Simulate getimagesizefromstring function below php5.4

if($in = fopen('php://input', "rb"))
 while($buff = fread($in, 4096))
 fwrite('e:\1.jpg' , $buff);

To get the image information, the only way is getimagesize($filename) and open the file you just closed again. There is a getimagesizefromstring in php, but it requires >=php5.4.

Is there a way to directly manipulate the data stream? The answer is yes, there is "Supported Protocols and Encapsulation Protocols" in the official PHP manual, and the data:// in it should be familiar to everyone.

You can use it to directly manipulate images (watermarks, thumbnails, etc.) in the data stream. For convenience, the following code is directly 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));//or $new_img = imagecreatefromstring($stream);
print_r($new_img);
imagejpeg($new_img, 'E:WEBuploadstest.jpg', 100);

The format was successfully converted.

This method is good, but base64 doesn't look so cool.

You can consider a simpler method, stream_register_wrapper — register a URL wrapper protocol implemented with a PHP class.

Code:

 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");
< p> print_r(getimagesize('image://stream'));
$new_img = imagecreatefromgif('image://stream');//or $new_img = imagecreatefromstring($stream);
print_r($new_img);
imagejpeg ($new_img, 'E:WEBuploadstest.jpg', 100);

No surprises, because this function supports PHP 4 >= 4.3.0, PHP 5.

After testing, the same local picture (300x800), the average method 1 is 43ms, the average method 2 is 39ms

Correction: If the stream reported by getimagesize does not support seeking, you may need to add the seek operation to the wrapper and add the code:

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 <= $l);
 if($ret)
 $p = $newPos;
 return $ret;
 }