A coding-cost framework for super-resolution motion layer decomposition

We consider the problem of decomposing a video sequence into a superposition of (a given number of) moving layers. For this problem, we propose an energy minimization approach based on the coding cost. Our contributions affect both the model (what is minimized) and the algorithmic side (how it is minimized). The novelty of the coding-cost model is the inclusion of a refined model of the image formation process, known as super resolution. This accounts for camera blur and area averaging arising in a physically plausible image formation process. It allows us to extract sharp high-resolution layers from the video sequence. The algorithmic framework is based on an alternating minimization scheme and includes the following innovations. 1) A video labeling, we optimize the layer domains. This allows to regularize the shapes of the layers and a very elegant handling of occlusions. 2) We present an efficient parallel algorithm for extracting super-resolved layers based on TV filtering.     

The digital TV filter and nonlinear denoising.

Motivated by the classical TV (total variation) restoration model, we propose a new nonlinear filter-the digital TV filter for denoising and enhancing digital images, or more generally, data living on graphs. The digital TV filter is a data dependent lowpass filter, capable of denoising data without blurring jumps or edges. In iterations, it solves a global total variational (or L(1)) optimization problem, which differs from most statistical filters. Applications are given in the denoising of one dimensional (1-D) signals, two-dimensional (2-D) data with irregular structures, gray scale and color images, and nonflat image features such as chromaticity.     

MPEG-2传输流中I-帧的统计分析

I-帧为MPEG定义的一种图像格式，它的应用场合比较广泛，比如基于视频内容检索的多媒体系统、视频节目的特技播放，给出一种对MPEG-2传输流中I-帧分布的统计方法，对3段数字电视节目进行实验，得到节目流中I-帧的分布情况，包括I-帧的大小、间隔等，并且分析了TS流中I-帧分布的特点。     

DTV图像清晰度与图像格式变换、同心度和重显率的关系

针对基于电子束扫描的CRT电视显像管和基于像素寻址的LCD、PDP、DLP和LCoS等固有分辨力显示器，分析了它们显示数字电视图像的区别，重点研讨了固有分辨力显示器像素阵列、同心度、重显率和图像格式变换对重显图像清晰度的影响，给出了部分实验结果，提出了改善数字电视图像清晰度的建议。     

Total Variation for Image Restoration with Smooth Area Protection

The problem for image restoration is usually reduced to a constraint optimization problem. Different choice of optimization operator leads to various restoration models, e.g. least squares model and original total variation (TV) model. The TV model and its modified version can efficiently preserve the edge of the restored image well, but there exist obvious staircases in smooth area of the restored image. To reduce those staircases, we propose a new modified TV model, by adding a constraint term for smooth area protection as a penalty function. The numerical experiment shows our model can not only preserve the edge as well as TV model, but also efficiently reduce the staircase appearing in the smooth areas. Furthermore, It is shown that the restored image by our model has higher signal-to-noise ratio, less mean square error and better visual effect than those by the least squares model and by the TV models.     

电视图像的视觉传达设计研究

针对高清电视数字图像边缘对比度低、清晰显示难度大的问题,提出考虑视觉传达效果的二维灰度电视图像直方图边缘显示方法.首先对包含大量扰动信息和各类噪声的电视图像进行预处理,识别信号模式并进行特征提取;根据电视图像特征及灰度梯度在图像边缘的响应,获取直方图的统计特征并进行分块处理,形成二维灰度图像的直方图;搜寻出二维灰度图像直方图与电视数字图像边缘的内在关联性,实现对电视图像边缘的精确显示.实验结果证明,提出的电视图像边缘显示方法能够获得更好的视觉传达效果.     

图像超分辨率重建处理算法研究

超分辨算法为实现图像和视频分辨率提高的一种方法。其广泛应用于数字电视、医学图像处理、军事与遥感等领域。超分辨率图像通过融合多帧相似的低分辨率图像达到提高图像细节的目的。本文对使用较为普遍的频域方法、非均匀差值算法、凸集投影算法、迭代反投影算法、最大后验概率方法及基于学习的方法进行了分析,并简要讨论了超分辨算法未来的发展方向。     

Fast minimization methods for solving constrained total-variation superresolution image reconstruction

In this paper, we study the problem of reconstructing a high-resolution image from several decimated, blurred and noisy low-resolution versions of the high-resolution image. The problem can be formulated as a combination of the total variation (TV) inpainting model and the superresolution image reconstruction model. The main purpose of this paper is to develop an inexact alternating direction method for solving such constrained TV image reconstruction problem. Experimental results are given to show that the proposed algorithm is effective and efficient.     

