This is a diffusion-weighted MRI processing Matlab toolbox (including binaries), which can be used to:• Compute the Q-Ball Imaging Orientation Distribution Function in Constant Solid Angle (CSA-ODF) (Aganj et al, MRM 2010).• Perform Hough-transform tractography (Aganj et al, MedIA 2011).• Visualize ODFs and tracts, and export them for further analysis.• Verify the correctness of the diffusion gradient table (Aganj, Sci Rep 2018).• Compute and interactively visualize the connectivity matrix.• Augment the connectivity matrix with indirect connections (Aganj et al, ISMRM 2014).• Estimate the spatial gradient of the image from the diffusion MRI signal (Aganj et al, ISMRM 2023, bioRxiv 2025).For short tutorials, see EXAMPLE.m and EXAMPLE_CLI.m. If available, GPUs can be used for speed-up.