The H.264/AVC standard employs the predictive motion vector coding technique using the median predictor of spatially neighboring three motion vectors. Although the median is effective in reducing redundancy, it is not...
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The H.264/AVC standard employs the predictive motion vector coding technique using the median predictor of spatially neighboring three motion vectors. Although the median is effective in reducing redundancy, it is not always optimal in minimizing bits. To solve the matter, a new motion vector coding scheme, known as, MV competition in which decoder is signaled on the selected optimal PMV, has been reported. Though it can use the optimal PMV(Predicted Motion Vector), the bits consumed to indicating the optimal PMV to the decoder increases bit-rate. In this paper, we propose a new motion vector coding scheme that allows usage of an optimal PMV without consuming additional bits to inform the choice of PMV to decoder. Simulation results show that the proposed method gains in BDBR by 3.22% on average, and in BDPSNR by 0.13 dB compared to the H.264/AVC.
Steganography is the art and science of hiding secret data to provide a safe communication between two parties and it is a prominent branch in the information hiding research area. This paper presents a new steganogra...
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Steganography is the art and science of hiding secret data to provide a safe communication between two parties and it is a prominent branch in the information hiding research area. This paper presents a new steganographic method based on predictive coding and embeds secret message in quantized error values via quantization index modulation (QIM). The proposed method is superior to previous methods in that it can make a satisfying balance among the most concerned criteria in steganography which are imperceptibility, hiding capacity, compression ratio and robustness against attacks. The performance of the proposed method is evaluated by several experiments on gray-level images with different textural properties. The new method is also compared with two renowned steganographic methods namely Jsteg and steganography based on predictive coding (SBPC). The results obtained from the experiments show that the proposed method has high visual quality and less histogram distortion while it has satisfactory compression ratio and embedding size.
We propose probabilistic method to determine motion vector (MV) for block matching algorithm (BMA). Proposed method allow us to exploit random distribution of motion vector in successive video frames for selection of ...
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We propose probabilistic method to determine motion vector (MV) for block matching algorithm (BMA). Proposed method allow us to exploit random distribution of motion vector in successive video frames for selection of initial search points for first iteration and refinement stage used in further iteration tracks motion vector in continuously changing video sequence. In our proposed algorithm due to adaptive step size it is able to track motion vectors of low motion as well as high motion video. The Simulation result shows that our proposed algorithm Probability based search motion estimation (PBSME) outperforms all sub-optimal motion estimation (ME) algorithms in terms of quality and speed up performance and in many cases PSNR of proposed algorithm is comparable to Full Search with several times faster.
In this paper, we investigate whether different scanning pattern affect the image quality reconstructed from adaptive quantization processing. Different space filling curves, such as Peano curve, Hilbert curve, Moore ...
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In this paper, we investigate whether different scanning pattern affect the image quality reconstructed from adaptive quantization processing. Different space filling curves, such as Peano curve, Hilbert curve, Moore curve, are implemented and compared in terms of compression ratio as well as image quality expressed in PSNR. The investigated space filling curves preserve the spacial neighborhood property of the pixel array, which is useful for predictive coding. While using those space filling curves, higher reconstructed image quality can be expected compared with the traditional raster scanning scheme.
Technological advances have made possible a number of new applications in the area of 3D video. One of the enabling technologies for many of these 3D applications is multiview video coding, which has received signific...
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Technological advances have made possible a number of new applications in the area of 3D video. One of the enabling technologies for many of these 3D applications is multiview video coding, which has received significant attention in the last several years. However, the fundamental need of multiview coding for applications like immersive tele-conferencing has not been addressed. In this paper we define the boundaries of the problem, and show how a simple algorithm can yield gains of up to 2times reduction in bitrate with similar PSNR in the synthesized view. Our algorithm is based on using an estimate of the viewer position to compute the expected contribution of each pixel to the synthesized view, and encoding each macroblock of each camera views with quality proportional to the likelihood that the pixel will be used in the synthetic image.
In this paper, we investigate into a new lossless compression framework for video. We are to exploit fuller scale of temporal redundancy, and propose an adaptive optimal compression plane (OCP) determination process t...
