Dr Kay Ritchie from the College of Social Science has appeared on BBC’s Crimewatch Roadshow to discuss her work on improving CCTV images using face averages.
Dr Ritchie led a study with psychologists from the University of Lincoln and York, UK, and the University of New South Wales in Australia to create a series of pictures using a ‘face averaging’ technique – a method which digitally combines multiple images into a single enhanced image, removing variants such as head angles or lighting so that only features that indicate the identity if the person remain.
They compared how effectively humans and computer facial recognition systems could identify high quality images, pixelated images, and face averages. The results showed that both people and computer systems were better at identifying a face when viewing an average image that combined multiple pixelated images, compared to the original poor-quality images. Computer systems benefited from averaging together multiple images that were already high in quality, and in some cases reached 100 per cent accurate face recognition. The results have implications for law enforcement and security agencies, where low quality, pixelated images are often the only pictures of suspects available to use in investigations. The image averaging method offers a standardised way of using images captured from multiple CCTV cameras to create a digital snapshot which can be better recognised by both people and computer software systems.
University of Lincoln, College of Social Science Research
Dr Kay Ritchie, Universtiy of Lincoln, School of Psychology