跳至
//获取真实的图片类型
list($width, $height, $type, $attr) = getimagesize($this->sur_file);
switch($type) {
case 1 :
$img_type = 'gif';
break;
case 2 :
$img_type = 'jpeg';
break;
case 3 :
$img_type = 'png';
break;
case 15 :
$img_type = 'wbmp';
break;
default :
return false;
}
//下面把修改后的生成缩略图的类贴出来，供大家指正~
/**
* php生成缩略图类
* 修改者 点点细雨
* 文章出处 ： http://blog.csdn.net/diandianxiyu_geek
* 2014-07-23 解决了图片类型不能正常识别的问题
*/
class thumb {
public $sur_file; //读取的原图片
public $des_file; //生成目标图片
public $tem_file; //临时图片
public $tag; //缩略标签 0,默认,按固定的高宽生成 1,按比列或固定最大长度生成 -1,按某个宽度或某个高度缩小
public $resize_width; //$tag为0时,目标文件宽
public $resize_height; //$tag为0时,目标文件高
public $sca_max; //$tag为1时,<0$sca_max1时为最大长度(高或宽之中的最大值)
public $type; //图片类型
public $width; //原图片宽
public $height; //原图片高
public $size; //原图大小
//构造函数
public function __construct($surpic, $reswid, $reshei, $despic, $mark, $scamax) {
$this->sur_file = $surpic;
$this->resize_width = $reswid;
$this->resize_height = $reshei;
$this->tag = $mark;
$this->sca_max = $scamax;
list($width, $height, $type, $attr) = getimagesize($this->sur_file);
switch ($type) {
case 1 :
$img_type = 'gif';
break;
case 2 :
$img_type = 'jpeg';
break;
case 3 :
$img_type = 'png';
break;
case 15 :
$img_type = 'wbmp';
break;
default :
return false;
}
$this->type = $img_type; //获取图片类型
$this->init_img(); //初始化图片
$this->des_file = $despic; //目标图片地址
$this->width = $width;
$this->height = $height;
$this->size = filesize($surpic);
$this->new_img();
imagedestroy($this->tem_file);
}
//图片初始化函数
private function init_img() {
if ($this->type == 'jpeg') {
$this->tem_file = imagecreatefromjpeg($this->sur_file);
} elseif ($this->type == 'jpg') {
$this->tem_file = imagecreatefromjpeg($this->sur_file);
} elseif ($this->type == 'gif') {
$this->tem_file = imagecreatefromgif($this->sur_file);
} elseif ($this->type == 'png') {
$this->tem_file = imagecreatefrompng($this->sur_file);
} elseif ($this->type == 'bmp') {
$this->tem_file = imagecreatefrombmp($this->sur_file); //bmp.php中包含
}
}
//图片生成函数
private function new_img() {
$ratio = ($this->width) / ($this->height); //原图比例
$resize_ratio = ($this->resize_width) / ($this->resize_height); //缩略后比例
$newimg = imagecreatetruecolor($this->resize_width, $this->resize_height); //生成新图片
imagealphablending($newimg, false); //这里很重要,意思是不合并颜色,直接用$img图像颜色替换,包括透明色;
imagesavealpha($newimg, true);
if ($this->tag == 0) { //按固定高宽截取缩略图
$newimg = imagecreatetruecolor($this->resize_width, $this->resize_height); //生成新图片
if ($ratio >= $resize_ratio) {//即等比例下,缩略图的高比原图长,因此高不变
imagecopyresampled($newimg, $this->tem_file, 0, 0, 0, 0, $this->resize_width, $this->resize_height, (($this->height) * $resize_ratio), $this->height);
} elseif ($ratio < $resize_ratio) {//即等比例下,缩略图的宽比原图长,因此宽不变
imagecopyresampled($newimg, $this->tem_file, 0, 0, 0, 0, $this->resize_width, $this->resize_height, $this->width, (($this->width) / $resize_ratio));
}
} elseif ($this->tag == 1) { //按固定比例或最大长度缩小
if ($this->sca_max < 1) { //按比例缩小
$newimg = imagecreatetruecolor((($this->width) * ($this->sca_max)), (($this->height) * ($this->sca_max))); //生成新图片
imagecopyresampled($newimg, $this->tem_file, 0, 0, 0, 0, (($this->width) * ($this->sca_max)), (($this->height) * ($this->sca_max)), $this->width, $this->height);
} elseif ($this->sca_max > 1) { //按某个最大长度缩小
if ($ratio >= 1) { //宽比高长
$newimg = imagecreatetruecolor($this->sca_max, ($this->sca_max / $ratio)); //生成新图片
imagecopyresampled($newimg, $this->tem_file, 0, 0, 0, 0, $this->sca_max, ($this->sca_max / $ratio), $this->width, $this->height);
} else {
$newimg = imagecreatetruecolor(($this->sca_max * $ratio), $this->sca_max); //生成新图片
imagecopyresampled($newimg, $this->tem_file, 0, 0, 0, 0, ($this->sca_max * $ratio), $this->sca_max, $this->width, $this->height);
}
}
} elseif ($this->tag == -1) { //按某个宽度或某个高度缩小
if ($resize_ratio >= 1) {//新高小于新宽,则图片按新宽度缩小
$newimg = imagecreatetruecolor($this->resize_width, ($this->resize_width / $ratio)); //生成新图片
imagecopyresampled($newimg, $this->tem_file, 0, 0, 0, 0, $this->resize_width, ($this->resize_width / $ratio), $this->width, $this->height);
} elseif ($resize_ratio < 1) {//新宽小于新高,则图片按新高度缩小
$newimg = imagecreatetruecolor(($this->resize_height * $ratio), $this->resize_height); //生成新图片
imagecopyresampled($newimg, $this->tem_file, 0, 0, 0, 0, ($this->resize_height * $ratio), $this->resize_height, $this->width, $this->height);
}
}
//输出新图片
if ($this->type == 'jpeg' || $this->type == 'jpg') {
imagejpeg($newimg, $this->des_file);
} elseif ($this->type == 'gif') {
imagegif($newimg, $this->des_file);
} elseif ($this->type == 'png') {
imagepng($newimg, $this->des_file);
} elseif ($this->type == 'bmp') {
imagebmp($newimg, $this->des_file); //bmp.php中包含
}
}
#function new_img() end
}
