As most in the video surveillance
traditional video surveillance
an inherent flaw: blind
spots. For example, if a fixed field-ofview
camera is pointed left and an incident
occurs on the right, then the camera
is useless. So, couldn’t we just double or
triple the number of cameras used in every
cafeteria and parking lot in order to
capture every angle? Sure, but then users
are forced to incur extra hardware costs,
installation costs, software licensing and
added maintenance expenses.
With demand for comprehensive security
budgets decrease or stay the same—that
is not a practical solution. This is why
Sentry360 has made obtaining an affordable,
true, 360-degree-view a technology
that is accessible to the masses. Looking
at a pure fisheye image might be a
novel perspective, but when it comes to
a security professional investigating, it
becomes something to decipher. A 360°
fisheye allows the curved fisheye affect
to become corrected, like looking at a
normal camera through a process called
dewarping; however, this is only half the
battle. Let’s put this into context relative
to the current state of the market.
There has been a big boom in the past
few years with manufacturers producing
cameras with fisheye lenses. The reality
is that many of these products came to
market to fill a gap in said manufacturer’s
product-line, which often times is
an imitation not an innovation. Many in
the 360-degree sector believe that all they
have to do to achieve full coverage is attach
a fisheye lens to an IP video camera
and—voila!—they will receive full coverage.
Not so. If you don’t have the ability
to first dewarp then allow full PTZ in live
and recorded 360-degree fisheye images,
then the result is a product that may be
misleading to an end-user.
The majority of these recent entrants
to the fisheye market do allow dewarping
through a common DSP chip manufacturer
Ambarella, but there’s a catch:
The user must dewarp the stream incamera
coming into the VMS which is
typically 20 to 30 percent of the overall
fisheye, leaving 70 to 80 percent unrecorded.
To reduce blind spots, the user
can repeat this process, adding multiple
dewarped streams from the camera at
different angles, but this could, in some
cases, increase bandwidth and storage, or
add software licenses and increase power
consumption from the camera. Throughout
this restricted process, it eliminates
the ability to PTZ the dewarped single
stream view in recorded video, which
should ultimately be the sole purpose for
choosing this breed of technology.
The following will help users understand
best practices, positioning and
applications for this technology with
one common goal: to capture the largest
amount of information with the least
amount of cameras (sensors) from a single
The Application: Ceiling Mount
with 360° Technology
This is the North, South, East and West
approach—with everything in between.
360°cameras are designed to capture a
full half of circle and to be mounted on
the ceiling looking straight down so it
can capture, record and reproduce corrected
perspective PTZ windows in recorded
or live video. The optimization
of the Sentry360 dewarping technology
reduces the amount of total single
field-of-view cameras you will need to
cover heavy traffic or open areas within
schools, banks, retail, assembly lines,
busses, trains, airports and more.
- Mount in a ceiling using a surfacemount
mini dome or flush-mount (discreet
accessory) with a drop ceiling.
- Make a clear decision at what radius
image quality is needed. Think detection
vs. identification. Results will
vary depending on how high the camera
is mounted and how far away the
subject is from the camera.
- Plan for evenly distributed lighting. If
part of environment is poorly lit that
section of the image will be affected.
- Do not mount the 360°camera in a
corner. This reduces its effective coverage.
Ensure the camera is mounted
in intersections or heavy traffic areas
in open spaces.
- Because it’s a 5MP sensor, do not
expect that a dewarped section will
be that same resolution. A single
dewarped view can be, depending on
what native resolution of the camera,
VGA or less, based on how much the
user digitally zooms.
Wall Mount with 180°
This is taking the fisheye and wall mounting
it for a desired 180° viewing angle
(east to west). As opposed to stitching
multiple sensors, for this application, the
fisheye is displayed in one full panoramic
view in your VMS of choice. Users can
then digitally zoom into this view for a
more detailed perspective. Because of the
use of a fisheye and to minimize distortion,
the best portions of the image are
sectioned off for display, and eliminate
the unimportant sections such as the sky,
for example. The panoramic view is intended
to be an overview shot and will
provide users a camera reduction solution
with a single installation point. Applications
include sides of buildings and
parking lots, retail checkout counters,
stairwells, hallways (T intersections) and
- Ensure the 180 is mounted in the middle of the environment, centralizing its perspective view to evenly distribute the image quality throughout the panoramic image.
- Make a clear decision on what mounting height as this effects the overall pixel density of the image.
- For higher mounting, ensure that the 180 has the ability to point downward, either with the outdoor housing or mini-dome lens gimbal, as not to record unnecessary information such as clouds or the ceiling.
- Do not mount the camera where large obstructions can cause blind-spots.
- Do not use this as a replacement for optically-zoomed PTZ for license plate capture. The 180-degree, panoramic view is designed to be an overview scene.
The Application: Table, Counter, Floor and Vehicle 360° Technology
This is using the 360° with a completely different algorithm that we’ve named “InVerted360°,” and could even call for applications users haven’t been thinking about. When mounting the camera on a surface, table, counter or floor looking upward, the perspective changes. In a conference room, for example, you can navigate to the speaker or presenter and interact with others in the meeting room while being on a remote connection. In a retail or cash counting application by mounting or embedding the camera in the counter, users get a closer, more interactive perspective. It even has applications in gaming tables for blackjack or poker to have a table-level perspective of the full interaction between players and dealers.
To deliver the full functionality of 360° fisheye technology, Sentry360 has developed a software development kit (SDK) customized for VMS developers and NVR manufacturers. IP video surveillance has evolved into an ecosystem that allows the users to choose best-in-breed technologies to create a full, customized solution for the end-user, based on their application. Over the years, we were forced to adapt our SDK to work within a variety of different software environments, languages and operating systems. To date, we feel that our SDK is the most integrated, flexible and customizable, enabling the future of this technology to not be limited. We boast that our SDK works with any operating system and software platform/language, and is ready to scale with any resolution as fisheye lenses improve and Ultra-HD becomes more common place.
The Sentry360 SDK has given security providers the tools necessary to record and display the full 360° fisheye image, and then in live or playback, correct the view for a full retrospective PTZ in all directions. The point of 360 is to enable that PTZ experience with the ability of hindsight in full 360 degrees, all while providing full situational awareness.
With nearly 30 technology integrations to date, Sentry360 has laid the ground work to optimize the future of this technology and has laid a path for future quality improvements for scaling in resolution and compression while opening the door to new applications.