Fastest way to determine image resolution and file type in PHP or Unix command line?

Question

I'm currently using ImageMagick to determine the resolution of images uploaded to the website. By calling ImageMagick's "identify" on the command line it takes about 0.42 seconds to determine a 1MB JPEG's resolution along with the fact that it's a JPEG. I find that a bit slow.

Using the Imagick PHP library is even slower as it attemps to load the whole 1MB in memory before doing any treatment to the image (in this case, simply determining its size and type).

Are there any solutions to speed up this process of determining which file type and which image resolution an arbitrary image file has? I can live with it only supporting JPEG and PNG. It's important to me that the file type is determined by looking at the file's headers and not simply the extension.

Edit: The solution can be a command-line tool UNIX called by PHP, much like the way I'm using ImageMagick at the moment

Answer 1

If you're using PHP with GD support, you can try getimagesize().

Answer 2

It's important to me that the file type is determined by looking at the file's headers and not simply the extension.

For that you can use 'file' unix command (orsome php function that implements the same functionality).

/tmp$ file stackoverflow-logo-250.png
stackoverflow-logo-250.png: PNG image data, 250 x 70, 8-bit colormap, non-interlaced

Answer 3

Have you tried

identify -ping filename.png

?

Answer 4

Actually, to use getimagesize(), you do NOT need to have GD compiled in.

You can also use mime_content_type() to get the MIME type.

Answer 5

Sorry I can't add this as a comment to a previous answer but I don't have the rep. Doing some quick and dirty testing I also found that exec("identify -ping... is about 20 times faster than without the -ping. But getimagesize() appears to be about 200 times faster still.

So I would say getimagesize() is the faster method. I only tested on jpg and not on png.

the test is just

$files = array('2819547919_db7466149b_o_d.jpg', 'GP1-green2.jpg', 'aegeri-lake-switzerland.JPG');
foreach($files as $file){
  $size2 = array();
  $size3 = array();
  $time1 = microtime();
  $size = getimagesize($file);
  $time1 = microtime() - $time1;
  print "$time1 \n";
  $time2 = microtime();
  exec("identify -ping $file", $size2);
  $time2 = microtime() - $time2;
  print $time2/$time1 . "\n";
  $time2 = microtime();
  exec("identify $file", $size3);
  $time2 = microtime() - $time2;
  print $time2/$time1 . "\n";
  print_r($size);
  print_r($size2);
  print_r($size3);
}