This paper describes new statistical models of the JPEG lossless mode subject to the super high definition images (SHDI). Seven predictors prepared in the JPEG are very simple to alleviate the complexity of the predic...
详细信息
This paper describes new statistical models of the JPEG lossless mode subject to the super high definition images (SHDI). Seven predictors prepared in the JPEG are very simple to alleviate the complexity of the prediction process, which indicates that prediction residuals correlate. The actual correlation of the residuals exhibits a tendency to be more significant as the number of picture elements increases. Consequently, the conditional probability densities of the residual signals for SHDI differ from the Laplacian distribution commonly assumed in predictive coding. We propose two statistical models considering the peculiar probability densities and investigate the validity of the models by coding simulations.
predictive coding, also called Text Categorization, has been widely used in legal industry. By leveraging machine learning models such as logistic regression and SVM, the review of documents can be prioritized based o...
详细信息
ISBN:
(数字)9781728108582
ISBN:
(纸本)9781728108599
predictive coding, also called Text Categorization, has been widely used in legal industry. By leveraging machine learning models such as logistic regression and SVM, the review of documents can be prioritized based on their probability of relevance to the legal case, thus improving review efficiency and cutting cost. In recent years, deep learning models-combined with word embeddings-have shown better performance in predictive coding. However, deep learning models involve many parameters and it is challenging and time-consuming for legal practitioners to select appropriate settings. Based on the experiments on several public legal text datasets, this paper shows the preliminary results about how various key parameter settings impact the performance of Convolutional Neural Networks (CNNs).
I use an influential computational theory of brain function—the free-energy principle—to suggest three points of added complexity to Mark Solms’s intriguing descriptions of the embodied mind: (1) The link between e...
详细信息
The paper investigates the use of 2nd order geometric transformations for the purposes of motion compensation, in interframe image data compression schemes. An algorithm that calculates the mapping functions which des...
详细信息
The paper investigates the use of 2nd order geometric transformations for the purposes of motion compensation, in interframe image data compression schemes. An algorithm that calculates the mapping functions which describe the movements or changes that occur within blocks (cells) of the image from one frame to the next, is presented. Images from popular test sequences have been tried with this algorithm to test its performance, and the authors have included some of the results in the paper. A comparison with the conventional, translational motion compensation is also made.< >
Methods for object-based compression and composition of natural and synthetic video content are currently emerging in standards such as MPEG-4 and VRML. This paper describes novel techniques for compression of 2-D tri...
详细信息
Methods for object-based compression and composition of natural and synthetic video content are currently emerging in standards such as MPEG-4 and VRML. This paper describes novel techniques for compression of 2-D triangular mesh geometry and motion, enabling efficient representation and manipulation of video content. Specifically, mesh geometry is compressed by predictive coding of mesh node locations. Mesh node motion vectors are compressed by predictive techniques as well. Preliminary results show that the mesh data can be coded at a fraction of the bits used to code a typical video object.
We introduce an efficient algorithm for real-time compression of temporally consistent dynamic 3D meshes. The algorithm uses mesh connectivity to determine the order of compression of vertex locations within a frame. ...
详细信息
We introduce an efficient algorithm for real-time compression of temporally consistent dynamic 3D meshes. The algorithm uses mesh connectivity to determine the order of compression of vertex locations within a frame. Compression is performed in a frame to frame fashion using only the last decoded frame and the partly decoded current frame for prediction. Following the predictive coding paradigm, local temporal and local spatial dependencies between vertex locations are exploited. In this framework we present a novel angle preserving predictor and evaluate its performance against other state of the art predictors. It is shown that the proposed algorithm improves up to 25% upon the current state of the art for compression of temporally consistent dynamic 3D meshes.
In video communication systems based on motion-compensated predictive coding, transmission errors cause spatial and temporal distortion propagation during; the reconstruction of the video sequence at the receiver. Two...
详细信息
In video communication systems based on motion-compensated predictive coding, transmission errors cause spatial and temporal distortion propagation during; the reconstruction of the video sequence at the receiver. Two commonly used techniques to stop error propagation are (1) periodic refreshing by intra-frame coding and (2) retransmission. However, frequent intra-frame refreshing may be expensive in band-limited applications such as wireless video transmission. On the other hand, retransmission causes additional delay which may be intolerable in real-time applications. We present a novel video coding mode which we call transmitter receiver identical reference frame (TRIRF) based inter-frame coding. Under the assumption of the existence of a feedback channel, TRIRF-frame coding constructs a new type of reference frame from the correctly received data which is made identical both at the receiver and the transmitter. Motion estimation and compensation are based on the TRIRF-frame. Simulations show that TRIRF-frame coding prevents error propagation as effectively as intra-coding but with improve compression efficiency. We also propose a packetization scheme for the encoded video bit streams which enables rapid resynchronization of the decoder.
An image compression algorithm suitable for focal plane integration and its hardware implementation are presented. In this approach an image is progressively decomposed into images of lower resolution. The low resolut...
详细信息
ISBN:
(纸本)9781467302180
An image compression algorithm suitable for focal plane integration and its hardware implementation are presented. In this approach an image is progressively decomposed into images of lower resolution. The low resolution images are then used as the predictors of the higher resolution images. The prediction residuals are entropy encoded and compressed. This compression approach can provide lossless or lossy compression and the resulting bitstream is a fully embedded code. A switched-capacitor circuit is proposed to implement the required operations. A prototype has been implemented on a 0.5 μm CMOS process. Simulation and measurements results validating the proposed approach are reported.
We propose a predictive coding algorithm for lossy compression of digital halftones produced by clustered-dot dithering. In our scheme, the predictor estimates the size and shape of each halftone dot (cluster) based o...
详细信息
We propose a predictive coding algorithm for lossy compression of digital halftones produced by clustered-dot dithering. In our scheme, the predictor estimates the size and shape of each halftone dot (cluster) based on the characteristics of neighboring clusters. The prediction template depends on which portion, or sub-cell, of the dithering matrix produced the dot. Information loss is permitted through imperfect representation of the prediction residuals. For some clusters, no residual is transmitted at all, and for others, information about the spatial locations of bit errors is omitted. Specifying only the number of bit errors in the residual is enough to allow the decoder to form an excellent approximation to the original dot structure. We also propose a simple alternative to the ordinary Hamming distance for computing distortion in bi-level images. Experiments with 1024/spl times/1024 images, 8/spl times/8 dithering cells, and 600 dpi printing have shown that the coding algorithm maintains good image quality while achieving rates below 0.1 bits per pixel.
Image sequence prediction is widely used in image compression and transmission schemes such as differential pulse code modulation (DPCM). In traditional predictive coding, linear predictors are usually adopted to expl...
详细信息
Image sequence prediction is widely used in image compression and transmission schemes such as differential pulse code modulation (DPCM). In traditional predictive coding, linear predictors are usually adopted to exploit the inherent redundancy and correlation between neighboring pixels. However, due to the nonstationary and non-Gaussian nature of image sequences, linear predictors are not often very effective. As an alternative, Volterra predictor is able to compensate for the smoothing effects introduced by linear predictor. However, it suffers from noise that may be attributed to quantization errors or image acquisition devices. In this paper, we propose a novel nonlinear polynomial weighted median (PWM) predictor for image sequence prediction. The proposed PWM predictor is more robust to noise, while still retaining the information of higher-order statistics of pixel values. Experimental results illustrate that the PWM predictor yields better results than other predictors especially in noisy case. The proposed scheme can be incorporated in new predictive coding systems.
暂无评论