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With the increasing number of video applications, it is essential to resolve issues such as ineffective search of video content, tampered/forged video content, packet loss, to name a few. Data embedding is typically utilized as one of the solutions to address the aforementioned issues. One of the important requirements of data embedding is to maximize embedding capacity with minimal bit rate overhead while ensuring imperceptibility of the inserted data. However, embedding capacity varies depending on the video content and increasing the embedding capacity usually leads to video quality degradation. In this work, a threshold-controlled block splitting technique is proposed for embedding data into SHVC video. Specifically, the embedding capacity can be increased by coding the host video by using more small blocks, which can be achieved by tuning a threshold-controlled parameter in the rate distortion optimization process. Subsequently, the predictive syntax elements in both intra and inter-coded blocks are jointly utilized to embed data, which ensures that data can be embedded regardless of the prediction mode used in coding a block. Results suggest that the proposed method can achieve a trade-off between the increase in embedding capacity and bit rate overhead while maintaining video quality. In the best case scenario, the sequence PartyScene can embed 516.9 kbps with an average bit rate overhead of + 7.0 % for the Low Delay P configuration, while the same video can embed 1578.6 kbps with an average bit rate overhead of + 2.9 % for the All Intra configuration. [ABSTRACT FROM AUTHOR]

With the rapid advancement in digital technologies, video rises to become one of the most effective communication tools that continues to gain popularity and importance. As a result, various proposals are put forward to manage videos, and one of them is data embedding. Essentially, data embedding inserts data into the video to serve a specific purpose, including proof of ownership via watermark, covert communication in steganography, and authentication via fragile watermark. However, most conventional methods embed data by using only one type of syntax element defined in the video coding standard, which may suffer from large bit rate overhead, quality degradation, or low payload. Therefore, this work aims to explore the combined use of multiple prediction syntax elements in SHVC for the purpose of data embedding. Specifically, the intra prediction mode, motion vector predictor, motion vector difference, merge mode and coding block structure are collectively manipulated to embed data. The experimental results demonstrate that, in comparison to the conventional single-venue data embedding methods, the combined use of prediction syntax elements can achieve higher payload while preserving the perceptual quality with minimal bit rate variation. In the best case scenario, a total of 556.1 kbps is embedded into the video sequence PartyScene with a drop of 0.15 dB in PSNR while experiencing a bit rate overhead of 7.4% when all prediction syntax elements are utilized altogether. A recommendation is then put forward to choose specific types of syntax element for data embedding based on the characteristics of the video. [ABSTRACT FROM AUTHOR]

A joint encryption and authentication scheme for HEVC compressed video is proposed in this work. It produces a HEVC format compliant video stream that permits the authentication process to be carried out irregardless of the video being in the encrypted or plaintext (i.e., decrypted) form. To achieve this separable property, one set of syntax elements within the HEVC standard is utilized to achieve authentication, while another set is exploited for encryption. Specifically, for authentication, information such as coding unit size in each video slice is utilized to generate the authentication code, which is then embedded into each video slice to detect the tampered regions. A two-level authentication method is implemented to facilitate the legitimacy verification process. On the other hand, for video encryption, syntax elements in the HEVC standard including Sign Bins, Transform Skip Bins and Suffix Bins are randomized to perceptually distort the video. Experiment results show that by using the proposed encryption modules, the perceptual quality of the plaintext video can be distorted, and the distorted video can be restored to the original HEVC compressed video. Furthermore, the proposed joint scheme is verified to be viable in detecting and localizing the tampered regions. Finally, a pragmatic comparison among the proposed and conventional joint schemes is performed. [ABSTRACT FROM AUTHOR]

In this paper, we propose a novel sketch attack for H.264 advanced video coding (H.264/AVC) format-compliant encrypted video. We briefly describe the notion of sketch attack, review the conventional sketch attacks designed for discrete cosine transform (DCT)-based compressed image, and identify their shortcomings when applied to attack compressed video. Specifically, the conventional DCT-based sketch attacks are incapable in sketching outlines for inter frame, which is deployed to significantly reduce temporal redundancy in video compression. To sketch directly from inter frame, we put forward a sketch attack by considering the partially decoded information of the H.264/AVC compressed video, namely, the number of bits spent on coding a macroblock. To evaluate the sketch image, we consider the Canny edge map as the ideal outline image. Experiments are conducted to verify the performance of the proposed sketch attack using ICADR2013, High Efficiency Video Coding dash, and Xiph video data sets. Results suggest that the proposed sketch attack can generate the outline image of the original frame for not only intra frame but also inter frame. [ABSTRACT FROM AUTHOR]