一种超高清激光电视系统的设计方案

文章介绍一种超高清激光电视系统的设计方案,详细阐述了方案的设计原理.系统TV SOC模块将电视信号处理成像素为4M×2N@f的超高清图像信号,图像处理模块对超高清图像信号进行采样、分割和倍频处理后得到2路（√2 M×√2）N@2f的高清图像信号,DMD驱动模块对2路高清图像信号进行合并处理得到（2√2M×√2N@2f）图像信号来驱动DMD芯片,DMD芯片投射出分辨率为（2√2M×√2N）的图像光;采用振镜使DMD投射的相邻帧图像光位置微移,从而显示出4M×2N@f的合成画面.该方案可以快速应用于超高清激光电视产品,具有广泛应用价值.     

The information content of MR images

The theoretical information content, defined by C.E. Shannon (1948), is proposed as an objective measure of MR (magnetic resonance) image quality. This measure takes into account the contrast-to-noise ratio (CNR), scan resolution, and field of view. It is used to derive an optimum in the tradeoff problem between image resolution and CNR, and as a criterion to assess the usefulness of high-resolution (512(2)) MR images. The result tells that for a given total acquisition time, an optimum value of the resolution can be found. This optimum is very broad. To apply Shannon's theory on information constant to MR images, a model for the spatial spectral power density of these images is required. Such a model has been derived from experimental observations of ordinary MR images, as well as from theoretical considerations.     

一种基于积分微分方程的泊松噪声去除算法

该文提出一种新的基于积分微分方程的泊松噪声去除算法.首先讨论了经典的总变差(TV)最小模型,在此基础上提出一种新的变分多尺度分层图像表示方法,然后在逆尺度空间上积分“尺度”图像从而得到了新的积分微分方程.这种新的积分微分方程含有一个单调增加的尺度函数.通过选取适当的尺度函数,该方程可以有效地去除泊松型噪声.数值实验证明了该算法比经典的TV和四阶偏微分方程算法具有更好的去噪效果.     

Data Specific Spatially Varying Regularization for Multimodal Fluorescence Molecular Tomography

Fluorescence molecular tomography (FMT) allows in vivo localization and quantification of fluorescence biodistributions in whole animals. The ill-posed nature of the tomographic reconstruction problem, however, limits the attainable resolution. Improvements in resolution and overall imaging performance can be achieved by forming image priors from geometric information obtained by a secondary anatomical or functional high-resolution imaging modality such as X-ray computed tomography or magnetic resonance imaging. A particular challenge in using image priors is to avoid the use of assumptions that may bias the solution and reduced the accuracy of the inverse problem. This is particularly relevant in FMT inversions where there is not an evident link between secondary geometric information and the underlying fluorescence biodistribution. We present here a new, two step approach to incorporating structural priors into the FMT inverse problem. By using the anatomic information to define a low dimensional inverse problem, we obtain a solution which we then use to determine the parameters defining a spatially varying regularization matrix for the full resolution problem. The regularization term is thus customized for each data set and is guided by the data rather than depending only on user defined a priori assumptions. Results are presented for both simulated and experimental data sets, and show significant improvements in image quality as compared to traditional regularization techniques.      

PAL信号三维谱结构与特征的分析

根据电视图像的相关特性，对PAL信号的三维谱结构及其特征进行了数学分析。按照运动相对性原理，阐述了运动图像的频谱按瞬时离散状分布的这一特征规律。     

保持图形拓扑特性的激光雕刻算法

光刻槽的补偿问题在激光雕刻中有着重要意义，以往的光刻槽补偿算法由于没有考虑到图形遥拓扑特性，从而引入了拓扑噪音，使得输出分辨率降低。本文从数学形态学的理论出发，提出了一种同伦粗化的补偿算法，在实践中取得了良好的效果。     

