-
- if($in = fopen('php://input', "rb"))
- while($buff = fread($in, 4096))
- fwrite('e:\\1.jpg', $buff);
-
复制代码
要得到图片信息,那只有getimagesize($filename),再打一次刚关闭的文件。
php中有一个getimagesizefromstring,但是要求>=php5.4。
有直接操纵数据流的方法吗?
答案是有, php官方手册上有 "支持的协议和封装协议",其中的data://大家应该都很熟悉.
可以利用它完成在数据流中直接操纵图片(水印,缩略图之类)。
以下代码为了方便,就直接file_get_contents().
-
-
$file_path = 'http://www.baidu.com/img/shouye_b5486898c692066bd2cbaeda86d74448.gif';
- $stream = file_get_contents($file_path);
- print_r(getimagesize("data://text/plain;base64," . base64_encode($stream)));
- $new_img = imagecreatefromgif("data://text/plain;base64," . base64_encode($stream));//或者$new_img = imagecreatefromstring($stream);
- print_r($new_img);
- imagejpeg($new_img, 'E:\WEB\uploads\test.jpg', 100);
-
复制代码
成功转换格式。
这种方法不错,但一次base64看起来不是那么爽。
可以考虑更简单的方法,stream_register_wrapper — 注册一个用 PHP 类实现的 URL 封装协议。
代码:
-
-
class getImgStream{
-
- private $imgStream;
- private $position;
-
- function stream_open($path, $mode, $options, &$opened_path){
- $url = parse_url($path);
- $this->imgStream = $GLOBALS[$url["host"]];
- $this->position = 0;
- return true;
- }
function stream_read($count){
- $ret = substr($this->imgStream, $this->position, $count);
- $this->position += strlen($ret);
- return $ret;
- }
- function stream_stat(){
- //maxmemory: 5 * 1024 * 1024;
- $fp = fopen("php://temp/maxmemory:5242880", 'r+');
- fwrite($fp, $this->imgStream);
- $fstat = fstat($fp);
- fclose($fp);
- return $fstat;
- }
function stream_eof(){
- return $this->position >= strlen($this->imgStream);
- }
function stream_tell(){
- return $this->position;
- }
- function stream_close(){
- unset($this->imgStream, $this->position);
- }
- }
$file_path = 'http://www.baidu.com/img/shouye_b5486898c692066bd2cbaeda86d74448.gif';
- $stream = file_get_contents($file_path);
stream_wrapper_register("image", "getImgStream");
print_r(getimagesize('image://stream'));
- $new_img = imagecreatefromgif('image://stream');//或者$new_img = imagecreatefromstring($stream);
- print_r($new_img);
- imagejpeg($new_img, 'E:\WEB\uploads\test.jpg', 100);
-
复制代码
没有意外,因为这个函数支持PHP 4 >= 4.3.0, PHP 5。
经测试,同一张本地图片(300x800),方法一平均43ms,方法二平均39ms
更正:
如果报getimagesize的stream does not support seeking,可能要在wrapper中加入seek的操作,添加代码:
-
- function stream_seek($offset, $whence){
- $l = strlen($this->imgStream);
- $p = &$this->position;
- switch($whence){
- case SEEK_SET: $newPos = $offset;
- break;
- case SEEK_CUR: $newPos = $p + $offset;
- break;
- case SEEK_END: $newPos = $l + $offset;
- break;
- default: return false;
- }
- $ret = ($newPos >= 0 && $newPos if($ret)
- $p = $newPos;
- return $ret;
- }
复制代码
|