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Significant research has been carried out in terms of development of new bidirectional reflectance distribution function (BRDF) instruments; however, there is still little research available regarding spectral BRDF measurements of human skin. This study aims to investigate the variation in human skin reflectance using a new fibre optic-based spectral-BRDF measurement device.

Design of this system mainly involves use of multiple fibre optics to illuminate and detect light reflected from a sample, whereas a hemispherical dome was 3D printed to mount the fibres at various slant/tilt angles. To investigate the spectral differences in BRDF of human skin, 3 narrowband filters in the visible spectrum were used, whereas measurements were taken from the back of the hand for Caucasian and Asian skin types.

The experiments demonstrate that the BRDF of human skin varies with wavelengths in the visible spectrum and it is also different for Caucasian and Asian skin types. Both skin types exhibit off-specular reflection with increase in angle of incidence and show less variation with respect to viewing angles when the angle of incidence is normal to the surface.

A database of spectral BRDF measurements of human skin will help not only in creating realistic skin renderings but also in development of novel skin reflectance models for biomedical and machine vision applications. The measurements would also provide means to validate the predictions from existing light transport/spectral simulation models for human skin and will ultimately help in the accurate diagnosis and simulation of various skin disorders.

The proposed system provides fast scatter measurements by utilising multiple fibres to detect light simultaneously at different angles while also allowing easy switching between incident light directions. Due to its flexible design and contact-based measurements, the device is independent of errors due to sample movements and does not require any image registration. Also, measurements taken from the device show that the BRDF of skin varies significantly in the visible spectrum and it is different for Caucasian and Asian skin types.

This paper aims to introduce an unsupervised modular approach for eye centre localisation in images and videos following a coarse-to-fine, global-to-regional scheme. The design of the algorithm aims at excellent accuracy, robustness and real-time performance for use in real-world applications.

A modular approach has been designed that makes use of isophote and gradient features to estimate eye centre locations. This approach embraces two main modalities that progressively reduce global facial features to local levels for more precise inspections. A novel selective oriented gradient (SOG) filter has been specifically designed to remove strong gradients from eyebrows, eye corners and self-shadows, which sabotage most eye centre localisation methods. The proposed algorithm, tested on the BioID database, has shown superior accuracy.

The eye centre localisation algorithm has been compared with 11 other methods on the BioID database and six other methods on the GI4E database. The proposed algorithm has outperformed all the other algorithms in comparison in terms of localisation accuracy while exhibiting excellent real-time performance. This method is also inherently robust against head poses, partial eye occlusions and shadows.

The eye centre localisation method uses two mutually complementary modalities as a novel, fast, accurate and robust approach. In addition, other than assisting eye centre localisation, the SOG filter is able to resolve general tasks regarding the detection of curved shapes. From an applied point of view, the proposed method has great potentials in benefiting a wide range of real-world human-computer interaction (HCI) applications.

This paper aims to review state of the art of techniques for dimensioning chronic wounds, and validate the possibilities of employing a new proposed optical imaging approach for general task of wound assessment.

Current techniques used for quantifying wound surface are reviewed and evaluated from various perspectives to exam their usability in wound care clinical settings. A photometric stereo (PS) approach will be identified and verified to work as an alternative solution to better satisfy practical requirements on quantifying the dimension of real and mocked wounds.

Both contact and contactless approaches provide some useful functions for wound management; however, new imaging modalities are still required for achieving good portability, affordability and applicability in assisting decision-making in clinical settings. The PS approach can work as a potential solution to provide these functionalities as well as dense geometrical and color texture information of measured areas. The experiments demonstrate that the new approach is able to conveniently produce comparable results to those from latest stereo vision-based techniques.

This work proposed and initially verified the potential of PS technique for the task of wound measurement. Substantial improvements on the prototype and more clinical trials are still required to validate the new technique before it is accepted as a tool for practical wound measurement.

This new PS approach has good potential to reliably measure the dimension of wounds as well as recover their color texture which could contain additional valuable information for predicting a healing procedure for those wound occurring deeper underneath the skin surface.

MELVYN BARNES, Borough Librarian & Arts Officer of the Royal Borough of Kensington & Chelsea (London), was asked to prepare a report for his libraries committee on the possibility of selling withdrawn library books to the public—that rumbling bandwagon which inevitably looks attractive to local authorities in hard times.

A HICCUP in the Library Association's plans for the new Record may be presumed from the appearance in late March of a ‘re‐advertisement’ for the post of Editor, coupled with the advice that former applicants need not re‐apply (so much for my hopes of a sheltered haven when the economic deluge arrives!).

PROMPTLY UPON the ending of the seemingly interminable Christmas/New Year holiday—I just had to go back to work between the two, because another plate of cold‐turkey‐plus‐cold‐Xmas‐pud would have driven me insane—there landed upon my desk the first issue of the LAR vacancies supplement, a sheet of job advertisements which is to be issued fortnightly while publication of the Times literary supplement Is suspended, and may even be continued thereafter on a permanent basis if demand warrants.