690 research outputs found

    Security Analysis of Bit plane Level Image Encryption Schemes

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    A selective bit-plane encryption scheme was proposed for securing the transmission of image data in mobile environments with a claim that it provides a high security viz. the encryption of the four most significant bit-planes is sufficient for a high image data security. This paper presents the security analysis of the said encryption scheme and reports new important results. We perform the security analysis of the bit-level encryption by considering the normal images and their histogram equalised enhanced images. We consider different bit-plane aspects to analyse the security of the image encryption, and show that the encryption of the four most significant bit-planes is not adequate. The contents of the images can be obtained even when all the bit-planes except one least significant bit-plane are encrypted in the histogram equalised images as shown in the results. The bit-plane level security analysis seems very useful for the analysis of the bit-plane level image encryption schemes

    Medical image enhancement

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    Each image acquired from a medical imaging system is often part of a two-dimensional (2-D) image set whose total presents a three-dimensional (3-D) object for diagnosis. Unfortunately, sometimes these images are of poor quality. These distortions cause an inadequate object-of-interest presentation, which can result in inaccurate image analysis. Blurring is considered a serious problem. Therefore, “deblurring” an image to obtain better quality is an important issue in medical image processing. In our research, the image is initially decomposed. Contrast improvement is achieved by modifying the coefficients obtained from the decomposed image. Small coefficient values represent subtle details and are amplified to improve the visibility of the corresponding details. The stronger image density variations make a major contribution to the overall dynamic range, and have large coefficient values. These values can be reduced without much information loss

    Object Enhancement, Noise Reduction, Conversion and Collection of Spatiotemporal Image Data

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    In this report, a variety of cellular dynamics are enhanced and analyzed utilizing various algorithms and filter for contrast enhancement. This report will also illustrate the underlying complexities of processing compressed data received from certain type of sensors, their default applications, various methods in converting compressed data to compatible universal uncompressed formats allowed in scientific applications, various methods of image and video capture, guidelines in ethical image manipulation, various methods of frame extraction, and analyzing/processing video images. These methods and processes purposely utilize freeware and public domain software to lower the cost of reproducibility for all

    Color space analysis for iris recognition

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    This thesis investigates issues related to the processing of multispectral and color infrared images of the iris. When utilizing the color bands of the electromagnetic spectrum, the eye color and the components of texture (luminosity and chromaticity) must be considered. This work examines the effect of eye color on texture-based iris recognition in both the near-IR and visible bands. A novel score level fusion algorithm for multispectral iris recognition is presented in this regard. The fusion algorithm - based on evidence that matching performance of a texture-based encoding scheme is impacted by the quality of texture within the original image - ranks the spectral bands of the image based on texture quality and designs a fusion rule based on these rankings. Color space analysis, to determine an optimal representation scheme, is also examined in this thesis. Color images are transformed from the sRGB color space to the CIE Lab, YCbCr, CMYK and HSV color spaces prior to encoding and matching. Also, enhancement methods to increase the contrast of the texture within the iris, without altering the chromaticity of the image, are discussed. Finally, cross-band matching is performed to illustrate the correlation between eye color and specific bands of the color image

    Keselesaan ke tempat kerja mempengaruhi kualiti hidup masyarakat bandar di Mukim Kajang, Selangor

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    Keselesaan penduduk ke tempat bekerja boleh mempengaruhi kualiti hidup masyarakat. Kajian ini telah mengenalpasti bahawa keselesaan ke tempat bekerja merupakan aspek yang boleh menyumbang kepada kualiti hidup yang baik. Oleh itu, aspek keselesaan ke tempat kerja harus diambilkira dalam menilai kualiti hidup masyarakat di bandar. Permasalah kajian ini ialah isu ketidakselesaan penduduk ke tempat bekerja telah menyebabkan gangguan pada kualiti hidup. Objektif kajian ialah mengkaji persepsi penduduk di bandar terhadap keselesaan ke tempat kerja. Kajian dijalankan di Bandar Kajang dan Bandar Baru Bangi. Kaedah soal selidik telah digunakan di lapangan. Sejumlah 700 responden telah dipilih secara rawak bebas di kawasan kajian. Data-data yang dikumpul telah dianalisis menggunakan program SPSS. Hasil kajian mendapati paling ramai responden iaitu 135 orang bekerja di tempat lain-lain, 112 bekerja di Kajang,105 bekerja di Bandar Baru Bangi, 36 bekerja di Universiti Kebangsaan Malaysia dan 26 bekerja di Serdang. Analisis perkaitan antara jarak rumah ke tempat bekerja menunjukkan nilai khi kuasa dua sebanyak 89.329 dan signifikan pada aras 0.05 (p=0.000), perkaitan antara jarak rumah ke tempat kerja dengan tempoh terlibat kesesakan lalu lintas menunjukkan nilai khi kuasa dua sebanyak 227.568 dan signifikan pada aras 0.05 (p=0.000). Sejumlah 208 responden terganggu emosi semasa berhadapan dengan kesesakkan lalu lintas, manakala 150 menyatakan masih boleh bersabar. Seramai 359 responden menyatakan tidak selesa ke tempat kerja sekiranya berlaku kesesakan lalu lintas.Kajian merumuskan bahawa kajian keselesaan ke tempat kerja wajar digunakan sebagai penunjuk kualiti hidup masyarakat di bandar, berdasarkan konflik-konflik yang dialami penduduk di bandar semasa berinteraksi ke tempat bekerja

