Minimum Requirements for Taxicab Security Cameras


Problem: The homicide rate of taxicab-industry is 20 times greater than that of all workers. A NIOSH study showed that cities with taxicab-security cameras experienced significant reduction in taxicab driver homicides. Methods: Minimum technical requirements and a standard test protocol for taxicab-security cameras for effective taxicab-facial identification were determined. The study took more than 10,000 photographs of human-face charts in a simulated-taxicab with various photographic resolutions, dynamic ranges, lens-distortions, and motion-blurs in various light and cab-seat conditions. Thirteen volunteer photograph-evaluators evaluated these face photographs and voted for the minimum technical requirements for taxicab-security cameras. Results: Five worst-case scenario photographic image quality thresholds were suggested: the resolution of XGA-format, highlight-dynamic-range of 1 EV, twilight-dynamic-range of 3.3 EV, lens-distortion of 30%, and shutter-speed of 1/30 second. Practical Applications: These minimum requirements will help taxicab regulators and fleets to identify effective taxicab-security cameras, and help taxicabsecurity camera manufacturers to improve the camera facial identification capability.

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Zeng, S. , Amandus, H. , Amendola, A. , Newbraugh, B. , Cantis, D. and Weaver, D. (2014) Minimum Requirements for Taxicab Security Cameras. Journal of Transportation Technologies, 4, 216-255. doi: 10.4236/jtts.2014.43022.

Conflicts of Interest

The authors declare no conflicts of interest.


