Added check for case when exposure time is already a decimal value.

Author: Marek Szymczuk

lib/PHPExif/Exif.php

@@ -346,6 +346,10 @@ public function getExposureMilliseconds()
             return false;
         }
 
+        if (is_float($this->data[self::EXPOSURE])) {
+            return $this->data[self::EXPOSURE];
+        }
+
         $exposureParts = explode('/', $this->data[self::EXPOSURE]);
 
         return (int) reset($exposureParts) / (int) end($exposureParts);

tests/PHPExif/ExifTest.php

@@ -219,10 +219,19 @@ public function testGetExposure()
      */
     public function testGetExposureMilliseconds()
     {
-        $expected = 1/320;
-        $data[\PHPExif\Exif::EXPOSURE] = '1/320';
-        $this->exif->setData($data);
-        $this->assertEquals($expected, $this->exif->getExposureMilliseconds());
+        $rawData = array(
+            array(1/300, '1/300'),
+            array(0.0025, 0.0025),
+        );
+
+        foreach ($rawData as $data) {
+            $expected = reset($data);
+            $value = end($data);
+
+            $data[\PHPExif\Exif::EXPOSURE] = $value;
+            $this->exif->setData($data);
+            $this->assertEquals($expected, $this->exif->getExposureMilliseconds());
+        }
     }
 
     /**