Getting Exif information out of Images.

function get_exif($filename, $gallery)
{
	if(!extension_loaded('exif'))
	{
		return "Exif Support Not Loaded";
	}
	else
	{
/* In my gallery code all my images are under the gallery folder, under a specific gallery, the path below can be changed to where you images are located. */
		$imagepath = $_SERVER['DOCUMENT_ROOT']."/gallery/".$gallery."/".$filename.".jpg";
	
	/* next line obtains the exif data from the images the second parameter can be changed to 'EXIF' but seems 'IFD0' works fine for the list of information I need */
		@$exif = exif_read_data($imagepath, 'IFD0');				
/* Because manufacture vary , the exif information provided isnt always in the same name, I check to see if at least two of the exif information is not blank, if they are then I assume no valid exif information is present. */

		if (($exif['FNumber'] == "") || ($exif['FocalLength'] == ""))
			return "No EXIF Data";
		else
		{
			@$exif = exif_read_data($imagepath, 'IFD0', true);

//uncomment the next code block, if you wish to see ALL values inside of the exif information, useful for finding the exact keys you want beforehand
			/*
			foreach ($exif as $key => $section) {
				foreach ($section as $name => $val) {
					echo "<!-- $key.$name: $val -->\n";
				}
			}
			*/

//convert the raw values to understandible values
			$Fnumber = explode("/", $exif['EXIF']['FNumber']);
			$Fnumber = $Fnumber[0] / $Fnumber[1];
			$Focal = explode("/", $exif['EXIF']['FocalLength']);
			$Focal = $Focal[0] / $Focal[1];

//prepare the text for return		
			$exif_text = "Model: ".$exif['IFD0']['Model']."<br>";
			$exif_text = $exif_text."Shutter: ".$exif['EXIF']['ExposureTime']."<br>";
			$exif_text = $exif_text."Aperture: f/".$Fnumber."<br>";
			$exif_text = $exif_text."ISO Speed: ".$exif['EXIF']['ISOSpeedRatings']."<br>";
			$exif_text = $exif_text."Focal Length: ".round($Focal)."mm<br>";
			
			return $exif_text;
		}
	}
}