11110859
A locally-adaptive algorithm for measuring blocking artifacts in images and videos
Block transform coding is the most popular approach for image and video compression. The objective measurement of blocking artifacts plays an important role in the design, optimization, and assessment of image and video coding systems. This paper presents a new algorithm for measuring blocking artifacts in images and videos. It exhibits unique and useful features: 1) it examines the blocks individually so that it can measure the severity of blocking artifacts locally; 2) it is a one-pass algorithm in the sense that the image needs to be accessed only once; 3) it takes into account the blocking artifacts for high bit rate images and the flatness for the very low bit rate images; 4) the blocking artifacts measure is well-defined in the range of 0-10. Experiments on various still images and videos show that this blockiness measure is very efficient in terms of computational complexity and memory usage, and can produce consistent blocking artifacts measurement.
9260921
Complexity adaptive quantization for intra-frames in very low bit rate video coding
Conventional rate control schemes focus on the problem of finding an optimal quantization value for P- and B-frames. No rate control is available for the encoding of I-frames. This could pose big problems due to the large number of bits an I-frame could generate, and due to the fact that the number of bits varies drastically from sequence to sequence, depending on their image complexity. This problem becomes severe especially at very low bit rate. Therefore, a mechanism to allocate data bits to an I-frame according to its complexity is indispensable in order to have constant coding quality. This work presents a mechanism to establish for I-frames a generic relationship between the quantization value, data bits, and their image complexity. Experimental results show that this generic relationship provides a fairly accurate estimation of quantization value for an I-frame at given data bits and image complexity, and is very useful in controlling the data bits generated by an I-frame.
18071478
A perceptual bit allocation scheme for H.264
This paper aims at improving perceptual quality of encoded video sequences, and proposes a new perceptual bit allocation scheme for H.264. Firstly, a new motion complexity measure is defined to represent the amount of motion contents between two consecutive frames, and is used to estimate the target bit at frame level. Secondly, a segmentation method exploiting the perceptual characteristics of the video contents is presented, and is used to adaptively update the Lagrangian multiplier in the coding mode selection at macroblock level. Thirdly, based on the motion complexity and Lagrangian multiplier updating, a rate control scheme for H.264 is proposed. Experimental results show that our scheme can effectively improve the perceptual video quality as compared with the H.264 adopted rate control algorithm. Moreover, our scheme also achieves an average peak signal-to-noise ratio gain of up to 0.138 dB for the test sequences.
13046627
Adaptive frame skipping based on spatio-temporal complexity for low bit-rate video coding
Abstract Conventional rate control schemes focus on the adjustment of quantization values to retain a certain buffer level, and buffer adaptive frame skippings are used to avoid buffer overflow at low bit-rates. In this paper, an adaptive frame-skipping scheme is proposed to achieve the balance between spatial and temporal quality, and to maintain the buffer level. The occurrence of frame skipping is jointly dependent on the temporal and spatial complexity of the video, and on the fullness of the buffer. This helps to achieve a balanced spatial and temporal quality and to enhance the overall perceptual quality. Experimental results show that the new scheme is simple but very effective, with large average PSNR gains and consistently improved visual quality, and the improvement in perceptual quality is much significant than that in average PSNRs.
39269573
An adaptive edge-preserving artifacts removal filter for video post-processing
We propose an adaptive edge-preserving artifacts removal filter (EPARF) for post-processing video compressed using block-based motion compensation so as to improve visual quality. The proposed filter is based on half-quadratic regularization, and it can adaptively remove both blocking and ringing artifacts while preserving object edges. The proposed algorithm has been applied to video sequences compressed by the MSRA scalable video coding (SVC) codec with block-based motion-compensated temporal filtering (MCTF). Experimental results demonstrate that EPARF can significantly improve both subjective and objective quality.
22420647
Adaptive intra-frame quantization for very low bit rate video coding
This paper presents, for I-frames, a generic relationship among the quantization value, data bits, and their spatial complexity. This relationship provides a mechanism to select the quantization value for an I-frame (with different spatial complexity) at given bit budget before actually encoding it. Therefore it helps to adaptively distribute the bit budget among I-, P- and B-frames in a sequence. Experiments show that the adaptive intra frame quantization algorithm reduces the number of frame skippings significantly with comparable average PSNRs, and thus improves the overall subjective quality of the reconstructed video.
8585778
Web-based infectious disease reporting using XML forms
OBJECTIVE
Exploring solutions for infectious disease information sharing among hospital and public health information systems is imperative to the improvement of disease surveillance and emergent response. This paper aimed at developing a method to directly transmit real-time data of notifiable infectious diseases from hospital information systems to public health information systems on the Internet by using a standard eXtensible Markup Language (XML) format.