一种基于数学形态学的电视图像分割方法

针对电视图像信噪比低,噪声干扰大的特点,提出了一种基于数学形态学的电视图像分割方法。首先利用基于梯度调整的平均灰度法得到图像的阀值,其次利用该灰度阀值二值化图像,最后对该图像利用数学形态学消除噪声。实验结果表明该方法具有较好的滤波效果,计算时间短,可用于实时图像处理中。     

Phase-Adaptive Superresolution of Mammographic Images Using Complex Wavelets

This correspondence describes a new superresolution approach for enhancing the resolution of mammographic images using complex wavelet frequency information. This method allows regions of interest of a mammographic image to be viewed in enhanced resolution while reducing the patient exposure to radiation. The proposed method exploits the structural characteristics of breast tissues being imaged and produces higher resolution mammographic images with sufficient visual fidelity that fine image details can be discriminated more easily. In our approach, the superresolution problem is formulated as a constrained optimization problem using a third-order Markov prior model and adapts the priors based on the phase variations of the low-resolution mammographic images. Experimental results indicate the proposed method is more effective at preserving the visual information when compared with existing resolution enhancement methods.     

Evaluation of both image resolution and contrast-to-noise ratio in scanning electron microscopy

The contrast-to-gradient (CG) resolution has been defined as a weighted harmonic mean of the local resolution, i.e. the length defining the object's local fine structure at each pixel position. The newly defined resolution Res is defined as 2 sigma/ sqrt 2, where 2 sigma is a sharpness factor of the image pattern obtained by the conversion 2 sigma = ARCG + B using default constants A and B. In the present study, we have extended the algorithm to change the constants from default values to calibrated ones using standard images that are same in both pattern and contrast-to-noise ratio (CNR) as the original SEM image to be evaluated. The calibrated image resolution with a weak noise dependency is evaluated with the CNR as a given parameter.     

Fast Gradient-Based Algorithms for Constrained Total Variation Image Denoising and Deblurring Problems

This paper studies gradient-based schemes for image denoising and deblurring problems based on the discretized total variation (TV) minimization model with constraints. We derive a fast algorithm for the constrained TV-based image deburring problem. To achieve this task, we combine an acceleration of the well known dual approach to the denoising problem with a novel monotone version of a fast iterative shrinkage/thresholding algorithm (FISTA) we have recently introduced. The resulting gradient-based algorithm shares a remarkable simplicity together with a proven global rate of convergence which is significantly better than currently known gradient projections-based methods. Our results are applicable to both the anisotropic and isotropic discretized TV functionals. Initial numerical results demonstrate the viability and efficiency of the proposed algorithms on image deblurring problems with box constraints.     

Configurable Media Codec Framework： A Stepping Stone for Fast and Stable Codec Development

Recent advances in reconfigurable computing have led to new ways of implementing complex algorithms while maintaining reasonable throughput.Video codecs are becoming more complex in order to provide efficient compression for video with ever-increasing resolution.This problem is compounded by the fact that spectra of video decoding devices has become wider in the move from traditional TV to cable and satellite TV,IPTV,mobile TV,and Internet media.MPEG is tackling this problem with a reconfigurable video coding(RVC) framework and is standardizing a modular definition of tools and connections.MPEG’s work started with video coding and has recently extended to graphics data coding.RVC will be supported by non-MPEG standards such as the Chinese audio-video standard(AVS).This article gives a brief background to the reconfigurable codec framework.The key to this framework is reconfigurability and reducing granularity to find commonality between different standards.     

An effective color scale for simultaneous color and gray-scale publications

Pseudocolored images are used in many signal processing applications to represent signal properties as a function of two independent variables, such as time and frequency. This paper describes a color scale that can be used to unambiguously represent these images in printed gray-scale publications as well as full color electronic publications. The image resolution when viewed in color is enhanced in this article. This color scale also allows for correct interpretation by people with common types of color blindness, which accounts for approximately 10% of the male population and 1% of the female population. While it may be possible to obtain a better resolution with a color scale that is designed for a particular image on hand, the proposed color scale works well in many applications where the user does not have the time or resources to tailor the color scale to a specific image. The proposed color scale is also easy to implement and has an intuitive interpretation in that it cycles through a sequence of hues that roughly resembles the familiar rainbow.