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In multiview video coding (MVC), disparity-compensated prediction (DCP) exploits the correlation among different views. A common approach is to use block-based motion-compensated prediction (MCP) tools to predict the disparity effect among different views. However, some regions in different views may have various deformations due to nonconstant depth. Thus, performance of DCP is not satisfactory with the simple translational model assumed in conventional block-based MCP tools. Previous attempts to achieve better disparity prediction were usually too complex for practical use. In this paper, horizontal scaling and shearing (HSS) effects are investigated to increase interview prediction accuracy for stereo video. HSS deformations are common among images of horizontally aligned views, due to horizontal and vertical flat surfaces that are not parallel with projection image planes. To achieve HSS-based DCP with minimal complexity, an efficient subsampled block-matching technique is adopted and integrated into MVC extension of H.264/AVC in stereo profile. Affine parameters estimation and additional frame buffers are not required and the overall increase of computational complexity and memory requirements are moderate. Experimental results show that the new technique can achieve up to 5.25% bitrate reduction in interview prediction using JM17.0 reference software implementation. [ABSTRACT FROM PUBLISHER]

Edge is an important feature in video classification which finds applications in video representation and coding. In H.264/AVC, intra-prediction mode decision (a computationally intensive process) is based on the orientation of the edges in the macroblock. In this paper, we first investigate the difference properties derived from three coefficients in the non-normalized Haar transform (NHT) domain and present a fast and efficient method to classify block edge using these properties. The proposed method significantly reduces the number of computational operations in the edge models determination with no multiplications and less addition operations. The use of edge classification for fast intra-prediction mode decision in H.264/AVC video coding is then presented. The experimental results show the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Frame rate up-conversion is a postprocessing tool to convert the frame rate from a lower number to a higher one. It is a useful technique for a lot of practical applications, such as display format conversion, low bit rate video coding and slow motion playback. Unlike traditional approaches, such as frame repetition or linear frame interpolation, motion-compensated frame interpolation (MCFI) technique is more efficient since it takes block motion into account. In this paper, by considering the deficiencies of previous works, new criteria and coding schemes for improving motion derivation and interpolation processes are proposed. Next, for video coding applications, adaptive frame skip is executed at the encoder side to maximize the power of MCFI so that the quality of interpolated frames is guaranteed. Experimental results show that our proposal effectively enhances the overall quality of the frame rate up-converted video sequence, both subjectively and objectively. [ABSTRACT FROM AUTHOR]

Characterized by their distinctive motion patterns, temporal textures are natural phenomenon exhibiting spatio-temporal regularity with indeterminate spatial and temporal extent. This paper presents a real-time motion-based temporal texture characterization technique for the first time using block-based motion measures with very high classification accuracy against the popular opinion that such an accurate characterization is only possible using pixel-based measures. Finding an optimal weight ratio between space and time domain features where the accuracy of this block-based technique peaks has been the essence of this success. Computational complexity analyses and classification results clearly demonstrate the capability of the proposed technique in producing comprehensive classification results comparable to the best pixel-based technique with overwhelming reduction in computational complexity. [ABSTRACT FROM AUTHOR]

This paper describes a new technique for reducing the blockiness that results from using the reduced-resolution update (RRU) video coding tool. In RRU coding, full resolution prediction error residuals are downsampled and coded at a reduced spatial resolution. In previous versions of RRU, such as that defined in Annex Q of the H.263 standard, each block of prediction errors is processed without using samples from any neighboring blocks. This can lead to severe blockiness in the decoded picture. To reduce this blockiness 11.263 Annex Q RRU increases the deblocking filter strength to the maximum value. In the new technique presented here, referred to as RRU+, the downsampling and interpolation filters use residuals from neighboring blocks to prevent the blockiness that results from RRU. Experimental results comparing RRU+, RRU with normal deblocking filter strength (referred to simply as RRU in this paper), and RRU with maximum deblocking filter strength are presented. These results show that, while RRU+ and RRU with maximum deblocking strength both eliminate the blocking artifacts associated with RRU, RRU+ provides better peak signal-to-noise ratio (PSNR) performance than RRU, whereas RRU with maximum deblocking strength degrades the PSNR performance compared to RRU. Results comparing H.264 with RRU/RRU+ are also presented and the effectiveness of RRU/RRU+ as a tool for improving coding efficiency is discussed. [ABSTRACT FROM AUTHOR]

