Which is the fastest method to extract a rough orientation statistics from images. I think the most precise way is the scanning with local Gabor filters, but its very time consuming. Is it possible to use some kind of global transformations or filters? Fourier transformation can help in this case? If it helps, I can fix the wavelength.
There is Hough transform. conceptually simple but computationally still demanding. In engineering it is fairly a standard tool to locate the objects.