Apple is expected to unveil updated iPhones Wednesday along with an Apple TV revamp that may signal a push into online television streaming dominated by Netflix.

Apple remained mum even as rumors ran rampant about what is in store at the San Francisco media event.

In trademark enigmatic style, invitations provided little more than the time and place of the event, to be held at the spacious Bill Graham Civic Auditorium near city hall.

A line on the invite reading: "Hey Siri, give us a hint," led many to believe that virtual assistant software Siri, which is built into Apple devices, will help people find shows or movies on Apple TV.

Apple TV is also believed to be getting its own App Store, which will be open to outside developers who can make games and other content for it.

The third-generation Apple TV was introduced slightly more than three years ago. The California-based company long downplayed Apple TV as a "hobby" after the original version was released in 2007.

"They are finally revisiting their hobby, the Apple TV," said Forrester analyst Frank Gillett.

Apple is dabbling with the idea of making online television programming in a move that would challenge established players such as Netflix and Amazon Prime, according to a recent report in show-business magazine Variety.

"There is a definite movement toward cord-cutting, and Apple is in position to do that," said Gartner analyst Van Baker.

"They have the premium content lined up, so the real differentiator is to bring network television to the platform."

- Keys to the kingdom -

"Original programming is the only solution to Apple's biggest problem in the video world: nobody wants to sell Apple content rights" said Forrester analyst James McQuivey.

"After watching what happened to the music business when Apple was given the keys to the kingdom, video producers and programmers are more than gun shy about handing the same power to Apple in the world of TV shows."

Apple became a power to be reckoned with in digital music sales due to the popularity of its mobile devices and iTunes online shop.

While Apple was at the forefront of the shift to digital music, the world of Internet-streamed television already has powerful players.

"Apple's opportunity to shape the market is gone, they're just joining this program already in progress," McQuivey said.

Data gathered by Forrester indicated that 19 percent of US adults who use the Internet are interested in or use Apple TV. That percentage jumps to nearly a third when it is limited to online adults ranging from age 27 to 35.

While bringing Siri to Apple TV would be noteworthy, the analyst did not see that alone as being enough to get people to rush out and buy the hardware.

"Siri hasn't taken over the phone and it won't take over the TV either," McQuivey said.

"In the case of TV it's because there really aren't things other than search that voice can help with, and you don't need Siri to do voice search."

Amazon's Fire TV products feature an "elegant voice search button that's dead simple to use," he added.

- Speedier iPhones -

An iPhone update unveiling is considered a sure thing at the media event, since the company has a pattern of doing just that every September.

"We are going to get the iPhone 6S and iPhone 6S Plus, or whatever they are going to call it," predicted Gartner analyst Baker.

Improvements are expected to include faster processing and better cameras, with Apple having made photography a strong part of its offering, according to Baker.

New iPhone models might also feature "force touch" technology used in Apple Watch, which allows the user to control the device based on how hard the screen is pressed.

Weaker speculation has Apple introducing a new, bigger iPad in what would be a break from the company's tradition of unveiling tablet news at a separate event in October.

"If rumors of a large iPad play out, they may be showing us a new vision for what iPads are in our lives," said Forrester analyst Gillett.

Apple's decision to stage the event in a venue with a capacity to hold 7,000 people has prompted some to suspect that a surprise is in store.

"It makes me think there is a little more -- they need elbow room for something," Gillett said.

Perhaps, he speculated, there will be a "Trojan Horse in Apple TV," allowing it to control smart gadgets in homes.