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In this paper, we investigate into a new lossless compression framework for video. We are to exploit fuller scale of temporal redundancy, and propose an adaptive optimal compression plane (OCP) determination process to be used with the standard intra-frame lossless predictive coding scheme. The essence of the scheme is to perform the prediction on the plane formed by two axes (among X, Y and T) corresponding to signal correlation evaluation, which enables better prediction (therefore better compression). In spite of the simplicity of the proposed method, simulation results show that the rate saving of the resultant system is 27.0% on average with respect to JPEG-LS, for a large number of videos with different visual content.
H.264/AVC is a novel video coding standard that provides better coding efficiency than previous video coding standards. It adopts many predictive coding algorithms to improve the coding efficiency of intra and inter f...
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H.264/AVC is a novel video coding standard that provides better coding efficiency than previous video coding standards. It adopts many predictive coding algorithms to improve the coding efficiency of intra and inter frames. Due to its characteristics of high compressibility, it can achieve high quality at low bit rate. Therefore, more and more applications adopt H.264/AVC codec. Nowadays, a great deal of researches has focused on copyright protection and digital authentication for H.264/AVC codec. In this paper, we propose a video watermarking scheme for H.264/AVC. Since our scheme only requires little extra computation, it can be easily implemented in encoder to perform real-time computation. As for bit rate increasing and degression of perceptual quality, the proposed scheme can control them within a fine degree. Simulation results demonstrate the performance of the proposed scheme.
In this paper, we propose a multiple description coding (MDC) method for reliable transmission of compressed time consistent 3D dynamic meshes. It trades off reconstruction quality for error resilience to provide the ...
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In this paper, we propose a multiple description coding (MDC) method for reliable transmission of compressed time consistent 3D dynamic meshes. It trades off reconstruction quality for error resilience to provide the best expected reconstruction of 3D mesh sequence at the decoder side. The method is based on partitioning the mesh vertices into two sets and encoding each set independently by a 3D dynamic mesh coder. The encoded independent bitstreams or so called descriptions are transmitted independently. The 3D dynamic mesh coder is based on predictive coding with spatial and temporal layered decomposition. In addition, the proposed method allows for different redundancy allocations by duplicating a number of encoded spatial layers in both sets. The algorithm is evaluated with redundancy-rate-distortion curves and flexible trade-off between redundancy and side distortions can be achieved.
Motivated by theoretical analysis of the curve fitting problem based on equivalent kernel, in this paper we propose a local adaptive learning and fusion model for side information interpolation in distributed video co...
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Motivated by theoretical analysis of the curve fitting problem based on equivalent kernel, in this paper we propose a local adaptive learning and fusion model for side information interpolation in distributed video coding. In the proposed model, each pixel in the interpolated frame is approximated as the linear combination of samples within a local spatio-temporal window using kernel parameters as weight. The size of training window can be adaptive to the motion characteristic of video, from samples in which the kernel parameters can be locally learned. In order to further improve the quality of interpolated frames, we introduce a belief-projection based fusion strategy with adaptive weights for multiple interpolated results which are with the same time index. Experimental results demonstrate that the proposed learning and fusion model is effective in performance for side information interpolation in distributed video coding.
Standard hybrid video coding systems are based on motion compensated prediction with fractional pel displacement vector resolution. In H.264/AVC, a fixed 6-tap interpolation filter is used to generate the half-pel res...
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ISBN:
(纸本)0819459763
Standard hybrid video coding systems are based on motion compensated prediction with fractional pel displacement vector resolution. In H.264/AVC, a fixed 6-tap interpolation filter is used to generate the half-pel resolution referenced blocks. Considering the non-stationary statistical properties of picture sequences, some adaptive interpolations are introduced in published papers. A practical scheme is proposed to use a three-parameter 1D filter for a whole frame subject to the statistical properties of the source pictures. The problem for such approach is that a universal filter for the whole picture can not adapt to the local changes, it is not considered as the optimal solution to the prediction. In this paper, a local adaptive filter is proposed to adapt to the local statistics of the picture structure. 2D Wiener-Hopf filter of different sizes are simulated to show the possibility of decreasing the prediction error. A better performance to the prediction error as well as the total coding performance compared to the 1D adaptive filtering can be achieved.
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