Keith Godfrey

Applying neural networks to colour image data compression

A self-organizing neural network is used to achieve color image segmentation and image data compression, with an adaptive codebook for faster training. Neural network architectures are well-suited to high speed processing because they are massively parallel. By adding an external threshold decision, a compression network can build its codebook adaptively and therefore speed the compression process. A 24-bit color image is compressed to 6.39 bit with virtually no visual degradation.<<ETX>>

Pitching Research Evolution: An Illustrative Example on the Topic of 'Innovation and Financial Dependence'

As a visiting exchange student to the University of Queensland from China, Jie Teng, approached the 1st author inquiring about opportunities for research projects. Recognizing that the student had only limited exposure to research and an unknown appreciation of what it entails, the mentor devised a program of incremental “discovery” and learning, based on Faff’s (2015, 2016) “pitching research” template tool. Under close guidance, Jie was asked to choose a recent academic paper of interest to him and then to reverse engineer a “pitch” for that chosen paper. The target for this exercise was Acharya and Xu (2013, NBER) (now a forthcoming paper in Journal of Financial Economics, Acharya and Xu 2016): a paper examining the topic of “Innovation and Financial Dependence”. The pitching process was completed, in 10 small stages, over a period of about 5 weeks. The current paper provides a narrative of this research journey aimed at helping other research mentors facing similar situations.

Non-linear quantisation effects in digital colour systems

This paper shows that quantisation of colour pixels, essential to digital imagery, causes non-linear correlation in the permitted values of chromaticity coordinates in linear-intensity CIE colour spaces. It follows that colour video and image coding schemes based on these colour spaces will suffer an inherent preference for certain chromaticities.