PHP生成缩略图

上一篇 / 下一篇 2007-07-24 04:34:47

代码很丑陋，在别人的基础上弄的。
功能稍加完善
上传文件支持辨别大写+小写，不再是只认小写不认大写。
支持中文文件名，上传后写入不再为乱码。
网页为UTF-8
运行请打开php.ini里的GD库和MB库，第一个处理图像用，第二个处理内码用。
主目录下有
ratioimg.html
ratioimg.php
image文件夹，运行请新建此文件夹

ratioimg.html
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>上传图片</title>
</head>

<body>
<form id="ratioimg" name="ratioimg" enctype="multipart/form-data" method="post" action="ratioimg.php">
<label>
<input type="file" name="file" />
</label>
<p>
    <label>
    <input type="submit" name="Submit" value="提交" />
    </label>
</p>
</form>
</body>
</html>

ratioimg.php
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>缩略图生成</title>
</head>
<?
/***************************************/
/*功能：利用PHP的GD库生成高质量的缩略图*/
/*运行环境:PHP5.01/GD2*/
/*类说明：可以选择是/否裁图。

                  如果裁图则生成的图的尺寸与您输入的一样。
                  原则：尽可能多保持原图完整

                  如果不裁图，则按照原图比例生成新图
                  原则：根据比例以输入的长或者宽为基准*/
/*参数：$img:源图片地址
                 $wid:新图的宽度
                 $hei:新图的高度
                 $c:是否裁图，1为是，0为否*/
/* Author: antplus         */
/* version: 1.1             */
/* QQ:      38188141        */
/* MSN:     [email]antplus@163.net[/email] */
/***************************************/
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)
        {
                //echo $img.$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();
                //imagesx imagesy 取得图像宽、高
                $this->width = imagesx($this->im);
                $this->height = imagesy($this->im);
                //生成图象
                $this->newimg();
                ImageDestroy ($this->im);
        }
        function newimg()
        {

                // +----------------------------------------------------+
                // | 增加LOGO到缩略图中 Modify By Ice
                // +----------------------------------------------------+
                //Add Logo
                //$logoImage = ImageCreateFromJPEG('t_a.jpg');
                //ImageAlphaBlending($this->im, true);
                //$logoW = ImageSX($logoImage);
                //$logoH = ImageSY($logoImage);
                // +----------------------------------------------------+

                //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
                        {
                                //imagecreatetruecolor — 新建一个真彩色图像
                                $newimg = imagecreatetruecolor($this->resize_width,$this->resize_height);
                                //imagecopyresampled — 重采样拷贝部分图像并调整大小
                                imagecopyresampled($newimg, $this->im, 0, 0, 0, 0, $this->resize_width,$this->resize_height, (($this->height)*$resize_ratio), $this->height);

                                // +----------------------------------------------------+
                                // | 增加LOGO到缩略图中 Modify By Ice
                                // +----------------------------------------------------+
                                //ImageCopy($newimg, $logoImage, 0, 0, 0, 0, $logoW, $logoH);
                                // +----------------------------------------------------+

                                //imagejpeg — 以 JPEG 格式将图像输出到浏览器或文件
                                ImageJpeg ($newimg,$this->dstimg);
                                echo "缩略图生成成功！";
                        }
                        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));

                                // +----------------------------------------------------+
                                // | 增加LOGO到缩略图中 Modify By Ice
                                // +----------------------------------------------------+
                                //ImageCopy($newimg, $logoImage, 0, 0, 0, 0, $logoW, $logoH);
                                // +----------------------------------------------------+

                                ImageJpeg ($newimg,$this->dstimg);
                                echo "缩略图生成成功！";
                        }

                }
                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);

                                // +----------------------------------------------------+
                                // | 增加LOGO到缩略图中 Modify By Ice
                                // +----------------------------------------------------+
                                //ImageCopy($newimg, $logoImage, 0, 0, 0, 0, $logoW, $logoH);
                                // +----------------------------------------------------+

                                ImageJpeg ($newimg,$this->dstimg);
                                echo "缩略图生成成功！";
                        }
                        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);

                                // +----------------------------------------------------+
                                // | 增加LOGO到缩略图中 Modify By Ice
                                // +----------------------------------------------------+
                                //ImageCopy($newimg, $logoImage, 0, 0, 0, 0, $logoW, $logoH);
                                // +----------------------------------------------------+

                                ImageJpeg ($newimg,$this->dstimg);
                                echo "缩略图生成成功！";
                        }
                }

                // +----------------------------------------------------+
                // | 释放资源 Modify By Ice
                // +----------------------------------------------------+
                //ImageDestroy($logoImage);
                // +----------------------------------------------------+

        }
        //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);
                }
        }
        /*
        function initi_img($f)
        {
            //GetImageSize获取图像信息，数组表示，print_r ($data);
            $data=GetImageSize($f);
            switch($data[2]){
            case 1:
                $this->im = imagecreatefromgif($f);
                break;
            case 2:
                $this->im = imagecreatefromjpeg($f);
                break;
            case 3:
                $this->im = imagecreatefrompng($f);
                break;
            }
        }
        */
        //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;
        }
}

/*
print_r($_FILES["file"]);
foreach ($_FILES["file"] as $key => $a)
{
    echo $key."=============".$a."<br>";
}
*/
$tempimgname = strtolower($_FILES["file"][name]);
//mb_convert_encoding转换传输字集encod
$tempimgname = mb_convert_encoding(   $tempimgname,   "gb2312",   "utf-8");
//echo $tempimgname;
$tmpfiletype = substr(strrchr($tempimgname,"."),1);

/*
echo $tmpfiletype."----------------"."<br>";
//explode 以某个字符串分割。
$firsttmpfilename = explode(".",$_FILES["file"][tmp_name]);
echo $firsttmpfilename[0]."<br>";
$tempimgname = $firsttmpfilename[0].".".$tmpfiletype;
echo $tempimgname."<br>";
*/
if($tmpfiletype=="jpg" || $tmpfiletype=="gif" || $tmpfiletype=="png")
{
        if(copy($_FILES["file"]["tmp_name"],strtolower("image\\".date("Y-m-",time()).$tempimgname)))
        {
            //输出原来的文件名，大小，类型
            echo "文件".strtolower($_FILES["file"]["name"])."<br>"."大小".$_FILES["file"]["size"]."<br>"."文件类型为".$_FILES["file"]["type"]."<br>"."文件上传成功!"."<br>";
        }
        else
        {
            echo "文件上传失败"."<br>";
        }
    $class = new resizeimage("image\\".date("Y-m-",time()).$tempimgname, 120, 160, 1);
}
else
{
    echo "上传文件类型错误，请勿上传除jpg,gif,png以外的其他文件。";
}

?>

$class = new resizeimage("image\\".date("Y-m-",time()).$tempimgname, 120, 160, 1);内120,160为想改变的图像大小。1为截图，0为不截图，具体效果请自行体会。