High capacity HEVC video information hiding method

The invention discloses a high capacity HEVC video information hiding method; wherein the method comprises following steps of hiding secret information and extracting the secrete information; according to the step of hiding secret information, firstly, 11 prediction mode subgroups are established; the prediction mode subgroup to which the optimum prediction mode of each 4x4 brightness block in each frame of I frames is determined; then secret information embedding operations are carried out according to extracted two-digit bit information and the prediction mode subgroup to which the optimum prediction mode of each 4x4 brightness block in each frame of I frames; according to the step of extracting the secrete information, firstly, the 11 prediction mode subgroups are established; the prediction mode subgroup to which the optimum prediction mode of each 4x4 coding block in the I frames is determined; and then secret information extraction operations are carried out according to the optimum prediction mode of each 4x4 coding block in the I frames and the prediction mode subgroup to which the optimum prediction mode belongs. The method has the advantage that the secret information embedding capacity can be effectively improved on the premise of ensuring the subjective and objective quality of a video.