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71.
用迭代法消除数字图像放大后的模糊   总被引:7,自引:3,他引:4  
用迭代法对数字图像经过插值放大后产生的模糊问题进行了研究,把数字图像插值放大造成的模糊看成是点扩散函数与清晰图像卷积的结果,根据插值算法可以得到点扩散函数,由于数字图像解卷积是典型的解线性方程组的问题,用雅可比(Jacobi)迭代法得到了很好的结果。与频谱空间变换的方法相比,迭代法没有分母为0的问题和空间变换过程造成的舍入误差。  相似文献   
72.
灰度图像的子块压缩方法   总被引:2,自引:0,他引:2  
从灰度图像的局部几何特性出发,把图像中像素灰度相近或相同的区域当作一个整体处理,从而达到图像压缩的目的。计算机仿真实验表明,该方法可以获得产高的压缩比和峰值信噪比,有效地消除方块效应,很好地保持目标细节,具有较高的实用价值。  相似文献   
73.
Volatile compounds of raw beef from Asturiana de los Valles, Morucha, Parda Alpina, Pirenaica, and Retinta cattle breeds were studied. Steaks were packaged under 60% O2, 30% CO2, and 10% N2, and 53 volatile compounds were tentatively identified by purge‐and‐trap extraction and gas chromatography with mass spectrometry after 0, 5, 10, and 15 d of chill storage. The degradation of beef quality with increasing storage time was evidenced by the increase in 2,3,3‐trimethylpentane, 2,2,5‐trimethylhexane, 3‐octene, 3‐methyl‐2‐heptene, 2‐octene, and 2‐propanone and by the decrease in dimethyl sulfide. Consequently, some of the volatile compounds, which are believed to be formed by thermal degradation of meat, might be formed during chill storage, and the rate of formation of some was dependent on the specific compound.  相似文献   
74.
A theory is presented that explains how the visual system infers the lightness, opacity, and depth of surfaces from stereoscopic images. It is shown that the polarity and magnitude of image contrast play distinct roles in surface perception, which can be captured by 2 principles of perceptual inference. First, a contrast depth asymmetry principle articulates how the visual system computes the ordinal depth and lightness relationships from the polarity of local, binocularly matched image contrast. Second, a global transmittance anchoring principle expresses how variations in contrast magnitudes are used to infer the presence of transparent surfaces. It is argued that these principles provide a unified explanation of how the visual system computes the 3-D surface structure of opaque and transparent surfaces. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
75.
In this paper we suggest a new statistical method of correcting the results of hot-line experiments for the effects of background sources and we use the new method to reassess the adequacy of three probability distributions proposed in the literature for image spread from line sources. The data are from sources labelled with 125I in semi-thin resin sections 0·4-0·8 μm in thickness. The new method reveals that two of the models describe the empirical distributions more closely than earlier analysis had suggested, and it confirms an increasing relationship between half distance of image spread and the thickness of the source. However, it also confirms that considerable ‘inter hot-line’ experimental variation remains, even after background correction. This suggests that multiple experiments are needed to produce reliable estimates of half distance.  相似文献   
76.
Seasoned beef called Jangzorim in Korea is produced by boiling in soy sauce, and is a popular food in Korea. The aim of this study is to evaluate the microbial safety and physical qualities of sous vide processed seasoned beef, and the effect of nisin during storage. Sous vide processed packages with or without nisin (100 IU or 500 IU) were stored at 4 °C or 25 °C for 60 days, and samples measured for quality at regular intervals throughout this storage period. In the case of 25 °C storage, the number of mesophilic microorganisms in seasoned beef packages without nisin increased markedly, but with nisin there was no observed increase. Psychrotrophic microorganisms, anaerobic microorganisms, and B. cereus cells showed similar trends, although C. perfringens was not detected in all samples. At 25 °C storage, changes in the cutting force of packages containing nisin showed no significant change, packages without nisin decreased markedly. The colour of packages without nisin showed a drastic decrease in lightness (‘L’) while no changes were observed in packages with nisin.  相似文献   
77.
本文阐述了CMOS图像传感器的一般特征,详细介绍了黑白CMOS图像传感器芯片OV9120的性能、特点及工作原理,给出了OV9120在图像采集处理中的具体应用实例。  相似文献   
78.
Corner detection is a low-level feature detection operator that is of great use in image processing applications, for example, optical flow and structure from motion by image correspondence. The detection of corners is a computationally intensive operation. Past implementations of corner detection techniques have been restricted to software. In this paper we propose an efficient very large-scale integration (VLSI) architecture for detection of corners in images. The corner detection technique is based on the half-edge concept and the first directional derivative of Gaussian. Apart from the location of the corner points, the algorithm also computes the corner orientation and the corner angle and outputs the edge map of the image. The symmetrical properties of the masks are utilized to reduce the number of convolutions effectively, from eight to two. Therefore, the number of multiplications required per pixel is reduced from 1800 to 392. Thus, the proposed architecture yields a speed-up factor of 4.6 over conventional convolution architectures. The architecture uses the principles of pipelining and parallelism and can be implemented in VLSI.  相似文献   
79.
80.
为满足印前和艺术设计过程中的图像处理的需要,介绍一种基于CMYK(青-品红-黄-黑)颜色空间的图像在TIFF文件中的存储,以及对此类图像的通用处理方法。通过对TIFF文件内部结构的解析,了解如何才能准确地对一幅CMYK图像进行描述、存储和处理。另外,文中还给出使用libtiff函数库处理TIFF文件的样例。  相似文献   
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