Simulate getimagesizefromstring function below php5.4-PHP Tutorial-php.cn

Simulate getimagesizefromstring function below php5.4

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Release： 2016-07-25 08:55:09

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

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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);

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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);