The online retailer added a service to its Amazon Web Services portfolio designed to aid content providers. Called Amazon Elastic Transcoder, it transcodes video files between different digital media formats. Users can convert large master video files to smaller versions for playing on websites, connected TVs and mobile devices like smartphones and tablets. Amazon (AMZN) sees the service used to create enterprise, user-generated, broadcast and other content for apps or websites. Shares dropped 5.7% to 260.35.