METHODS
The mechanism and work flow by which notifiable infectious disease data are created, reported and used at health agencies in China was evaluated. The capacity of all participating providers to use electronic data interchange to submit transactions of data required for the notifiable infectious disease reporting was assessed. The minimum data set at national level that is required for reporting for national notifiable infectious disease surveillance was determined. The standards and techniques available worldwide for electronic health data interchange, such as XML, HL7 messaging, CDA and ATSM CCR, etc. were reviewed and compared, and an XML implementation format needed for this purpose was defined for hospitals that are able to access the Internet to provide a complete infectious disease reporting.


RESULTS
There are 18,703 county or city hospitals in China. All of them have access to basic information infrastructures including computers, e-mail and the Internet. Nearly 10,000 hospitals possess hospital information systems used for electronically recording, retrieving and manipulating patients' information. These systems collect 23 data items required in the minimum data set for national notifiable infectious disease reporting. In order to transmit these data items to the disease surveillance system and local health information systems instantly and without duplication of data input, an XML schema and a set of standard data elements were developed to define the content, structure and semantics of the data set. These standards make it possible to view and analyse the data accurately outside the hospital information systems in many different document formats. The paper also identified other issues involved in notifiable disease reporting in the future, such as the adoption of approved vocabulary standards and implementation problems such as the route, secure transfer, parsing, and objective identifying of the XML message.


CONCLUSIONS
XML is an increasingly important standard for exchange and transmission of data between disparate applications and systems. As in its early stages of developing an interoperable health information system in China, the XML document structures could be a way to exchange the notifiable case information among interest parties on the web at present.
10609537
A new set of moment invariants for handwritten numeral recognition
In this paper, a new set of aspect invariant moments for handwritten numeral recognition are presented. These new moments exhibit two useful properties. Firstly, they are aspect invariant. This eliminates the need for size normalization of the unconstrained numerals. Secondly, their dynamic range remains constant with moment order. This overcomes the problem of diminishing high order moments, which occurs when other moment invariants are used. Thus, aspect invariant moments are particularly suitable for use with neural networks. Experimental results (using a multilayer perceptron and the backpropagation learning rule) show that a very high recognition rate (98.73%) and low substitution rate (1.06%) can be achieved on a totally unconstrained handwritten numeral database.<<ETX>>
13300465
Robust sequence memory in sparsely-connected networks with controllable steady-state period
A novel sparsely-connected neural network for sequence memory with controllable steady-state period is proposed in this study. By introducing a new exponential kernel sampling function and the sampling interval parameter, the steady-state period can be controlled, and the steady-state time steps is equal to the sampling interval parameter. Ascribing to the exponential kernel sampling function, the sequence storage capacity is enlarged compared with the existing sequence memory models. Owning to the sparsely-connected of Gaussian distribution, the model produces the efficient use of synapse resources, but the sequence storage capacity is decreased compared with the fully-connected networks. The study also gives a significant result that the networks of different dimensions have the same synapse connection efficiency if they are with the same connection mean degree.
41075889
Efficient Compression of Multi-view Video Using Hierarchical B Pictures
3D and free viewpoint video are new types of natural video media that expand the user's sensation far beyond what is offered by traditional media. As video compression is a key issue in traditional video communications and the use of multi video streams makes it even more important for such applications. In this paper, we presented an investigation of the multi- view video coding structures with focus on exploiting hierarchical B pictures. We demonstrate hierarchical B pictures prediction structures, and present the advantage of several multi-view video coding prediction schemes. This demonstration will show the benefits of using hierarchical B pictures based on H.264/AVC. The simulation results demonstrate that the objective quality can be improved with the advanced MVC prediction structures in comparison to the simulcast coding structures.
3020798
Statistical learning makes the hybridization of particle swarm and differential evolution more efficient—A novel hybrid optimizer
This brief paper reports a hybrid algorithm we developed recently to solve the global optimization problems of multimodal functions, by combining the advantages of two powerful population-based metaheuristics—differential evolution (DE) and particle swarm optimization (PSO). In the hybrid denoted by DEPSO, each individual in one generation chooses its evolution method, DE or PSO, in a statistical learning way. The choice depends on the relative success ratio of the two methods in a previous learning period. The proposed DEPSO is compared with its PSO and DE parents, two advanced DE variants one of which is suggested by the originators of DE, two advanced PSO variants one of which is acknowledged as a recent standard by PSO community, and also a previous DEPSO. Benchmark tests demonstrate that the DEPSO is more competent for the global optimization of multimodal functions due to its high optimization quality.