Researchers Achieve HD Domestic Spy Video Streaming at 10,000 Less Power
So That Every Watch and Mini-Bug Can Watch You In HD
FROM: Sarah McQuate
University of Washington
Researchers achieve HD video
streaming at 10,000 times lower power
Wearable cameras such as Snap
Spectacles promise to share videos of live concerts or surgeries
instantaneously with the world. But because these cameras must use
smaller batteries to stay lightweight and functional, these devices
can’t perform high-definition video streaming.
Now, engineers at the University
of Washington have developed a new HD video streaming method that doesn’t
need to be plugged in. Their prototype skips the power-hungry parts and
has something else, like a smartphone, process the video instead.
They do this using a technique
called backscatter, through which a device can share information by
reflecting signals that have been transmitted to it.
“The fundamental assumption
people have made so far is that backscatter can be used only for low-data
rate sensors such as temperature sensors,” said co-author Shyam Gollakota
an associate professor in the UW’s Paul G. Allen School of Computer
Science & Engineering. “This work breaks that assumption and shows
that backscatter can indeed support even full HD video.”
In today’s streaming cameras, the
camera first processes and compresses the video before it is transmitted
via Wi-Fi. These processing and communication components eat a lot of
power, especially with HD videos. As a result, a lightweight streaming
camera that doesn’t need large batteries or a power source has been out of
The UW team developed a new
system that eliminates all of these components. Instead, the pixels in the
camera are directly connected to the antenna, and it sends intensity
values via backscatter to a nearby smartphone. The phone, which doesn’t
have the same size and weight restrictions as a small streaming camera,
can process the video instead.
For the video transmission, the
system translates the pixel information from each frame into a series of
pulses where the width of each pulse represents a pixel value. The time
duration of the pulse is proportional to the brightness of the pixel.
“It’s sort of similar to how the
cells in the brain communicate with each other,” said co-author Joshua Smith
a professor in the Allen School and the UW Department of Electrical
Engineering. “Neurons are either signaling or they’re not, so the
information is encoded in the timing of their action potentials.”
The team tested their idea using
a prototype that converted HD YouTube videos into raw pixel data. Then
they fed the pixels into their backscatter system. Their design could
stream 720p HD videos at 10 frames per second to a device up to 14 feet
“That’s like a camera recording a
scene and sending the video to a device in the next room,” said co-author
and computer science and engineering doctoral student Mehrdad Hessar
The team has also created a
low-resolution, low-power security camera, which can stream at 13 frames
per second. This falls in line with the range of functions the group
predicts for this technology.
“There are many applications,”
said co-author and recent UW electrical engineering alum Saman Naderiparizi
“Right now home security cameras have to be plugged in all the time. But
with our technology, we can effectively cut the cord for wireless
The group also envisions a world
where these cameras are smart enough to only turn on when they are needed
for their specific purpose, which could save even more energy.
Gollakota is excited the UW
research team is at the forefront of the low-power video-streaming field
and its impact on the industry.
"This video technology has the
potential to transform the industry as we know it. Cameras are critical
for a number of internet-connected applications, but so far they have been
constrained by their power consumption," he said.
"Just imagine you go to a
football game five years from now," Smith added. "There could be tiny HD
cameras everywhere recording the action: stuck on players’ helmets,
everywhere across the stadium. And you don’t have to ever worry about
changing their batteries."
This technology has been licensed
to Jeeva Wireless
a Seattle-based startup founded by a team of UW researchers, including
Gollakota, Smith and Vamsi Talla, a recent UW alum and co-author on this
This research was funded by the
National Science Foundation, the Alfred P. Sloan Foundation and Google
Faculty Research Awards.