“Watching the Watchers,” Operator Performance.
Hina Keval, University College London Human Centered Systems
Spring 2006 Seminar & Exhibition – “CCTV Imagine.” Liverpool Marriot South: Tuesday 4th April 2006.
Overview of talk
•
•
•
•
•
•
PhD Focus
Describe research problem(s)
Report on security control room field work
Summarise research findings
Future directions for my PhD
Question and answers
2
Overview of Research Focus
•
•
•
Previous work: “Does CCTV deter/reduce crime?”
e.g. McCahill (2002) Gill (2005)
Privacy and data protection issues highlighted
My research takes user-centered approach to assessing effectiveness CCTV
Questions: “It is usable? It is effective, efficient
& can we achieve high performance?”
(1) Modern Control Rooms (2) Video Quality for post-recorded CCTV
3
Motivation …
1. My background in ergonomics – improve
systems -> increase usability…
2. CCTV is timely project (9/11, July bombings)
3. Increase in funding in CCTV (public & private)
4. Technology developing fast (analogue to digital)
5. Gap in literature about assessing CCTV
technology with end-users
4
My Approach
•
Home Office Scientific Development Branch (HOSDB)
– Operational Requirements (Aldridge, 1993)
– Covers analogue systems not digital systems
– More specific requirements for video quality needed
– Risk analysis needed
Stakeholder Risk Analysis Approach:
Identify stakeholders, goals & tasks
assess risks and conflicts
5
Stakeholder Risk Analysis Approach
ENVIRONMENT
USER
SYSTEM
Budgets
££
GOALS
Environment:
-Public or Private?
-Pub/club, casino, hotel
-Indoor, outdoor
-Weather impact
User:
-Local authority, private business
owners, police...
System:
Analogue, digital, value, capabilities...
TASKS
Goals:
-What owners want to achieve
Tasks:
-What users required to do
6
CCTV Control Room - Field Work
Objectives:
• Understand processes, tasks, technology used, structure
• To identify operator problems with tasks & technology:
assess performance
Activities
Visited 5 London Borough Control Rooms
Interviewed 5 control room managers & 26 operators
7
Field Work - interviews
Some observations permitted, 26 operators were interviewed:
–
Please describe your role as a control room operator
–
What hours of work are you assigned? Are you happy with your
working hours?
–
What tasks & activities do you carry out on a day-to-day basis?
–
Tell me exactly how you do your work?
–
Does this control room use analogue or digital technology?
–
What tools do you use to help you carry out your tasks?
–
What problems have you found with the technology you use?
8
Control Room Characteristics…
Control
Room
A
Operator
Camera
Ratio
19:160
Technology
Employed
Security Centre
Manager’s Goal(s)
Most Crime Observed
in Control Room
Traffic
enforcement &
surveillance
Shoplifting, assault,
noise, ASBO (Anti
Social Behavioural
Orders) violated
Monitor incidents
and crime
Teenage ‘hoody’ bike
gangs – mobile phone
theft, assault
Digital
Prevent crime and
protect the public
Theft, club/pub late
night knife incidents &
drug taking in car
parks
Digital
Review images on
behalf of police
Hard drug use &
supply, late night
drinking and violence
Provide council
support &
surveillance
Violence, illegal
rubbish/car dumping
& theft
Digital &
Analogue
(50%:50%)
B
C
D
6:110
3:90
6:111
Analogue
Digital & Analogue
E
23:200
(70%:30%)
9
Survey of Operator Tasks
• RESPOND TO REQUESTS – cued information
- radio calls from various groups (businesses, LA, police
force, PCSO’s)
- Respond to neighbourhood problems via telephone
- Responding to email enquiries from LA
• MONITORING OF CAMERAS
- Monitoring CCTV camera activity
- Monitoring traffic enforcement cameras
• ADMINISTRATION WORK
– Tape labelling and preparing copies for police
– Creating incident reports
10
Operator Performance Issues
•
-
CAN’T SEE
Street cameras poorly sited
Signal loss – microwave transmission & bad weather
PTZ controls didn’t work – created ‘embarrassment’
when sharing imagery with police
•
-
TOO MUCH INFO
Low operator to screen ratio
Information overload – too much going on, too many
communication systems, noise, activity
•
-
WORK ORGANISATION ISSUES
“We’re too busy for lunch breaks”… “CCTV is
priority.” Poor social & work set-up = fatigue
11
Barriers to task: Search and select camera
•
•
•
•
•
Majority of operators don’t live in surv. area
All control rooms visited – no maps linked to cams
Staff drew their own maps for newcomers
Need to memorise camera locations, numbers & screens
Paper maps can go astray & need updating
2. Map of Area i.e Camden
with Cameras No.
