Hello Debabrata, thank you for your interest into Boost.GIL ! While I think it would be great for Boost.GIL users to be able to perform Fourier transforms on their images, I'm not convinced the best way to support that would be by adding our own FFT implementations to Boost.GIL. Given the amount of work (and expertise !) that goes into existing third-party FFT libraries (such as FFTW: http://fftw.org/), I think it's far more useful to make sure Boost.GIL can readily use (or be used with) such libraries. As far as Boost.GIL competency tests are concerned, I would much rather see you demonstrate your ability to write modern C++(11 and beyond) code, and use the existing Boost.GIL APIs, rather than focus on algorithms, though of course knowledge of algorithms and the ability to implement them is an important skill, too. Finally, don't under-estimate the work needed to write (reasonably well-performing) FFTs. It seems to me that this would be beyond the scope of any test assignment (even a full GSoC project, I would argue). Keep up your enthusiasm ! Good luck, Stefan -- ...ich hab' noch einen Koffer in Berlin...