Block-based motion estimation is widely used in video compression for exploiting video temporal redundancy. Although effective, the process is arguably the most computationally intensive part of a typical video encoder. To speed up the process, a large number of fast block-matching algorithms (BMAs) have been proposed for motion estimation by limiting the number of search locations or simplifying the measure of match between the two blocks under comparison. In this paper we propose a new BMA that measures the match by using such features as block sum and block variance, which can be easily computed using integral frame attributes. Experimental results show that the proposed BMA can reduce the computational complexity notably and achieve compression performance very close to that of existing BMAs using conventional block-matching measures. [ABSTRACT FROM AUTHOR]

Block-Wise processing of motion compensated interlaced-to-progressive conversion (MC-IPC) can cause spurious errors that degrade converted image quality significantly. This paper presents a novel IPC method based on motion adaptive IPC (MA-IPC) with its adaptation assisted by the motion compensation. The motion adaptation is performed with respect to a motion selected from a limited set based on the accuracy evaluated with a reduced and overlapped block. The use of the reduced and overlapped blocks makes evaluation of the accuracy more precise, and implementation less costly. The motion adaptation structure ensures that any possible error occurs pixel-wise so that the block-wise spurious errors can be eliminated. The estimation of the motion is performed efficiently with data already available for the motion adaptation. The proposed motion compensation assisted MA-IPC method provides image quality similar to the MC-IPC, for those images, the MC-IPC offers significant improvement over the MA-IPC, yet at considerably lower computational and implementation costs. [ABSTRACT FROM AUTHOR]

This paper presents a new block matching motion estimation algorithm and its VLSI architecture design. The pro- posed global elimination algorithm (GEA) was derived from successive elimination algorithm (SEA), which can skip unnecessary sum of absolute difference (SAD) calculation by comparing minimum SAD with subsampled SAD (SSAD). Our basic idea is to separate the decision of early termination and SAD calculation for each candidate block to make data flow more regular and suitable for hardware. In short, we first compare the rough characteristics of all candidate blocks with the current block (SSAD). In turn, we select several best roughly matched candidate blocks to re-compare them with the current block by using detailed characteristics (SAD). Other features of GEA include fixed processing cycles, no initial guess, and high video quality (almost the same as full search). Unlike other fast algorithms, the mapping of GEA to hardware is very simple. We proposed an architecture that is composed of a systolic part to efficiently compute SSAD, an adder tree to support both SSAD and SAD calculations, and a comparator tree to avoid expensive sorting circuits. Simulation results show that our design is much more area efficient than many full-search architectures while maintaining high video quality and processing capability. [ABSTRACT FROM AUTHOR]

The conventional variable-size block motion compensation technique, even though superior to the fixed-size block motion-compensation technique, cannot fully utilize the motion information of a frame for its partitioning. This paper presents a quadtree structured region-wise motion-compensation technique that utilizes more effectively the motion content of a frame in terms of the shape, size, and location of the partitioned regions. The proposed technique is based on a new coding scheme of the quadtree structure, where a two-bit code is used. The partitioning of a given frame is carried out through the processes of merging and combining. The merging process partitions the frame into a number of regions by carrying out all possible 4-to-1, 3-to-1, and 2-to-1 merges along the quadtree hierarchy according to some specified criteria, while the combining process combines some of the partitioned regions that have the same motion vector into a single region. The motion vectors of the resulting partitioned regions are coded by a new coding scheme that uses the temporal correlation of the motion fields. Test results of applying the proposed method on a number of MPEG video sequences are included. These results indicate that the proposed method can provide a significantly improved rate-distortion performance [ABSTRACT FROM PUBLISHER]