1. Cameras Database
Search for Camera/Street Location
1
4
2
1
11
3
5
12
7
6
9
10 8
13
12
Camera Number 10 – Gower Street
13
Conclusions & Recommendations
• Crucial existing technologies linked well - best support operator tasks
• Simple solutions i.e. visual maps connected to database & monitor
views allow for faster/efficient way of search
• Regular breaks, standard hours of work balanced with operators no’s
matched with workload
Early findings published:
H.U.Keval and M.A.Sasse. “Man or Gorilla? Performance Issues with CCTV
Technology in Security Control Rooms,” to be presented at the 16th World Congress
on Ergonomics Conference, Maastricht, Netherlands, International Ergonomics
Association, 10-14 July, 2006.
Future visits are planned – Open participation for control room managers
Please sign up!
14
Metropolitan Police (Heathrow Airport command & control room)
• Spent 10 hours observing work and activities at Heathrow
• Visited the Hendon Control Room – still new and not in
operation
• Looked at the workplace equipment layout and functions
• Compared two centres and identified potential usability
problems, made severity ratings and provided
recommendations:
Heathrow Control Room
Hendon Control Room
15
Technology Used
– Police radios
– Telephones
– Computer Aided Dispatch systems (intelligent
systems linked to Scotland Yard)
– Logging information systems
– ANPR (Automatic Number Plate Recognition)
systems
– CCTV monitors
– Sky News TV screen
– Alarm systems (airport alert)
16
HCI Problems Identified
1. CONTROL ROOM AUDIO TRIGGERED NOT VIDEO TRIGGERED
- Potential cognitive overload from radio
- Excessive audio input could be managed based on priority
- Confusion when various alarms ring, affecting task flow
2. DEVICE USAGE
Touch screen & mouse input used together for 1 system
- Bad ergonomics practice -> Health & safety issues
- Too many input devices
- Colour code devices? Use selection switch/pre-selects
3. EXCESSIVE SCREENS
- Too many screens
- Supervisors couldn’t see operators
- Overload of information input
- Merge systems? Use pre-selects
17
Field Work Conclusions
•
•
•
•
•
Technology changing – need for assessment
More investments in CCTV (digital)
Lack of system integration
Poorly linked with human resources (no.) & skills
Design should be focussed on the operator tasks not the technology
“If only 1% of the hardware budget is spent on requirements analysis &
designing for usability, you can probably get 2x as much performance out
of the system.” Prof Sasse (UCL).
Overall Contribution:
Usability framework to improve
control room design
18
Future Directions
•
Empirical work – assessing observation task performance when post-recorded
digital CCTV video quality is poor - 2 tasks face identification & number plate
verification
(1) Which compression schemes suitable?
i.e. MPEG-4 vs Wavelet
(2) At what compression level?
•
“Biggest problem in reality with
The CCTV footage we get is
reading faces & number plates.”
[Claire Summers Digital Video
Expert, Metropolitan Police labs
October 2005].
Contribution:
– Provide users with ideal compression settings for CCTV
– Useful for design & implementation for digital systems
– Useful for automated surveillance: detection & retrieval
19
References
Aldridge J. [1994]. CCTV Operational Requirements Manual Version 3, Home Office, Police Scientific
Development Branch (PSDB), report no. 19/94.
Gill, M, Allen, A, Jessiman, J, Swain, D, Hemming, M, Kara, D, and Little, R. [2005], "Methods in assessing
the impact of CCTV", report no 17, Home Office, Police Scientific Development Branch (PSDB), UK.
McCahill, M and C Norris. [2002], "Literature Review (Working Paper No.2), in on the Threshold to Urban
Panopticon? Analysing the Employment of CCTV in European Cities and Assessing Its Social and Political
Impacts. Berlin: Technical University Berlin: European Commission.
Acknowledgements
Peter Fry, all control room managers so far participated academic advisors
(Prof. Angela Sasse) and also:
20
Thank you for your attention, questions…..
21