To explain the general workflow of RFT we start with a well-defined, fully synthetic image (Fig. ). We simulated the image by plotting a sinusoidal waveform with a wavelength of 50 pixels and an orientation angle of 130° over an entire frame of 512 by 512 pixels. The intensity values range from 0 and 255 counts with a bit depth of 8 bits. To enable testing for structural anisotropy, we further replaced the central part of the image with a circular section of radius 150 pixels with the same wavelength of 50 pixels, but an orientation angle of 0° (or 180°). The entire image is then computationally partitioned into a number I = 256 of squared regions, labelled as i: an illustrative example of such regions is shown in Fig. (green box). For each region i, we chose a window size of 101 by 101 pixels. This value ensures that the size of the window is well above the corresponding feature size, namely the peak-to-peak distance of 50 pixels in our waveform, passing the Nyquist criterion frequency . The partitioning of the entire image is done using overlapping window regions, enabling us to detect angular features that would otherwise fall between neighbouring regions. The image is divided into sub-images, using the sliding windows, with 75% being the chosen overlapping fraction between adjacent windows.