Apple Inc. (NASDAQ:AAPL) is working on bringing Siri voice control to Apple TV, 9to5Mac reports.  iOS 7.1's latest software development kit (SDK) suggests that Apple’s mobile personal assistant is getting another level of support for the set-top box.

Indeed, voice recognition is a growing trend in living room media systems. For example, Microsoft Corp.'s  (NASDAQ:MSFT) Xbox One allows users to play media, like movies and television shows, as well as launch applications and search the Web. Apple might be basing its next set-top box off the Xbox Kinect’s voice implementation. Microsoft  has an impressive list of commands that the Xbox One can hear, all of which Apple may implement with a Siri update.

The Apple code, discovered Wednesday, on iOS 7.1 shows three levels of support. Three lines are listed under the UIDeviceFamily in the SDK code: Nos. 1, 2 and 3. No. 1 refers to the iPhone and iPod lines, and No. 2 is the iPad series. That leaves the new line item No. 3 for another device running iOS, which is quite possibly the Apple TV.

Amazon Inc. (NASDAQ:AMZN) earlier this month launched its own set-top box, Amazon Fire TV, that has a voice activation feature that sets it apart from rivals Apple, Roku and Google Inc.’s  (NASDAQ:GOOG) Chromecast. While that may be a novel feature for Amazon, Siri is a complete assistant. The digital PA can add reminders, send messages and set alarms, among other features.

Actor Gary Busey appears in a commercial, touting the benefits of speaking to your television. 

But the question is, how does Apple plan to incorporate Siri into its Apple TV user interface? The Amazon Fire TV has a microphone added into the remote and an activation button. But Apple might have the upper hand with its iOS ecosystem, especially since Apple TV already allows for device mirroring from an iPad, including Siri commands on an iOS device, so a remote might not be too far off.

“Siri, play HBO Go, Game of Thrones, Season 3, episode 3,” might be an easy way of playing content using an iPhone or iPad. Other  features might include directing Siri to download or buy a season pass of a show on iTunes.

The current version of Apple TV supports streaming content from Netflix, Hulu Plus, iTunes and HBO Go, but the set-top box was released in March 2012. Still, if the lines of code identified by 9to5Mac are any indication, the addition of Siri to Apple TV could greatly improve the overall viewing experience. Apple may announce the next version of Apple TV at the WWDC in San Francisco, June 2-6.