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The Hybrid encoder is trying to choose the better encoder between the Wavelet Difference Reduction (Type-W) and Simple Bit-plane (Type-B) to get the better results than pure Type-W or pure Type-B was proposed in previous research. In case that the most pixels are insignificant, Type-B will generate a long consecutive sequence of zero bits. By experimental results, the Modified Simple Bit-plane which...
Digital video is widely used in the mobile applications, where video compression technology is necessary to store or transmit the videos. High Efficiency Video Coding (HEVC) achieves the highest compression ratio while it costs huge computational complexity, in which rate-distortion (RD) cost calculation takes the majority. This paper presents a low-complexity RD estimation method for HEVC intra prediction...
In this paper, adaptive PU mode estimation algorithm is proposed to achieve a fast High Efficiency Video Coding (HEVC) encoding. According to HEVC standard, a picture is composed of a number of Coding Tree Units (CTU's). These CTUs are further divided in quadtree structure to form Coding Units (CUs), and CUs have one or more Prediction Units (PUs). The PU mode decision processing to find a best PU...
The problem of optimal real-time transmission of a Gauss-Markov source under constraints on the expected number of transmissions is considered. This setup is motivated by applications where transmission is sporadic and the cost of switching on the radio and transmitting is significantly more important than the size of the transmitted data packet. The structure of optimal transmission and estimation...
Optical flow or dense motion field representations provide an alternative to block based schemes and are capable of describing smooth motion flows without introducing any artificial block boundaries. However dense motion fields have not been widely adopted for video coding applications principally due to the prohibitive cost of communicating such detailed motion representations. In this paper our...
Depth coding in 3D video is unique in that its quality is measured by the view synthesis distortion (VSD) rather than its own depth distortion, which further complicates the coding optimization as VSD is related to both the depth and texture quality. We propose a parameter-free VSD model to directly estimate the impact of depth errors on VSD on the small block basis, given its depth distortion. The...
Lately, several algorithms have been proposed to automatically estimate the quality of video sequences, even some have been included in international standards. However, the majority only provide high performance under particular conditions and with certain types of degradations. Therefore, some proposals have been presented setting out the combination of various quality metrics to improve the performance...
Machine learning based link optimization of wireless communications often relies on past experience, accurate estimation of channel conditions, and theoretical performance models. Typically, theoretical models poorly match given situations, past experiences are limited, and spectrum sensing of noise and channel conditions pose many hurdles. Hence, traditional cognitive radio engines based on genetic...
In this paper, we propose a macro-block (MB) level rate control algorithm for low delay H.264/AVC video communication based on the ρ domain rate model. In the proposed algorithm, an exponential model is used to characterize the relation between ρ and the quantization step (Qstep) at the MB level, with which the quantization parameter (QP) for a MB can be obtained. Furthermore, a switched QP calculation...
To improve the performance and speed of Digital signal processing operations such as FFT (Fast Fourier Transform), DCT (Discrete Cosine Transform) and FIR (Finite Impulse Response). We can implement the arithmetic operations in a fused manner. By direct recoding of the sum of two numbers in Modified Booth, the Add-Multiply operator have been fused together to reduce the power consumption, hardware...
Despite the several efforts aiming at reducing the complexity, block motion estimation remains the most computationally demanding stage of video compression algorithms. This is particularly evident when sequences contain large displacements. Very large search windows are needed to achieve high quality coding when such critical conditions occur. This paper presents a block motion estimation technique...
With the development of 3D video technology, many studies have paid attention to compression efficiency and rate distortion performance. When 3D videos are transmitted over error-prone channels, they may suffer significant quality degradation. In this paper, we combine multiview video coding (MVC) with multiple description coding (MDC) for robust transmission. The proposed scheme can give full consideration...
This paper proposes a novel algorithm for online distributed dictionary learning, where a set of nodes is requested to collectively estimate a common dictionary via sequentially received data vectors. At each time instance, in which a new datum becomes available, the sparse representation of the data with respect to the estimated dictionary is computed locally at each node by employing a sparsity...
Probability estimation is an elementary building block of every statistical data compression algorithm. In practice probability estimation should be adaptive, recent observations should receive a higher weight than older observations. We present a probability estimation method based on exponential smoothing that satisfies this requirement. Our main contribution is a theoretical analysis for various...
Screen content videos increasingly gain the popularity due to the rapid advances in cloud and multimedia technologies, which in turn requires highly efficient screen content compression. A recent standard, namely SCC is under development in JCT-VC, Joint Collaborative Team on Video Coding between ISO/IEC and ITU-T. In SCC, the most efficient new coding tool is Intra block copy (Intra BC). In this...
Ideas from iterative decoding of concatenated channel codes are adopted for joint source-channel decoding. Extrinsic information from a soft-in/soft-out channel decoder is used as a-priori information for the new soft-in/soft-out source decoder. The source decoder processes soft channel outputs, extrinsic information from the channel decoder, and source-statistics and it computes extrinsic information...
Despite recent advances, the extraction of optical flow with large displacements is still challenging for state-of the-art methods. The approaches that are the most successful at handling large displacements blend sparse correspondences from a matching algorithm with an optimization that refines the optical flow. We follow the scheme of Deep-Flow [33]. We first extract sparse pixel correspondences...
This paper evaluates the coding efficiency of the HM 13.0 HEVC rate-distortion optimizing (RDO) encoder before and after the context-adaptive binary arithmetic coding (CABAC) engine is replaced with the context-based arithmetic coding (CBAC) engine of AVS 2.0. In addition, the rate errors are controlled by varying the bit length of the fractional part for the estimated bit in the rate estimation table...
Block-based Motion Estimation (ME) has been widely used in various video coding standards to remove temporal redundancy. However, this ME has limitation that it can only compensate for a parallel translation. Various methods have been proposed for other motions such as zooming. In recent years, 8K UHDTV (7,680 × 4,320 pixels) has been developed. Since 8K has large motion by zooming that is difficult...
In this paper, we estimate the Mutual Information Rate (MIR) for Two-Dimensional Magnetic Recording (TDMR) channel with input constraints by using the Generalized Belief Propagation (GBP) algorithm. The Voronoi channel model is considered in this paper. Since the main source of media noise in the TDMR channel is the boundary distortion of the bit area which is manifested in presence of transitions...
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