A Data Hiding Method Using Mquant in MPEG Domain

Abstract

〈Summary〉 This paper proposes a novel data hiding method utilizing Mquant as the data carrier in MPEG domain. To the best of our knowledge, Mquant is never used as the data carrier for information hiding. Mquant is the principle part of rate controller in MPEG, and it is one level higher than the existing data carriers such as quantized DCT coefficients and motion vectors in the MPEG coding hierarchy. In our method, matrix encoding is utilized as the data representation scheme for reducing the number of modification whenever possible. A modification scheme is proposed to sub-optimally preserve the original distribution of Mquant during data embedding. Our data hiding method is applicable not only to MPEG1/2/4 encoded video but also to the encoding process of MPEG video from a sequence of raw pictures. Carrier capacity, histogram distance, image quality, and filesize change are considered to verify the basic performance of the proposed method using various videos encoded by MPEG1. Comparisons among the proposed and existing data carriers are carried out using the same evaluation criterion. The influence of video bitrate on the performance of our method is also investigated.