During the process, notice two points, which improve the adaptability of HS based RDH and affect its performance.(1) Peak bin P1 is not obligatory to be highest frequency bin, but the appropriate one with enough frequency to hide given secret message.(2) When relative large payload is required, rather than using just one pair of peak and zero bins (P1, Z1), some other strategies, i.e., ’multiple embedding’ on Level 2 or ’multilevel embedding’ on Level 3, might be employed, which could involve several pairs of peak and zero bins from the histogram and then perform multi-layer embedding.