Defocus simulation

This function simulates the shift-variant defocus blur due to the limited depth of field of a digital camera. It works my mapping a source irrandiance (image) to a given depthmap and generates an image sequence at different focus positions using a gaussian PSF derived from geometrical optics. For a detailed description of its working principles, refer to appendix B in [1]. This defocus model has been used in [2] and [3]. For a demo, simply run 'blurdemo' at the matlab prompt.
References:
[1] S. Pertuz, Modeling and applications of the focus cue in conventional digital cameras. PhD thesis. Universitat Rovira i Virgili, 2013.
[2] S. Pertuz, D. Puig, M. A. Garcia, Analysis of focus measure operators for shape-from-focus, Pattern Recognition, 46(5): 1415-1432, 2013.
[3] S. Pertuz, D. Puig, M. A. Garcia, Reliability measure for shape-from-focus, Image and Vision Computing, Volume 31(10):725–734, 2013