Description
PART A
Develop a computer program that creates a “tilt-shift effect” on images. This effect is usually created by special lenses
that are able to capture a shallow depth of field. It can also be created by post-processing. As illustrated in Fig 1, the result is an interesting miniaturization effect. Notice that parts of these images are heavily blurred leaving only a small part
in focus. This effect can easily be created by selectively applying a Gaussian filter on images.
Fig 1. Tilt-shift effect examples
For Part A, apply a 5×5 Gaussian filter (implemented as cascaded 5×1 and 1×5 filters) iteratively. At first iteration,
Gaussian filter is applied to the image except for the band (i.e. K d) defined by a row number K (e.g. 200) and a distance d (e.g. 20). At the next iteration, the unaltered band is extended to K 2d. Iterations end when the band contains
the whole image.
Your program should accept 3 arguments (K,d and file name) in the command line. E.g.:
> ./tilt_shiftA 200 20 [.pgm file]
PART B
Modify your program developed for part A. This time, unaltered regions are circular regions defined by a center and a radius that is extended by “d” at each iteration.
Your program should accept 4 arguments (Center_i, Center_j, d and file name) in the command line. E.g.:
> ./tilt_shiftB 200 150 20 [.pgm file]
Fig 2. (a) Illustration for part A. (b) Illustration for part B.
Sample images that can be used for this homework will be available in file hw4images.zip. Your code (with inline comments and instructions on how to compile) should be submitted via MS Teams, at or before the due date/time. .
