the mobile network and fixed network is higher than the point of indifference, whatever that happens to be. The reduction of solid-state memory cost, the increase in solid-state memory density and a reduction in memory power drain have made it easier both technically and commercially to provide phones with enough memory to support the home-upload option. Imaging capabilities in mobile phones can, however, provide significantly more functionality than just taking pictures. For a start phones can potentially see in the dark better than we can and can see things in higher resolution and greater colour depth and in parts of the ultraviolet or infrared spectrum. Imaging functionality can include an ability to perform tasks that would be otherwise difficult, reading a bar code for example. The combination of imaging with pattern recognition and/or pattern matching combined with user context and location and positioning context potentially allows a mobile device to move from being a communications tool to a device that allows us to interact with the physical around us. Similarly combining imaging with other sensing capabilities may add value. Software has several functions in the image processing chain. Software can correct for distortions introduced by low-cost optical components and can be used to improve image quality including compensating for user limitations, shaky hands being an example. Software can then be used to sort images or search images or match images. Making Telecoms Work: From Technical Innovation to Commercial Success, First Edition. Geoff Varrall. © 2012 John Wiley & Sons, Ltd. Published 2012 by John Wiley & Sons, Ltd. Making Telecoms Work The imaging processing chain and the software used in the image processing chain therefore merits attention both in terms of what it can do today but also what it may be able to do in the future. 8.2 The Image Processing Chain When considering the imaging processing chain, it is logical to start with the image. Our eyes see the world in terms of brightness (luminan