May 2012
Tactical & Practical is a series of communications aimed at educating end users, specifiers, and integrators of new and
innovative ways to deploy security system hardware and software for optimal balance of value and performance.
Bit Rate Analysis Case Study
The goal was to properly estimate video storage
requirements for a prison which required 1080p HD
video at 7.5ips for 90 days. Following meetings with
various manufacturer representatives it was clear to the
prison staff that the storage estimations varied widely.
This presented a challenge to the entire process of
procuring a new surveillance system which will include
approximately 400 cameras capable of delivering 1080p
resolution.
A Bosch Dinion 1080p (NBN-832) camera was used on
a tripod in the prison’s normal lighting conditions. One
exterior scene was captured at mid-day with cloud cover.
Facility regulations do not allow the images to leave the
facility, so for better scene descriptions please feel free
to contact Midlantic Marketing for more information. The
images shown below are similar representations and
ARE NOT from this analysis project.
At 0x digital zoom the images all looked nearly identical
when viewed on a laptop
computer screen, 16:9 on a
Sony VAIO VPCSA with a 17”
screen. The prison will be
examining the images under
various levels of digital zoom
to see where the threshold for
their acceptable bit rate is
based upon image clarity. The
prison staff will decide the bit rates to be used by all
bidders for the storage equation based on the digital
zoom levels deemed to be acceptable to the Warden of
the facility. The camera’s maximum bit rate was left at
the factory default, 10Mbps.
Scene 1 – Hallway - Muted Color Palette – Medium Human Activity
500 kbps target, 7.5ips max 10Mbps, ACTUAL 941 kbps
1mbps target, 7.5ips
max 10Mbps, ACTUAL 1478 kbps
3mbps target, 7.5ips
max 10Mbps, ACTUAL 1444 kbps
6mbps target, 7.5ips
max 10Mbps, ACTUAL 1839 kbps
Scene 2 – Cell Block – No Human Activity
500 kbps target, 7.5ips max 10Mbps, ACTUAL 1985 kbps
1mbps target, 7.5ips
max 10Mbps, ACTUAL 1084 kbps
3mbps target, 7.5ips
max 10Mbps, ACTUAL 1957 kbps
6mbps target, 7.5ips
max 10Mbps, ACTUAL 1970 kbps
Scene 3 – Recreation Yard – High Human Activity
500 kbps target, 7.5ips max 10Mbps, ACTUAL 754 kbps
1mbps target, 7.5ips
max 10Mbps, ACTUAL 1820 kbps
3mbps target, 7.5ips
max 10Mbps, ACTUAL 2363 kbps
6mbps target, 7.5ips
max 10Mbps, ACTUAL 3110 kbps
Scene 4 – Transition Room – Low Human Activity
500 kbps target, 7.5ips max 10Mbps, ACTUAL 523 kbps
1mbps target, 7.5ips
max 10Mbps, ACTUAL 547 kbps
3mbps target, 7.5ips
max 10Mbps, ACTUAL 883 kbps
6mbps target, 7.5ips
max 10Mbps, ACTUAL 887 kbps
Scene 5 – Cell Block – Medium Human Activity
500 kbps target, 7.5ips max 10Mbps, ACTUAL 552 kbps
1mbps target, 7.5ips
max 10Mbps, ACTUAL 1110 kbps
3mbps target, 7.5ips
max 10Mbps, ACTUAL 2864 kbps
6mbps target, 7.5ips
max 10Mbps, ACTUAL 2715 kbps
Scene 6 – Hallway - Medium Color Saturation – Low Human Activity
500 kbps target, 7.5ips max 10Mbps, ACTUAL 640 kbps
1mbps target, 7.5ips
max 10Mbps, ACTUAL 660 kbps
3mbps target, 7.5ips
max 10Mbps, ACTUAL 748 kbps
6mbps target, 7.5ips
max 10Mbps, ACTUAL 1430 kbps
What’s Involved? Bit rate sampling can be as basic or
complex as you desire. The more
images, scenes, and conditions that are
captured the better for limiting the
estimation; however this will require
financial investment.
The sampling
above was conducted in approximately
three hours. Evaluation of the images and consideration
of the data will require additional time. The equipment
required is one camera with the ability to provide real
time bit rates with a live image. You will need a tripod or
stable platform, small PoE network switch, laptop with
any applicable software, multi-outlet power strip with
extension cord, and ability to paste images and type
descriptions into a program such as Microsoft Word.
Other Considerations: When deciding to perform a bit
rate analysis, consider image resolution (4CIF, 720p,
1080p), lighting (night, day, IR illumination), movement
(human or camera), and scene type (colors, scene
complexity, high contrast).
NOTE: Each facility owner must determine their comfort level
with image clarity based upon the bit rate sampling conducted,
ideally, at their facility.
This document is meant for
informational and educational purposes only.
Midlantic
Marketing and Chesapeake Marketing do not any liability
related to use of this document or the data within.
Who can do this? Anyone with the equipment listed
above and the time to commit can perform this analysis.
Familiarity with the equipment will reduce errors and limit
time spent on capturing the data.
Making assumptions on the data above: By using the
information above as well as by comparing high human
motion and no/low human motion more accurate storage
requirement estimation calculations can be completed.
Percentage of motion vs. no/low motion over a period of
time may also be estimated by the owner. Acceptable
image clarity lies in the eye of the beholder; however the
associated bit rate is indisputable with proper data
collection.
Midlantic Marketing and Chesapeake Marketing are independent
sales and marketing groups for many of the security industry’s
finest manufacturers. We serve end users, specifiers, and
integrators from Pennsylvania, Delaware, southern New Jersey,
Maryland, Virginia, and Washington DC.
www.chesapeakemarketing.com
1401 Abingdon Road
Abingdon, MD 21009
410.612.9640
www.midlantic.net
118 Commons Court
Chadds Ford, PA 19317
610.361.0500