PHP生成等比缩略图类和自定义函数分享

这篇文章主要介绍了PHP生成等比缩略图类和自定义函数分享,分别封装成了一个类和自定义函数,需要的朋友可以参考下

共有两种等比例缩略图方法可以借鉴
一、为类文件，实例化之后即可使用
二、为自定义方法，，比较轻巧

类文件

复制代码 代码如下:

$resizeimage = new resizeimage("./shawn.jpg", "200", "100", "0","../pic/shawnsun.jpg");
//实例化下面的类,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，第四个参数为可选 0不截图，1为截图

复制代码 代码如下:

class resizeimage{

//图片类型
public $type;
//实际宽度
public $width;
//实际高度
public $height;
//改变后的宽度
public $resize_width;
//改变后的高度
public $resize_height;
//是否裁图
public $cut;
//源图象
public $srcimg;
//目标图象地址
public $dstimg;
//临时创建的图象
public $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);
//W & H
$this->width = imagesx($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 //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 {
$newimg = imagecreatetruecolor(($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;
}
}

?>

自定义方法

复制代码 代码如下:

thumbs('shawn.jpg','shawnsun.jpg',100,100);
//参数属性类似于方法一

复制代码 代码如下: