/**
* desription 压缩图片
* @param sting $imgsrc 图片路径
* @param string $imgdst 压缩后保存路径
*/
public function compressedImage($imgsrc, $imgdst) {
list($width, $height, $type) = getimagesize($imgsrc);
$new_width = $width;//压缩后的图片宽
$new_height = $height;//压缩后的图片高
//$new_width = ($width>600?600:$width)*0.9;
//$new_height =($height>600?600:$height)*0.9;
switch ($type) {
case 1:
$giftype = $this->check_gifcartoon($imgsrc);
if ($giftype) {
header('Content-Type:image/gif');
$image_wp = imagecreatetruecolor($new_width, $new_height);
$image = imagecreatefromgif($imgsrc);
imagecopyresampled($image_wp, $image, 0, 0, 0, 0, $new_width, $new_height, $width, $height);
//90代表的是质量、压缩图片容量大小
imagejpeg($image_wp, $imgdst, 90);
imagedestroy($image_wp);
imagedestroy($image);
}
break;
case 2:
header('Content-Type:image/jpeg');
$image_wp = imagecreatetruecolor($new_width, $new_height);
$image = imagecreatefromjpeg($imgsrc);
imagecopyresampled($image_wp, $image, 0, 0, 0, 0, $new_width, $new_height, $width, $height);
//90代表的是质量、压缩图片容量大小
imagejpeg($image_wp, $imgdst, 90);
imagedestroy($image_wp);
imagedestroy($image);
break;
case 3:
header('Content-Type:image/png');
$image_wp = imagecreatetruecolor($new_width, $new_height);
$image = imagecreatefrompng($imgsrc);
imagecopyresampled($image_wp, $image, 0, 0, 0, 0, $new_width, $new_height, $width, $height);
//90代表的是质量、压缩图片容量大小
imagejpeg($image_wp, $imgdst, 90);
imagedestroy($image_wp);
imagedestroy($image);
break;
}
}
/**
* desription 判断是否gif动画
* @param sting image_file图片路径
* @return boolean t 是 f 否
*/
public function check_gifcartoon($image_file){
$fp = fopen($image_file,'rb');
$image_head = fread($fp,1024);
fclose($fp);
return preg_match("/".chr(0x21).chr(0xff).chr(0x0b).'NETSCAPE2.0'."/",$image_head)?false:true;
}
来源：https://www.cnblogs.com/Mr-zhangwenqiang/p/11935873.html