php类-resizeimage类-图片生成缩略图

<?


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[separator]


var $dstimg;


//临????建的图象


var $im;








function resizeimage($img, $wid, $hei,$c)


{


$this->srcimg = $img;


$this->resize_width = $wid;


$this->resize_height = $hei;


$this->cut = $c;


//图片的类型


$this->type = substr(strrchr($this->srcimg,"."),1);


//初始化图象


$this->initi_img();


//目标图象地址


$this -> dst_img();


//--


$this->width = imagesx($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()


{


$full_length = strlen($this->srcimg);


$type_length = strlen($this->type);


$name_length = $full_length-$type_length;


$name = substr($this->srcimg,0,$name_length-1);


$this->dstimg = $name."_small.".$this->type;


}


}








$resizeimage = new resizeimage("test.jpg", "200", "200", "1");










?>