Question

I have a web service for iPhone. I receive an image from iPhone in binary form. What I want to ask is can we determine the extension of image being send in binary form.

my code:

$data=base64_decode($data);
$path='event_image/img_out.gif'; /// issue is here
$fp=fopen($path,'w+');
if($fp){ fwrite($fp,$data); fclose($fp); }

Answer 1

Files have signatures http://www.garykessler.net/library/file_sigs.html
You can read from the first line of the file and check.

function output_jpeg($filename)
{
if(($fp = fopen($filename, “rb”)) === false) {
return;
}
$line = fread($fp, 4);
// check the ‘magic number’ of the file
if($line === “\377\330\377\340”) {
fseek($fp, 0);
fpassthru($fp);
}
fclose($fp);
}