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排序方式: 共有538条查询结果,搜索用时 15 毫秒
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142.
Most of the traditional histogram-based thresholding techniques are effective for bi-level thresholding and unable to consider spatial contextual information of the image for selecting optimal threshold. In this article a novel thresholding technique is presented by proposing an energy function to generate the energy curve of an image by taking into an account the spatial contextual information of the image. The behavior of this energy curve is very much similar to the histogram of the image. To incorporate spatial contextual information of the image for threshold selection process, this energy curve is used as an input of our technique instead of histogram. Moreover, to mitigate multilevel thresholding problem the properties of genetic algorithm are exploited. The proposed algorithm is evaluated on the number of different types of images using a validity measure. The results of the proposed technique are compared with those obtained by using histogram of the image and also with an existing genetic algorithm based context sensitive technique. The comparisons confirmed the effectiveness of the proposed technique. 相似文献
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145.
基于区域直方图的图象数据库检索 总被引:1,自引:0,他引:1
文章提出了图象区域分割新方法,将图象空间信息与颜色信息有机结合。该方法可以以较少的数据描述一幅图象,有利于图象数据库的管理与检索;解决了尺度变化、旋转和平移不变性问题。 相似文献
146.
压缩视频基于内容检索系统的实现 总被引:3,自引:0,他引:3
文章介绍了以直方图为工具实现压缩视频基于内容检索系统的方法。其中包括:压缩视频DC图象的获得、DC图象的HSV颜色直方图表示、直方图实现镜头边缘检测、直方图实现镜头代表帧抽取以及代表帧的特征提取等。同时介绍了系统向用户提供的快速浏览功能和查询功能的实现。 相似文献
147.
A. El-Osery M. Jamshidi 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2002,7(2):97-106
Image enhancement is a field that is being used in various areas and disciplines. Advances in computers, microcontrollers
and DSP boards have opened new horizons to digital image processing, and have opened many avenues to the design and implementation
of new innovative techniques. This paper compares image enhancement via the modification of the probability density function
of the gray levels with the new techniques that involves the use of knowledge-base (fuzzy expert) systems that are capable
of mimicking the behavior of a human expert. A fuzzy expert system based software for image enhancement, called SmartPhotoLab has been introduced for the above purpose.
Present address: A. El-Osery Dept. of Electrical Engineering, New Mexico Tech, Workman Center Rm. 247 801 Leroy place, Socorro, NM 87801
e-mail: elosery@ee.nmt.edu.
This work was supported in parts by NASA grants no. NAG2–1196 and 2-1480. 相似文献
148.
In this paper, we have presented a high-payload, reversible data hiding scheme that is focused on embedding secret data into joint photographic experts group (JPEG) bitstream by using histogram modification. In JPEG, for AC coefficients, 162 different variable length codes (VLCs) are defined and assigned by Huffman coding for all 162 run/size possibilities. After parsing VLC usage in the bitstream, we generated a histogram of run/size. According to a peak point and the nearest zero point of the histogram, the secret data were embedded by modifying the corresponding VLC values slightly. The experimental results and comparing the performance of our scheme with those of other existing schemes demonstrated that the proposed scheme preserved the quality of the image with no distortion and achieved the goal of high embedding capacity. 相似文献
149.
实现医学超声图像的自动化定量分析.设计并实现一个基于人机交互的医学超声图像辅助分析系统.首先由医生凭借临床经验在超声图像中划出目标区域,系统生成目标子图像,然后使用直方图均衡和迭代阈值法对目标子图像进行灰度调整和分割处理,最后根据位图标记结果在原图中提取目标轮廓,并自动生成反映目标大小的长、宽等数据.通过采用一定的图像处理技术,成功地实现了对超声图像中目标区域的分割和自动化定量分析.本系统能弥补当前超声图文管理系统在图像分割和图像分析方面的不足,具有较高的实用性. 相似文献
150.
Reversible watermarking method based on asymmetric-histogram shifting of prediction errors 总被引:1,自引:0,他引:1
This paper tries to provide a new perspective for the research of reversible watermarking based on histogram shifting of prediction errors. Instead of obtaining one prediction error for the current pixel, we calculate multiple prediction errors by designing a multi-prediction scheme. An asymmetric error histogram is then constructed by selecting the suitable one from these errors. Compared with traditional symmetric histogram, the asymmetric error histogram reduces the amount of shifted pixels, thus improving the watermarked image quality. Moreover, a complementary embedding strategy is proposed by combining the maximum and minimum error histograms. As the two error histograms shift in the opposite directions during the embedding, some watermarked pixels will be restored to their original values, thus the image quality is further improved. Experimental findings also show that the proposed method re-creates watermarked images of higher quality that carry larger embedding capacity compared to conventional symmetric histogram methods, such as Tsai et al.’s and Luo et al.’s works. 相似文献