Add support for video to audio transcoding

src/FFMpeg/Format/Audio/DefaultAudio.php

@@ -103,4 +103,12 @@ abstract class DefaultAudio extends EventEmitter implements AudioInterface, Prog
 
         return array($listener);
     }
+
+    /**
+     * {@inheritDoc}
+     */
+    public function getPasses()
+    {
+        return 1;
+    }
 }

src/FFMpeg/Format/AudioInterface.php

@@ -19,13 +19,6 @@ interface AudioInterface extends FormatInterface
      */
     public function getAudioKiloBitrate();
 
-    /**
-     * Returns an array of extra parameters to add to ffmpeg commandline.
-     *
-     * @return array()
-     */
-    public function getExtraParams();
-
     /**
      * Returns the audio codec.
      *

src/FFMpeg/Format/FormatInterface.php

@@ -12,4 +12,17 @@ namespace FFMpeg\Format;
 
 interface FormatInterface
 {
+    /**
+     * Returns the number of passes.
+     *
+     * @return string
+     */
+    public function getPasses();
+
+    /**
+     * Returns an array of extra parameters to add to ffmpeg commandline.
+     *
+     * @return array()
+     */
+    public function getExtraParams();
 }

src/FFMpeg/Format/Video/DefaultVideo.php

@@ -86,14 +86,6 @@ abstract class DefaultVideo extends DefaultAudio implements VideoInterface
         return $this;
     }
 
-    /**
-     * {@inheritDoc}
-     */
-    public function getPasses()
-    {
-        return 1;
-    }
-
     /**
      * @return integer
      */

src/FFMpeg/Format/VideoInterface.php

@@ -20,13 +20,6 @@ interface VideoInterface extends AudioInterface
      */
     public function getKiloBitrate();
 
-    /**
-     * Returns the number of passes.
-     *
-     * @return string
-     */
-    public function getPasses();
-
     /**
      * Returns the modulus used by the Resizable video.
      *