Last Friday the Studio welcomed Professor David Bull, Director of the Bristol Vision Institute (BVI), who came in to explain the ethos behind his virtual organization and to show us some examples of the types of work that he and his colleagues are engaged in.

The BVI was set up in 2007 with the aim of answering big questions in the field of vision research that reach across traditional academic divides. It consists of 14 departments, made up of around 100 people whose work spans a diverse number of disciplines and a broad scope of interests that extend beyond the creative industries through to biological sciences and mathematics.

David discussed the main challenges that the BVI was formed to tackle: questions of what vision is for and why it should be studied, how to know what to look for next in the field and how such research can be applied. He explained that the Institute works to explore these topics by seeking out new optical mechanisms that can be adapted to allow for the development of better formats and modalities within visual systems and that can be utilized in the optimization of sight experiences.

As an example of the way a project might be approached by the BVI, David told us about the mantis shrimp, a creature whose eyes are receptive to 12 colour channels and polarization of light and whose attack is the fastest and most accurate in the animal kingdom. By studying the visual capabilities of such animals, researchers can make use of reverse engineering to open up new avenues of technological development, recreating the effects of such perceptive faculties and thus replicating the benefits for human use.

The facilities at the BVI studio include not only a wide variety of cameras and displays, but also a locomotion and vision lab, with eye trackers, treadmills and gait analysis devices that are used to gain an understanding of how humans interact with their environments. This research feeds into the Institute’s work on robot vision, looking into how the use of optical systems can enhance the way bipedal robots navigate terrain.

The BVI are also interested in studying the relevance of visual systems such as colours and patterns in nature, looking into the ways that camouflage and disruptive patterns are perceived and used as a survival tool by different animals. They have carried out research on the significance of spots and stripes, concluding that the patterning on animals that travel in groups (i.e. Zebras) has evolved to create the effect of a much larger, less vulnerable prey to potential predators. Such studies have military applications, as disruptive camouflage was used to adorn ships in both World Wars and studies have shown that the human capacity for gauging speed of movement is effected by patterns.

Research into animal biometrics has yielded the discovery of reaction-diffusion systems; equations that explain how small variations in genetic systems can produce a range of patterns in animal coats and provide an insight into how distinct patterns are generated for each individual member of a species. Following on from this research, David showed us examples of computer programs that have been developed to provide automatic recognition of individual animals by differentiating between them according to these systematically generated patterns (such as the spots on the chests of penguins or the wrinkles on the faces of gorillas). This type of biometric identification program can be used to produce metadata for image retrieval, helping to extract data or footage from film archives.

David then moved on to talk about foveated imaging, a digital processing technique that involves varying the resolution of an image in accordance with focal points dictated by an understanding of eye movement and analysis of human data-retrieval behaviours. Useful in contexts such as advertising or the assessing of website usability, foveated imaging draws upon research into the way that deaf signers interact with each other (focusing primarily on the nose / mouth) and uses the principles found in that context to limit the resolution of peripheral visual content outside of the designated communicatively functional areas of images and video, allowing for the reduction of file sizes.

Similar studies of the eye activity of people viewing artworks that feature gilding have provided an insight into how artists used gold leaf to produce specific effects and guide the viewer’s perceptions before electrical lighting, an understanding that can be transferred to other visual art forms to aid in the production of strong compositions.

David explained that humans find it difficult to perceive differences from a spatial perspective, especially small differences in arrangements of shapes. Exploiting this limitation, texture synthesis compression techniques such as graph cutting or steerable pyramids have been developed to artificially fill in sections of images with appropriate textures, again helping to minimise file sizes. David has helped to develop a process called ‘regional classification’, which analyses moving images in order to designate areas of footage that are suitable for being replaced by computer generated textures.

The BVI also carry out research into understanding the immersive properties of various formats, looking at how factors such as screen size, shot length and the use of high dynamic range imaging draw people into media, enhancing the presence and effect of films.

In closing, David showed us an example of how the Institute’s work has also been applied in an artistic project, capturing a three-dimensional image of a person’s breath and then rendering a sculpture from the captured form. This completed his overview of the BVI’s work, illustrating the huge scope of their studies and the wide variety of outcomes it produces.

For more information about the Bristol Vision Institute, visit: http://www.bristol.ac.uk/vision-institute/

Lunchtime Talks are an ongoing series of presentations and discussions by Studio residents and associates. They take place at 13:00 on Fridays and are free and open to everybody who’s interested in what we do. For the full programme of talks, please visit: http://www.pmstudio.co.uk/events