A DCT/DST-based error propagation-free data hiding algorithm for HEVC intra-coded frames q Po-Chun Chang a , Kuo-Liang Chung a , Jiann-Jone Chen b , Chien-Hsiung Lin a,⇑ , Tseng-Jung Lin a a Department of Computer Science and Information Engineering, National Taiwan University of Science and Technology, No. 43, Section 4, Keelung Road, Taipei 10672, Taiwan, ROC b Department of Electrical Engineering, National Taiwan University of Science and Technology, No. 43, Section 4, Keelung Road, Taipei 10672, Taiwan, ROC article info Article history: Received 26 June 2013 Accepted 24 October 2013 Available online 5 November 2013 Keywords: Data hiding DCT/DST H.264/AVC HEVC Intra-coded frames Intra-frame error propagation abstract Currently, two error propagation-free discrete cosine transform (DCT)-based data hiding algorithms, one by Ma et al. and the other by Lin et al., were presented for H.264/AVC intra-coded frames. However, the state-of-the-art video codec, high efficiency video coding (HEVC), adopts both integer DCT and discrete sine transform (DST) such that the previous DCT-based algorithms cannot fully utilize available capacity for data hiding in HEVC. This paper presents the first DCT/DST-based data hiding algorithm for HEVC intra-coded frames where the block DCT and DST coefficient characteristics are investigated to locate the transformed coefficients that can be perturbed without propagating errors to neighboring blocks. Experimental results confirm the merits of the proposed algorithm in providing the intra-frame error propagation-free advantage, the quality improvement for marked images, the compression power inher- ited from HEVC, and the superiority of embedding capacity for low bitrate coding when compared with the previous two algorithms for H.264/AVC. Ó 2013 Elsevier Inc. All rights reserved. 1. Introduction With the advance of digital multimedia communication tech- niques, data hiding becomes important in the authentication, iden- tification, annotation, and copyright protection of digital media items [18,3,10,15], among which digital video is most widely used. However, due to the massive information amount of digital video signals, it needs highly efficient video coding to make video com- munication feasible. Recently, several transform domain based data hiding algorithms [16,21,14,22,5,8,6,17] have been developed in H.264/AVC [4], where the quantized discrete cosine transform coefficients (QDCTs) of the 4  4 luma blocks in intra-coded frames (IFs) are perturbed so as to carry the hidden data. Unfortunately, these algorithms have the intra-frame error propagation problem due to the improper perturbation strategies for the QDCTs, leading to severe quality degradation for the reconstructed video signals. To solve this problem, Ma et al. [11] proposed an effective per- turbation strategy for the QDCTs of the 4  4 luma blocks based on both the directions of intra prediction modes and the deviation in the pixel values resulted from changing the QDCTs values. Lin et al. [9] proposed to increase the embedding capacity for the 4  4 luma blocks achieved by Ma et al. and to additionally utilize the other 4  4 luma blocks for embedding one bit into each of them. Although the intra-frame error propagation has been tackled in the algorithms [11,9], the inter-frame error propagation is another challenging problem for these transform domain based data hiding algorithms [13,23]. As the application demands higher video signal resolution, the H.264/AVC standard can no longer achieve satisfied compression performance. A state-of-the-art video coding standard, high effi- ciency video coding (HEVC) [2,19], is developed to improve the compression efficiency for high resolution video signals. When considering data hiding in HEVC video sequences, one intuitive way is to adapt the previous data hiding algorithms used for H.264/AVC to the HEVC standard. However, since the HEVC 4  4 block does not utilize integer DCT for transform coding, the trans- form domain data hiding algorithms developed based on 4  4 DCT blocks of H.264/AVC cannot be applied to HEVC. Hence, developing a data hiding algorithm that can support the transform coding adopted by HEVC while eliminating the intra-frame error propaga- tion and alleviating the inter-frame error propagation is required, which motivates this research. In this paper, we propose an error propagation-free data hiding algorithm for HEVC IFs. The main idea of the proposed algorithm is to categorize blocks so as to impose specific quantized coefficient perturbation patterns for intra-frame error propagation-free data hiding under the HEVC framework. For HEVC IFs, we propose a DCT and discrete sine transform (DST)-based coefficient 1047-3203/$ - see front matter Ó 2013 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.jvcir.2013.10.007 q The work of K.L. Chung and C.H. Lin was supported by the National Science Council of ROC under the contracts NSC99-2221-E-011-078-MY3, NSC101-2221-E- 011-139-MY3, and NSC102-2221-E-011-055-MY3. The work of J.J. Chen was supported by the National Science Council of ROC under the contract NSC101- 2221-E-011-137. ⇑ Corresponding author. E-mail address: d9409301@mail.ntust.edu.tw (C.-H. Lin). J. Vis. Commun. Image R. 25 (2014) 239–253 Contents lists available at ScienceDirect J. Vis. Commun. Image R. journal homepage: www.elsevier.com/locate/jvci