Digital Futures 2009: Image Physics & Psychophysics

A Symposium jointly organised by the Imaging Science Group of The Royal Photographic Society
and the Printing and Graphics Science Group of the Institute of Physics.

Tuesday 3 November 2009,
Institute of Physics, 76 Portland Place, London W1B 1NT

Report by Dr Alan Hodgson ASIS FRPS, 3M Security Printing and Systems Limited

This was the 10th in a series of Digital Futures meetings held by the Royal Photographic Society Imaging Science Group and the second time it had been held as a joint event with the Institute of Physics Printing and Graphics Science Group. The theme for this year was Image Physics & Psychophysics and we were treated to 12 excellent presentations on this subject.

Once again the topics exposed the delegates to a broad spectrum of application areas from medical to video imaging and it was especially good to welcome a large contingent of students, both as audience and presenters. The topics were laid out in 4 blocks to allow for networking and 1:1 questioning of the speakers to take place. We hope to have the permission to upload the presentations in the near future.

Block 1 was focussed on the topic of Image Quality. Ralph Jacobson, Emeritus Professor at Westminster delivered the plenary talk covering the "…nesses" of Image Quality. The Minkowski metrics look particularly interesting. These are multivariate metrics combining 2 quantities in an empirical fashion to fit the observations. They work but as of yet do not have a theoretical basis.

Hani Muammar then covered ISO 20462, a 3-part international standard for the measurement of psychophysical image quality. This is a complex standard covering the even more complex topic of image quality evaluation, documenting the excellent work that has been done by Fujifilm and Kodak.

Geoff Attridge, another Emeritus Professor at Westminster then covered colour image quality with some interesting colour gamut maps of prints and display.

Block 2 started with a couple of excellent student presentations from Kyung-Hoon Oh and Francesco Mancusi on scene classification, illustrating the breadth of work going on at Westminster. There followed a very interesting presentation from Dimitris Mylonas who has just completed an MSc in Digital Colour Imaging at the London College of Communication. His work looked at colour naming in different cultures and looks applicable to some of the work on natural colour names being done at Xerox.

Block 3 began after lunch and began with an interesting psychophysics study on perceived naturalness of surfaces presented by Ruth Montgomery of NPL. The study covered both visual and tactile features on materials such as wood and fabric. The objective measures included surface roughness and a custom built goniometer system.

Ana Tsifouti is based at the Home Office Scientific Development Branch and is doing a part time PhD at Westminster. Her presentation covered video recording systems and the effect of frame rate and compression on image usefulness. Finally in this session it was good to welcome back Hoosain Ebrahim from the University of Limpopo in South Africa. His presentation featured image quality evaluation of medical photographs.

Block 4 started with a presentation from Steve Collins at University of Oxford on high dynamic range pixel technology, showing different ways in which the electronics in CMOS technology can be adapted to this end. The techniques work well for higher illumination levels but as expected struggle with lower light conditions. Philip Bateman, a student from the University of Surrey then provided an excellent presentation on the potential of statistical process control techniques for camera identification. He concluded that this technique can be successfully be used to model the behaviour of the image acquisition process in a digital camera. Finally there was a presentation by Prof. Francis Ring of Glamorgan on the use of thermal imaging for fever screening and the process towards ISO standardisation of the methods for this. However, although more and more airports are using some form of IR imaging for fever screening few seem to be doing this properly when assessed against the ISO criteria.

Finally, the day was summed up by Prof. Ralph Jacobson. The event was deemed to be a success and we were particularly heartened by the student contribution to this meeting, both as presenters and attendees. We hope for similar success next year!

Original programme, with links to authors' presentations if available:

09:00-09:50 Tea/Coffee & Registration
09:50-10:00 Welcome & Introduction S. Triantaphillidou
10:00-10:40 Plenary talk:
Image Quality Measurements: Necessity, Numbers and '....nesses'
R. Jacobson
University of Westminster,
10:40-11:05 A review of ISO 20462: A 3-part international standard for the measurement of psychophysical image quality H. Muammar
11:05-11:30 Colour image quality G. Attridge
University of Westminster, UK
11:30-11:50 Coffee
11:50-12:15 Image classification with respect to image quality measurements H. Oh, et al,
University of Westminster, UK
12:15-12:35 Multidimensional image selection and classification based on feature extraction and visual scaling F. Mancusi, et al.
University of Westminster, UK
12:35-13:00 A colour naming investigation within different cultures D. Mylonas
London College of Communication, UK
13:00-13:50 Lunch
13:50-14:15 Role of imaging in a study to measure the perceived degree of naturalness of 'real' and 'synthetic' surfaces R. Montgomery, et al.
National Physical Laboratory, UK
14:15-14:40 The assessment of image usefulness in security recording systems: frame rate and compression A. Tsifouti et al.
14:40-15:05 Image quality evaluation, optimization and object recognition in the reproduction of medical radiographs H. Ebrahim,
University of Limpopo, SA
15:05-15:20 Coffee
15:20-15:45 A method to compare the accuracy of colour representation obtained with wide dynamic range pixels with different responses S. Collins,
University of Oxford, UK
15:45-16:10 Camera identification using statistical process control techniques for anomaly detection P. Bateman,
University of Surrey, UK
16:10-16:35 Fever detection by infrared imaging - Hot topic! F. Ring et al.,
University of Glamorgan, UK
16:35-16:45 Closing by the past president of the RPS R. Jacobson