Methods and systems of estimating b-values. One system including an electronic processor configured to receive a set of medical images associated with a patient, where the set of medical images are diffusion-weighted images. The electronic processor is also configured to extract a set of patches from each medical image included in the set of medical images. The electronic processor is also configured to determine, via an estimation model trained using machine learning, a set of estimated b-values, where each estimated b-value is associated with a patch included in the set of patches. The electronic processor is also configured to determine a b-value for each of the medical images included in the set of medical images, where the b-value is based on the set of estimated b-values.