Creation of the method to add the filter

src/FFMpeg/Filters/Frame/FrameFilters.php

@@ -36,4 +36,19 @@ class FrameFilters
 
         return $this;
     }
+
+    /**
+     * Fixes the display ratio of the output frame.
+     *
+     * In case the sample ratio and display ratio are different, image may be
+     * anamorphozed. This filter fixes this by specifying the output size.
+     *
+     * @return FrameFilters
+     */
+    public function extractMultipleFrames($frameRate = ExtractMultipleFramesFilter::FRAMERATE_EVERY_2SEC, $destinationFolder = __DIR__)
+    {
+        $this->frame->addFilter(new ExtractMultipleFramesFilter($frameRate, $destinationFolder));
+
+        return $this;
+    }
 }