[1] NIOSH (2001) Fatal Injuries to Civilian Workers in the United States, 1980-1995. DHHS (NIOSH) Pub. No. 2001-129S.
[2] Bureau of Labor Statistics-Industry (2012) Census of Fatal Occupational Injuries Charts, 1992-2011 (Preliminary Data), All Charts, Census of Fatal occupational Injuries, 2011. Bureau of Labor Statistics.
[3] Bureau of Labor Statistics-Transportation (2012) 2011 Census of Fatal Occupational Injuries (Preliminary Data), Occupation by Transportation Incidents and Homicides, 2011. Bureau of Labor Statistics.
[4] Menendez, C.C., Amandus, H.E., Damadi, P., Nan, W., Konda, S. and Hendricks, S.A. (2013) Effectiveness of Taxicab Security Equipment in Reducing Driver Homicide Rates. American Journal of Preventive Medicine, 45, 1-8.
[5] Moracco, K.E., Runyan, C.W., Loomis, D.P., Wolf, S.H., Napp, D. and Butts, J.D. (2000) Killed on the Clock: A Population-Based Study of Workplace Homicide, 1977-1991. American Journal of Industrial Medicine, 37, 629-636.<629::AID-AJIM7>3.0.CO;2-7
[6] Peek-Asa, C., Howard, J., Vargas, L. and Kraus, J.F. (1997) Incidence of Non-Fatal Workplace Assault Injuries Determined from Employer’s Reports in California. Journal of Occupational and Environmental Medicine, 39, 44-50.
[7] Peek-Asa, C., Schaeffer, K.B., Kraus, J.F. and Howard, J. (1998) Surveillance of Non-Fatal Workplace Assault Injuries, Using Police and Employers’ Reports. Journal of Occupational and Environmental Medicine, 40, 707-713.
[8] Peek-Asa, C., Erickson, R. and Kraus, J.F. (1999) Traumatic Occupational Fatalities in the Retail Industry, United States 1992-1996. American Journal of Industrial Medicine, 35, 186-191.<186::AID-AJIM10>3.0.CO;2-4
[9] Hashemi, L. and Webster, B.S. (1998) Non-Fatal Workplace Violence Workers’ Compensation Claims (1993-1996). Journal of Occupational and Environmental Medicine, 40, 561-567.
[10] Richardson, S. and Windau, J. (2003) Fatal and Nonfatal Assaults in the Workplace, 1996 to 2000. Clinics in Occupational and Environmental Medicine, 3, 673-689.
[11] OSHA (2000) Risk Factors and Protective Measures for Taxi and Livery Drivers. U.S. Department of Labor.
[12] Menendez, C.C. (2012) Taxicab Driver Safety. Proceedings of International Association of Transportation Regulators 2012 Conference, Washington, DC, 15-17 November 2012.
[13] Ramzan, S. and Christian, A. (2007) Report of the Sheffield Taxi Safety Camera Pilot Study. Sheffield Taxi Camera Safety Project 1. Sheffield City Council, Neighbourhoods and Community Care Directorate, Regeneration and Partnership, Policy Support Unit, February 2007.
[14] Harries, L. and Kozubal, J. (2004) Camera Effective in Reducing Taxicab Crime. Proceedings of the 17th Annual International Conference of the International Association of Transportation Regulators, Charleston, September 2004.
[15] Tasmania (2004) Taxi Industry Amendment (Security Cameras) Regulations, Tasmania, Australia, 2004.
[16] New South Wales (2006) Queensland Taxi Security Camera Specifications. Queensland, Australia, January 2006.
[17] New South Wales (2007) NSW Taxi Driver Guide to a Safer Workplace. New South Wales, Australia.
[18] Victoria (2001) Victorian Taxi-Cabs Security Camera Specifications. Victoria, Australia.
[19] New York (2000) Taxi Cab Notes 4.23.2000 v1.b. Taxi & Limousine Commission (New York, NY, USA) March 2000 Press Release, Industry Notice #00-08.
[20] City of Portland, OR (2003) Working Draft, Camera Needs and Wants Matrix Prescriptive Specification. City of Portland, Oregon, USA, 17 October 2003.
[21] New South Wales (2007) Taxi Industry Safety and Security Taskforce Final Report. New South Wales, Australia, December 2007.
[22] VerifEye (2009) Image Comparison Summaries. VerifEye Technologies Inc., Markham.
[23] Honeywell (2009) Mobile Surveillance System. FAREVIEW Series, Honeywell Video Systems, Louisville.
[24] Raywood (2009) Raywood SnapShot® Cameras. Raywood Communications Inc., Houston.
[25] VerifEye (2009) TaxiCamTM Mark IV. VerifEye Technologies Inc., Markham.
[26] Point Grey (2010) Grasshopper® Technical Reference Manual. Version 1.5. Point Grey Research.
[27] Ray, S.F. (2000) Camera Exposure Determination. In: Jacobson, R.E., Ray, S.F., Atteridge, G.G. and Axford, N.R., Eds., The Manual of Photography, Focal Press, Oxford, 310-318.
[28] Bockaert, V. (2009) The 123 of Digital Imaging Interactive Learning Suite, Version 5.0, Chapter 1. Understanding Digital Imaging (DI).
[29] Butler, R. (2009) Nikon D5000 Review. Digital Photography Review. 18 June 2009.
[30] DxO Labs (2010) Lens Distortion. DxO Labs.
[31] Schlyter, P. and Sweden, S. (2006) Radiometry and Photometry in Astronomy.
[32] Imatest (2013) Sharpness: What Is It and How Is It Measured.
[33] ANSI (2007) American National Standard for Safe Use of Lasers. Z136.1. ANSI, Tables 5a, and 6, 74-76.
[34] Hahn, G.J. and Meeker, W.Q. (1991) Statistical Intervals: A Guide for Practitioners, John Wiley & Sons, New York.
[35] SAS Institute Inc. (2009) SAS 9.2 Help and Documentation. SAS Institute Inc., Cary.
[36] Human Factors Standardization (2000) Human Engineering Design Data Digest. Human Factors Standardization Subtag, Human Factors Engineering Technical Advisory Group, Department of Defense, April 2000, 75, USA.
[37] Australian CCTV Standard (2006) Australian Standard® Closed Circuit Television (CCTV), Part 2: Application Guidelines, AS 4806.2-2006. Australia, 19-20.
[38] Ramanath, R., Snyder, W., Bilbro, G.L. and Sander, W.A. (2002) Demosaicking Methods in Bayer Color Arrays. Journal of Electronic Imaging, 11, 306-315.
[39] Digital Photography Review (2008) Canon SD1100 IS Digital ELPH (IXUS 80 IS) Concise Review, Digital Photography Review.
[40] Fellers, T.J. and Davidson, M.W. (2005) Concepts in Digital Imaging Technology—CCD Saturation and Blooming.
[41] Myszkowski, K., Mantiuk, R. and Krawczyk, G. (2008) High Dynamic Range Video. 1st Edition, Morgan & Claypool, San Rafael.

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