“…Apart from the complementary (hard-)biometric traits, soft-biometric traits such as age [223], height [224], [225], weight [226], gender [227], and particular body marks including tattoos [228] can also be included to boost overall performance. The combination of other softand hard-biometric traits with gait has mostly been done in the literature based on non-deep methods [229], [230], [231], [232], [233], [234], while multi-modal deep learning methods [235], [236], notably based on fusion [237], joint learning [208], and attention [238] networks, can also be adopted. Hence, we anticipate that research on deep multi-biometric recognition systems that include gait, gain popularity in the coming years.…”