Bunnie Huang
COLUMN
SPARK
ne of my favourite
aspects of the Raspberry
Pi is its rich ecosystem
of applications. A good
example of this is
Alasdair Allan’s demo
(hsmag.cc/MXDCSf), combining a magic
mirror and Google AIY to create a voice-
activated home assistant. I especially like
the mix because then I don’t have to listen
to the long-winded responses of audio-
only home assistants. This example really
shows off the Pi’s application ecosystem.
One downside of the magic mirror is
the need to dedicate a whole screen to
the application.
Even if you had a
spare TV laying
around, finding a
spot to put it, and
wrapping it in
a custom frame
can take a lot of
time and effort.
Wouldn’t it be
nice if you could
somehow merge
the magic mirror’s output onto the TV
screen you already have?
Fortunately, there’s a partial solution
to the problem – it’s technically feasible
to encrypt the HDMI video coming
from your Raspberry Pi so the TV can
understand it. Once encrypted, portions
of the screen can be cherry-picked to
come from either the Pi or your existing
home entertainment system. I’ve built a
system called NeTV2 that can do this. It’sbasically a Raspberry Pi HAT that sports
an FPGA, wrapped into a custom plastic
case and, as of the time of publication, it’s
crowdfunding over at hsmag.cc/Hbragk.
Although a programmable video overlay
seems like a blindingly obvious widget
that should be readily available off the
shelf, the manipulation of encrypted data
is legally challenging. You can read more
about the subtle legal challenges on the
Crowd Supply page linked above.
Now, one can technically merge a magic
mirror onto any TV screen by just plugging
NeTV2 in-line with the main video cable
and loading up the application. Combine
it with Google
AIY to make a
voice-activated
home assistant, or
perhaps just open
a small browser
window and
connect to your
baby monitor, or
track how long it
is until your pizza
arrives while
you enjoy the game. These are just a few
examples of what’s made possible with
video overlay, and we’re just starting to
scratch the surface of the possibilities. If
the legal challenges around processing
encrypted video can be resolved, NeTV2
can also power even more exciting
applications, utilising AI on video feeds
to help with everything from real-time
translations to fantasy sports to health and
assistive care.Turn your TV into a
home assistant using
a Raspberry Pi
When legal confusion causes technical problems
Bunnie Huang
Andrew ‘Bunnie’ Huang is a
hacker by night, entrepreneur
by day, and writer by
procrastination. He’s a
co‑founder of Chibitronics,
troublemaker‑at‑large for the
MIT Media Lab, and a mentor
for HAX in Shenzhen.
O
One downside of the
magic mirror is the
need to dedicate
a whole screen to
the application@bunniestudios