    Digital Image Processing

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    This book presents several recent advances that are related or fall under the umbrella of 'digital image processing', with the purpose of providing an insight into the possibilities offered by digital image processing algorithms in various fields. The presented mathematical algorithms are accompanied by graphical representations and illustrative examples for an enhanced readability. The chapters are written in a manner that allows even a reader with basic experience and knowledge in the digital image processing field to properly understand the presented algorithms. Concurrently, the structure of the information in this book is such that fellow scientists will be able to use it to push the development of the presented subjects even further

    X-Ray Image Processing and Visualization for Remote Assistance of Airport Luggage Screeners

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    X-ray technology is widely used for airport luggage inspection nowadays. However, the ever-increasing sophistication of threat-concealment measures and types of threats, together with the natural complexity, inherent to the content of each individual luggage make x-ray raw images obtained directly from inspection systems unsuitable to clearly show various luggage and threat items, particularly low-density objects, which poses a great challenge for airport screeners. This thesis presents efforts spent in improving the rate of threat detection using image processing and visualization technologies. The principles of x-ray imaging for airport luggage inspection and the characteristics of single-energy and dual-energy x-ray data are first introduced. The image processing and visualization algorithms, selected and proposed for improving single energy and dual energy x-ray images, are then presented in four categories: (1) gray-level enhancement, (2) image segmentation, (3) pseudo coloring, and (4) image fusion. The major contributions of this research include identification of optimum combinations of common segmentation and enhancement methods, HSI based color-coding approaches and dual-energy image fusion algorithms —spatial information-based and wavelet-based image fusions. Experimental results generated with these image processing and visualization algorithms are shown and compared. Objective image quality measures are also explored in an effort to reduce the overhead of human subjective assessments and to provide more reliable evaluation results. Two application software are developed − an x-ray image processing application (XIP) and a wireless tablet PC-based remote supervision system (RSS). In XIP, we implemented in a user-friendly GUI the preceding image processing and visualization algorithms. In RSS, we ported available image processing and visualization methods to a wireless mobile supervisory station for screener assistance and supervision. Quantitative and on-site qualitative evaluations for various processed and fused x-ray luggage images demonstrate that using the proposed algorithms of image processing and visualization constitutes an effective and feasible means for improving airport luggage inspection

    Evaluation of the color image and video processing chain and visual quality management for consumer systems

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    With the advent of novel digital display technologies, color processing is increasingly becoming a key aspect in consumer video applications. Today’s state-of-the-art displays require sophisticated color and image reproduction techniques in order to achieve larger screen size, higher luminance and higher resolution than ever before. However, from color science perspective, there are clearly opportunities for improvement in the color reproduction capabilities of various emerging and conventional display technologies. This research seeks to identify potential areas for improvement in color processing in a video processing chain. As part of this research, various processes involved in a typical video processing chain in consumer video applications were reviewed. Several published color and contrast enhancement algorithms were evaluated, and a novel algorithm was developed to enhance color and contrast in images and videos in an effective and coordinated manner. Further, a psychophysical technique was developed and implemented for performing visual evaluation of color image and consumer video quality. Based on the performance analysis and visual experiments involving various algorithms, guidelines were proposed for the development of an effective color and contrast enhancement method for images and video applications. It is hoped that the knowledge gained from this research will help build a better understanding of color processing and color quality management methods in consumer video

    Automatic Detection and Segmentation of Lentil Breeding Plots from Images Captured by Multi-spectral UAV-Mounted Camera

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    Automatic Detection and Segmentation of Lentil Breeding Plots from Images Captured by Multi-spectral UAV-Mounted Camer

    Automatic Detection and Segmentation of Lentil Breeding Plots from Images Captured by Multi-spectral UAV-Mounted Camera

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    Automatic Detection and Segmentation of Lentil Breeding Plots from Images Captured by Multi-spectral UAV-Mounted Camer
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