protected function leadMP4()
	{
		$lead = $this->ffprobeFormat("mp4", "m4a");

		if ($lead === true)
		{
			if ($this->ffprobeHasVideo() !== false)
			{
				return $this->closeCase("mp4", "video/mp4", $this->metadata);
			}
			else if ($this->ffprobeHasAudio() !== false)
			{
				return $this->closeCase("mp4", "audio/mp4", $this->metadata);
			}
			else
			{
				return false;
			}
		}

		return null;
	}
protected function leadMP4()
	{
		$lead = $this->ffprobeFormat("mp4", "m4a");

		if ($lead === true)
		{
			if ($this->ffprobeHasVideo() !== false)
			{
				return $this->closeCase("mp4", "video/mp4", $this->metadata);
			}
			else if ($this->ffprobeHasAudio() !== false)
			{
				return $this->closeCase("mp4", "audio/mp4", $this->metadata);
			}
			else
			{
				return false;
			}
		}

		return null;
	}
protected function leadMP4 ( ) { $ lead = $ this -> ffprobeFormat ( "mp4" , "m4a" ) ; if ( $ lead === true ) { if ( $ this -> ffprobeHasVideo ( ) !== false ) { return $ this -> closeCase ( "mp4" , "video/mp4" , $ this -> metadata ) ; } else if ( $ this -> ffprobeHasAudio ( ) !== false ) { return $ this -> closeCase ( "mp4" , "audio/mp4" , $ this -> metadata ) ; } else { return false ; } } return null ; }
Checks if the file is a MP4.

@return boolean|null
Checks if the file is a MP4 .