基于GD2图形库的PHP生成图片缩略图类代码分享

要使用PHP生成图片缩略图,要保证你的PHP服务器安装了GD2图形库使用一个类生成图片的缩略

要使用PHP生成图片缩略图,要保证你的PHP服务器安装了GD2图形库 使用一个类生成图片的缩略图

1.使用方法

$resizeimage = new resizeimage("图片源文件地址", "200", "100", "0","缩略图地址");
//就只用上面的一句话,就能生成缩略图,其中,源文件和缩略图地址可以相同,200,100分别代表宽和高

2. 缩略图类代码

//使用如下类就可以生成图片缩略图,
 
<?php
class resizeimage
{
 //图片类型
 var $type;
 //实际宽度
 var $width;
 //实际高度
 var $height;
 //改变后的宽度
 var $resize_width;
 //改变后的高度
 var $resize_height;
 //是否裁图
 var $cut;
 //源图象
 var $srcimg;
 //目标图象地址
 var $dstimg;
 //临时创建的图象
 var $im;
 
 function resizeimage($img, $wid, $hei,$c,$dstpath)
 {
 $this->srcimg = $img;
 $this->resize_width = $wid;
 $this->resize_height = $hei;
 $this->cut = $c;
 //图片的类型
 
$this->type = strtolower(substr(strrchr($this->srcimg,"."),1));
 
 //初始化图象
 $this->initi_img();
 //目标图象地址
 $this -> dst_img($dstpath);
 //--
 $this->width = imagesx($this->im);
 $this->height = imagesy($this->im);
 //生成图象
 $this->newimg();
 ImageDestroy ($this->im);
 }
 function newimg()
 {
 //改变后的图象的比例
 $resize_ratio = ($this->resize_width)/($this->resize_height);
 //实际图象的比例
 $ratio = ($this->width)/($this->height);
 if(($this->cut)=="1")
 //裁图
 {
 if($ratio>=$resize_ratio)
 //高度优先
 {
 $newimg = imagecreatetruecolor($this->resize_width,$this->resize_height);
 imagecopyresampled($newimg, $this->im, 0, 0, 0, 0, $this->resize_width,$this->resize_height, (($this->height)*$resize_ratio), $this->height);
 ImageJpeg ($newimg,$this->dstimg);
 }
 if($ratio<$resize_ratio)
 //宽度优先
 {
 $newimg = imagecreatetruecolor($this->resize_width,$this->resize_height);
 imagecopyresampled($newimg, $this->im, 0, 0, 0, 0, $this->resize_width, $this->resize_height, $this->width, (($this->width)/$resize_ratio));
 ImageJpeg ($newimg,$this->dstimg);
 }
 }
 else
 //不裁图
 {
 if($ratio>=$resize_ratio)
 {
 $newimg = imagecreatetruecolor($this->resize_width,($this->resize_width)/$ratio);
 imagecopyresampled($newimg, $this->im, 0, 0, 0, 0, $this->resize_width, ($this->resize_width)/$ratio, $this->width, $this->height);
 ImageJpeg ($newimg,$this->dstimg);
 }
 if($ratio<$resize_ratio)
 {
 $newimg = imagecreatetruecolor(($this->resize_height)*$ratio,$this->resize_height);
 imagecopyresampled($newimg, $this->im, 0, 0, 0, 0, ($this->resize_height)*$ratio, $this->resize_height, $this->width, $this->height);
 ImageJpeg ($newimg,$this->dstimg);
 }
 }
 }
 //初始化图象
 function initi_img()
 {
 if($this->type=="jpg")
 {
 $this->im = imagecreatefromjpeg($this->srcimg);
 }
 if($this->type=="gif")
 {
 $this->im = imagecreatefromgif($this->srcimg);
 }
 if($this->type=="png")
 {
 $this->im = imagecreatefrompng($this->srcimg);
 }
 }
 //图象目标地址
 function dst_img($dstpath)
 {
 $full_length = strlen($this->srcimg);
 
 $type_length = strlen($this->type);
 $name_length = $full_length-$type_length;
 
 
 $name = substr($this->srcimg,0,$name_length-1);
 $this->dstimg = $dstpath;
 
 
//echo $this->dstimg;
 }
}
?>

GD2 图形库 PHP生成图片缩略图类