No abstract

Digital watermarking is a promising and efficient methodology for protecting the copyright of the transmitted multimedia data. Three-dimensional videos (3DVs) are transmitted and stored in the form of compressed information.Thus, there is a great need for compressed 3DV watermarking. This paper presents 2 proposed hybrid watermarking schemes for securing the 3DV transmission. The first watermarking scheme is the homomorphic transform-based singular value decomposition in discrete wavelet transform domain. The second scheme is the 3-level discrete stationary wavelet transform in discrete cosine transform domain. The objective of the 2 proposed hybrid watermarking schemes is to increase the immunity of the watermarked 3DV to attacks and achieve adequate perceptual quality. The performances of the 2 proposed hybrid watermarking schemes are compared with those of the state-of-the-art watermarking schemes. The comparisons depend on both of the subjective visual results and the objective results; the peak signal-to-noise ratios of the watermarked frames and the normalized correlation of the extracted watermark frames. Extensive simulation results on standard 3DV sequences have been conducted in the presence of attacks. The obtained results confirm that the 2 suggested hybrid watermarking schemes are robust in the presence of attacks. They achieve not only very good perceptual quality with appreciated peak signal-to-noise ratio values but also high correlation coefficient values in the presence of attacks. beneficial to ensure copyright. A digital watermark can be embedded either in a compressed video or uncompressed video. 2 Video information are always transported and stored in the form of compressed data. The uncompressed video watermarking schemes can also be used for the compressed-video bit streams; however, they require complete video re-encoding and decoding for the watermark insertion or extraction. In different cases, the complete video stream decoding process is not recommended. So, the compressed video watermarking has recently acquired more attentiveness. Furthermore, the watermark insertion and extraction in compressed data has less computations, because the complete reencoding and decoding of the transmitted stream is not required for embedding and extracting the watermark bits.Recently, several video encoding standards have emerged. The objective of an encoding standard is to achieve high data compression, while maintaining an acceptable quality. The 3D multiview video coding (3D-MVC) is an efficient one of the recent encoding standards used in different applications. The 3D-MVC has received a broad attentiveness, and it is expected to rapidly take place of traditional 2D video coding in numerous applications. 3 In the 3D-MVC system, the original 3D video (3DV) consisting of multiple video streams is taken for the same object by various cameras. Thus, to transport the 3DV over limited resources networks, a highly efficient compression standard must be applied, whilst preserving a high reception quality. ...

No abstract

Summary In the Three‐Dimensional Multi‐View Video (3D MVV) coding prediction structure, the coded bit‐streams may be dropped down due to error transmissions. So, it is compulsory to recover the corrupted Macro‐Blocks (MBs) at the decoder utilizing efficient Error Concealment (EC) post‐processing techniques. The EC methods exploit the temporal, inter‐view, and spatial matching among 3D MVV views and frames without any alterations in the encoder software or hardware or in the transmission rate. They retrieve the Disparity Vectors (DVs) and Motion Vectors (MVs) of the erroneous MBs. To enhance the received 3D MVV quality, we suggest several optimized schemes to reconstruct the lost and erroneous MBs of inter‐encoded and intra‐encoded frames. A hybrid method combining the Circular Scan Order Interpolation Algorithm (CSOIA) and Partitioning Motion Compensation Algorithm (PMCA) is proposed for intra‐frame EC. For inter‐corrupted MBs, a hybrid method comprising Directional Textural Motion Coherence Algorithm (DTMCA) and Directional Interpolation Error Concealment Algorithm (DIECA) is suggested. Experimental outcomes on several 3D MVV frames demonstrate that the suggested EC algorithms have more robustness to both heavily random and slice losses. They objectively and subjectively work better than the state‐of‐the‐art EC techniques. The proposed work achieves high 3D MVV quality with an improved average Peak Signal‐to‐Noise Ratio (PSNR) gain up to 2.45 to 4.55 dB compared with traditional EC algorithms at Packet Loss Rates (PLRs) of 40%.

No abstract