A multi-layer authentication scheme for HEVC compressed video is proposed. The combination of CU sizes, which is unique to HEVC and sensitive to video manipulation, is considered along with other elements in the HEVC coding standard to generate the authentication tag. Temporal dependency was enforced, where the authentication tag generated in one slice is embedded into its subsequent slice. By design, the authentication tag is repeatedly but selectively embedded into various elements in a HEVC video, including nonzero DCT coefficients, QP parameter values, and prediction modes, depending on the bit segment in the generated tag. Our scheme offers three layers of authentication to detect and localize the tampered regions in a HEVC video, as well as verifying the source/sender of the video using a shared secret key. Video sequences from various classes (resolutions) are considered to verify the performance of the proposed multi-layer authentication scheme. Results show that, at the expense of slight degradation in perceptual quality, the proposed scheme is robust against several common attacks. A functional comparison is performed between the proposed multi-layer authentication scheme and the conventional schemes. [ABSTRACT FROM AUTHOR]

The progression toward spatially scalable video coding (SVC) solutions for ubiquitous endpoint systems introduces challenges to sustain real-time frame rates in downsampling high-resolution videos into multiple layers. In addressing these challenges, we put forward a hardware accelerated downsampling algorithm on a parallel computing platform. First, we investigate the principal architecture of a serial downsampling algorithm in the Joint-Scalable-Video-Model reference software to identify the performance limitations for spatially SVC. Then, a parallel multicore-based downsampling algorithm is studied as a benchmark. Experimental results for this algorithm using an 8-core processor exhibit performance speedup of 5.25× against the serial algorithm in downsampling a quantum extended graphics array at 1536p video resolution into three lower resolution layers (i.e., Full-HD at 1080p, HD at 720p, and Quarter-HD at 540p). However, the achieved speedup here does not translate into the minimum required frame rate of 15 frames per second (fps) for real-time video processing. To improve the speedup, a many-core based downsampling algorithm using the compute unified device architecture parallel computing platform is proposed. The proposed algorithm increases the performance speedup to 26.14× against the serial algorithm. Crucially, the proposed algorithm exceeds the target frame rate of 15 fps, which in turn is advantageous to the overall performance of the video encoding process. [ABSTRACT FROM AUTHOR]

Information hiding refers to the process of inserting information into a host to serve specific purpose(s). In this paper, information hiding methods in the H.264/AVC compressed video domain are surveyed. First, the general framework of information hiding is conceptualized by relating the state of an entity to a meaning (i.e., sequences of bits). This concept is illustrated by using various data representation schemes such as bit plane replacement, spread spectrum, histogram manipulation, divisibility, mapping rules, and matrix encoding. Venues at which information hiding takes place are then identified, including prediction process, transformation, quantization, and entropy coding. Related information hiding methods at each venue are briefly reviewed, along with the presentation of the targeted applications, appropriate diagrams, and references. A timeline diagram is constructed to chronologically summarize the invention of information hiding methods in the compressed still image and video domains since 1992. A comparison among the considered information hiding methods is also conducted in terms of venue, payload, bitstream size overhead, video quality, computational complexity, and video criteria. Further perspectives and recommendations are presented to provide a better understanding of the current trend of information hiding and to identify new opportunities for information hiding in compressed video. [ABSTRACT FROM PUBLISHER]

Recent advancements in high resolution scalable video coding have significantly increased the computational complexities of watermarking solutions for real-time video encoding systems. This paper proposes a human visual system based watermarking algorithm for spatial scalable coding based on the H.264/SVC standard. The proposed algorithm extracts textural feature from a set of 7 high energy quantized coefficients in 4×4 luma INTRA-predicted blocks of all slices and embeds watermark into the highly textured block which has at least one non-zero coefficient in 6 selected locations. The same embedding process is performed for all layers of the video to improve robustness against common video processing attacks. Experiments were conducted by embedding up to 8192 watermark bits into a four-layer spatial scalable coded video. Results suggest that the proposed scheme produces watermarked video with an average visual quality degradation of ∼0.36 dB at the expense of 2.18% bitrate overhead. In addition, the proposed watermarking scheme achieves an average detection rate of 0.98, 0.97 and 0.71 against re-encoding, recompression and Gaussian filtering attacks, respectively, using the base layer, and above 0.97, 0.94 and 0.66, respectively when using any of the enhancement layer. [ABSTRACT FROM AUTHOR]