To gain access to image metadata, you must first load the image with a server-side language. You can dynamically load the image in any way you please, including the methods I’ve shown in the past: the only condition is that PHP must be able to address the image file. Here, to make things clearer, I’ll use the image’s filename directly, rather than using a variable.

From PHP’s perspective, IPTC metatags are secreted in the getimagesize function. To make this information visible, we’ll create an array, fill it with getimagesize data, and then use print_r to make the keys of the array visible (I’ll wrap the print_r in a <pre> to format the array in a more presentable fashion:

1. <?php $picinfo = array();
2. getimagesize('lighthouse_spain.jpg', $picinfo);
3. echo "<pre>";
4. print_r(array_keys($picinfo));
5. echo "</pre>"; ?>

The result of our print_r will be somewhat obfuscated:

1. Array (
2. [0] => APP1
3. [1] => APP12
4. [2] => APP13
5. [3] => APP14
6. )

What you need to know is that the ITPC information lies within that third slot. “APP13” is an array unto itself; we could see its contents by using the itpcparse function, and then printing the results out:

1. if(isset($picinfo['APP13']))
2. { $iptc = iptcparse($picinfo['APP13']);
3.     print_r($iptc);
4. }

Now we’re getting somewhere. I’ll show just the relevant parts of the array:

1. Array (
2. [2#105] => Array
3.    ([0] => Lighthouse at dusk in Asturias, Spain)
4. [2#080] => Array
5.    ([0] => René González) 
6. [2#055] => Array
7.    ([0] => 20111016)
8. [2#090] => Array
9.    ([0] => Asturias) 
10. [2#101] => Array
11.    ([0] => Spain)
12. )

This matches the information that we entered into the image in PhotoShop. Now we just need some PHP to extract it and put the results into variables, with a little help from the substr, date, and mktime functions:

1. if(isset($picinfo['APP13']))
2. {
3. $iptc = iptcparse($picinfo["APP13"]);
4.  if (is_array($iptc)) {
5. $description = $iptc['2#105'][0];
6.     $time = $iptc['2#055'][0];
7.     $year = substr($time, 0, 4);
8. $month = substr($time, 4, 2);
9. $day = substr($time, -2);
10. $datetaken = date('l F jS Y', mktime(0, 0, 0, $month, $day, $year));
11. $city = $iptc["2#090"][0];
12. $country = $iptc["2#101"][0];
13. $creator = $iptc["2#080"][0];
14. }

Now we can caption any image read this way with the following information. (Here I’ve gone back to assuming we can address the image itself with a variable.)

1. <figure>
2. <img src="<?=$image?>px;" alt="<?=$description?>" title="<?=$description?>" />
3. <figcaption>
4. <?=$description?>. Taken by <?=$creator?> on <?=$datetaken?>
5. </figcaption>
6. </figure>