基于GD2图形库的PHP生成图片缩略图类代码分享

基于GD2图形库的PHP生成图片缩略图类代码分享

 这篇文章主要介绍了基于GD2图形库的PHP生成图片缩略图类代码分享,本文直接给出实现代码和使用方法,需要的朋友可以参考下

 

 

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

?

1 2	$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

?

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119

//使用如下类就可以生成图片缩略图,   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 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 //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; } }