Abstract
This paper proposes a decreasing technique of increase rate of data size in the partial scrambling technique. In the proposed technique, quantized DCT coefficients in I-frames are shuffled or changed by a target image quality for PSNR. The amount of change to scramble is corrected in order to be independent on the kinds of videos, and to shuffle or to change the quantized DCT coefficients is selected to decrease the increase rate of data size. In addition, the result of increase rate of data size and subjective evaluation experiment show the effectiveness of the proposed technique.