Add FFProbe#isValid

fixes #394

src/FFMpeg/FFProbe.php

@@ -170,6 +170,25 @@ class FFProbe
         return $this->probe($pathfile, '-show_format', static::TYPE_FORMAT);
     }
 
+    /**
+     * @api
+     *
+     * Checks wether the given `$pathfile` is considered a valid media file.
+     *
+     * @param string $pathfile
+     * @return bool
+     * @since 0.10.0
+     */
+    public function isValid(string $pathfile)
+    {
+        try {
+            return $this->format($pathfile)->get('duration') > 0;
+        } catch(\Exception $e) {
+            // complete invalid data
+            return false;
+        }
+    }
+
     /**
      * @api
      *

tests/Functional/FFProbeTest.php

@@ -12,10 +12,23 @@ class FFProbeTest extends FunctionalTestCase
         $this->assertGreaterThan(0, count($ffprobe->streams(__DIR__ . '/../files/Audio.mp3')));
     }
 
+    public function testValidateExistingFile()
+    {
+        $ffprobe = FFProbe::create();
+        $this->assertTrue($ffprobe->isValid(__DIR__ . '/../files/sample.3gp'));
+    }
+
+
+    public function testValidateNonExistingFile()
+    {
+        $ffprobe = FFProbe::create();
+        $this->assertFalse($ffprobe->isValid(__DIR__ . '/../files/WrongFile.mp4'));
+    }
+
     /**
      * @expectedException FFMpeg\Exception\RuntimeException
      */
-    public function testProbeOnUnexistantFile()
+    public function testProbeOnNonExistantFile()
     {
         $ffprobe = FFProbe::create();
         $ffprobe->streams('/path/to/no/file');