We've tracked down another video of the upcoming, all-new 2016 Toyota Prius testing on public roads.

A San Francisco driver captured video of what appears to be a camouflaged Prius prototype on one of the city's typically hilly streets.

The car appears similar to other apparent Prius test vehicles captured in public over the past few months.

DON'T MISS: 2016 Toyota Prius: Latest Spy Shots

The next-generation Prius is expected to make its public debut sometime this fall, whether at an auto show or in a separate event.

It's the fourth generation of the world's bestselling hybrid, with over 5 million vehicles sold since the Prius first went on sale in Japan in 1997.

As with previous spy footage, this video--shot by YouTube user J Liu--shows that the new fourth-generation Prius will largely adhere to the styling conventions established by the second-generation model, which debuted in 2004.

2015 Toyota Prius Liftback

2015 Toyota Prius Liftback

That means a smooth five-door hatchback body, with a steeply-raked windshield and a truncated high Kamm tail for for minimal wind resistance and good airflow.

However, it's been widely reported that the next Prius will also feature sportier styling, to help it appeal to a wider range of buyers.

A brief shot of a third-generation Prius behind the test car provides some comparison between the new and outgoing designs.

 ALSO SEE: 2016 Toyota Prius Hybrid: Clearer Spy Shot Of High-Tailed Rear

The prototype car's camouflage makes it hard to draw any definitive conclusions, but its nose and front hood line appear to be lower than the current model.

There's also little that we know for sure about the car's powertrain, although Toyota has made some impressive boasts.

At a technical conference earlier this year, the carmaker said it had achieved a peak thermal efficiency of 40 percent from a new gasoline engine under certain conditions.

2012 Toyota Prius Plug-In Hybrid

2012 Toyota Prius Plug-In Hybrid

And at a presentation back in 2013, Toyota indicated that the new model would be at least 10 percent more efficient than the outgoing Prius.

That equates to an EPA combined fuel-economy rating of 55 mpg.

The new powertrain will almost certainly be an updated version of Toyota's longstanding Hybrid Synergy Drive.

MORE: Is This The Next Toyota Prius Hybrid Captured On Video?

All-wheel drive may also become an option on the Prius for the first time.

In addition to the standard Liftback, Toyota will launch a new Prius Plug-In Hybrid, although that version won't appear until next year.

The company has so far been mum on plans for new versions of the other Prius variants--the Prius C subcompact and Prius V tall wagon--although those vehicles debuted two years later than the soon-to-be replaced Liftback.

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