
// 水印
//$water = './image/water.gif';
//$img = new image();
// 等比缩放
//$img->param($img1)->thumb('./image/test_0.jpg', 200,200,0);
// center center 裁剪
//$img->param($img1)->thumb('./image/test_1.jpg', 200,200,1);
// top left 裁剪
//$img->param($img1)->thumb('./image/test_2.jpg', 200,200,2);
// 右下角添加水印
//$img->param($img1)->water($img2,$water,9);
?>
