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Efficient adaptive arithmetic coding based on updated probability distribution for lossless image compression

JOURNAL OF ELECTRONIC IMAGING 2010年第2期19卷

作者： Masmoudi, Atef Puech, William Bouhlel, Mohamed Salim Higher Inst Biotechnol Sci & Technol Images & Tel Sfax 3038 Tunisia Univ Montpellier 2 Lab LIRMM UMR 5506 F-34392 Montpellier 05 France

We propose an efficient lossless compression scheme for still images based on arithmetic coding. The scheme presents a novel adaptive arithmetic coding that updates the probabilities of pixels only after detecting the last occurrence of each pixel and then removes the redundancy from the original image effectively. The proposed approach has interestingly low computational complexity. In addition, unlike other statistical coding techniques, arithmetic coding in the proposed scheme is not solely dependent on the pixel probability distribution but also on the image block sorting. The proposed method is compared to both static and adaptive order-0 models while taking into account compression ratios and processing time. Experimental results, based on a set of 100 gray-level images, demonstrate that the proposed scheme gives mean compression ratios that are 5.5% higher than those by the conventional arithmetic encoders as well as significantly faster than the order-0 adaptive arithmetic coding. (C) 2010 SPIE and IS&T. [DOI: 10.1117/1.3435341]

关键词： Image compression Computer programming Image processing Binary data algorithm development Biotechnology Data compression Data modeling Data storage Telecommunications

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Formulation and validation of simulated data for the Atmospheric Infrared Sounder (AIRS)

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IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING 2003年第2期41卷 314-329页

作者： Fishbein, E Farmer, CB Granger, SL Gregorich, DT Gunson, MR Hannon, SE Hofstadter, MD Lee, SY Leroy, SS Strow, LL CALTECH Jet Prop Lab Pasadena CA 91109 USA Univ Maryland Baltimore Cty Dept Phys Baltimore MD 21205 USA

Models for synthesizing radiance measurements by the Atmospheric Infrared Sounder (AIRS) are described. Synthetic radiances have been generated for developing and testing data processing algorithms. The radiances are calculated from geophysical states derived from weather forecasts and climatology using the AIRS rapid transmission algorithm. The data contain horizontal variability at the spatial resolution of AIRS from the surface and cloud fields. This is needed to test retrieval algorithms under partially cloudy conditions. The surface variability is added using vegetation and International Geosphere Biosphere Programme surface type maps, while cloud variability is added randomly. The radiances are spectrally averaged to create High Resolution Infrared Sounder (HIRS) data, and this is compared with actual HIRS2 data on the NOAA 14 satellite. The simulated data underrepresent high-altitude equatorial cirrus clouds and have too much local variability. They agree in the mean to within 1-4 K, and global standard deviation agrees to better than 2 K. Simulated data have been a valuable tool for developing retrieval algorithms and studying error characteristics and will continue to be so after launch.

关键词： algorithm development atmospheric retrieval cloud scene modeling data simulation High Resolution Infrared Sounder (HIRS) satellite remote sensing

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HYBRID OPTOELECTRONIC ANALOG-TO-DIGITAL CONVERSION SYSTEM

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OPTICAL ENGINEERING 1983年第5期22卷 619-632页

作者： KIM, JC LIU, HK UNIV ALABAMA DEPT ELECT ENGN UNIVERSITY AL 35486 USA

A new hybrid, direct, real-time, and parallel analog-to-digital (A/D) conversion system has been theoretically and experimentally investigated. Basically this system consists of an A/D conversion screen, a photosensor panel, a comparator, and a coder. For the purpose of designing an A/D conversion screen, various quantizer characteristics and the minimization of the mean-square distortion are briefly described. Based on the quantizer characteristics, the design algorithms of the A/D conversion screen are developed. It is found that charge-coupled device (CCD), charge-injection device (CID), and metal oxide semiconductor (MOS) photodiode image sensor arrays can be used for the large-area hybrid A/D conversion system, and photodiode or photocell arrays can be applied for a single-pixel A/D conversion system. An error analysis shows that the conversion errors result from the discrepancy between the fabricated and designed transmittance function of the screen cells and the nonuniform characteristics of the photosensors. Also, this system is theoretically compared with existing electronic A/D conver-sion systems. To show the feasibility of this system, a single-pixel 16-level A/D conversion system using a single-cell 16-level A/D conver-sion screen, a photosensor panel of 16 photocells, and accessory elec-tronic circuits is designed, constructed, and experimented with input op-tical signals. The experimental results proved that this system can be used for achieving A/D conversion of both coherent or incoherent and monochromatic or polychromatic optical signals. The system can be potentially applied for the interface at the optical input of a digital computer for real-time optical data processing, picture coding, and optical telemetry.

关键词： Optoelectronics algorithm development Charge-coupled devices Error analysis Photodiodes CCD image sensors Distortion Metals Oxides Semiconductors

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Feature extraction and clustering for the computer-aided reconstruction of strip-cut shredded documents

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JOURNAL OF ELECTRONIC IMAGING 2008年第1期17卷

作者： Ukovich, Anna Ramponi, Giovanni Univ Trieste Dipartimento Elettrotecn Elett & Informat I-34127 Trieste Italy

We propose a solution for the computer-aided reconstruction of strip-cut shredded documents. First of all, the visual content of the strips is automatically extracted and represented by a number of numerical features. Usually, the pieces of different pages have been mixed. A grouping of the strips belonging to a same page is thus realized by means of a clustering operator, to ease the successive matching performed by a human operator with the help of a computer. (c) 2008 SPIE and IS&T.

关键词： Feature extraction Visualization Reconstruction algorithms Image processing Hough transforms Image retrieval Scanners algorithm development Chromium Surface plasmons

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Volume estimates of trees with complex architecture from terrestrial laser scanning

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JOURNAL OF APPLIED REMOTE SENSING 2008年第1期2卷

作者： Lefsky, Michael McHale, Melissa Colorado State Univ Dept Nat Resources Ctr Ecol Anal Lidar Ft Collins CO 80523 USA Arizona State Univ Global Inst Sustainabil Tempe AZ 85287 USA

Research on urban forest carbon storage requires new allometric equations that relate easily measured aspects of tree form to total tree volume. Existing methods for creating these equations are time consuming and can require destructive sampling. In this study we used a terrestrial lidar sensor;data produced by this system consists of the three-dimensional locations of points that lay on object surfaces (in this case the trunk, branches, twigs, etc.). The challenge in calculating tree volume was the aggregation of these individual points into objects whose dimensions could be reliably estimated. We converted the lidar observations into 3-dimensional voxels, identified narrow (< 20 cm) sections along the stems, and merged sections on the basis of their connectivity. The distribution of returns from small branches was analyzed on the basis of branch size and the sampling pattern of the sensor. Two hundred and fifty measurements of stem diameter were made on 14 trees of two species using both lidar and field measurements;the estimates were highly correlated (r(2) > 98%) and unbiased. The processing algorithm was applied to lidar data from 179 trees of 11 species;the accuracy of results was dependant on tree volume, species and tree form.

关键词： terrestrial lidar urban trees allometric relationships volume equations algorithm development

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Qualitative analysis of two reconstruction techniques and their application in dentistry

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JOURNAL OF ELECTRONIC IMAGING 2000年第4期9卷 385-393页

作者： Nonato, LG Minghim, R Shimabukuro, MH Univ Sao Paulo Inst Ciencias Matemat & Comp BR-13560970 Sao Carlos SP Brazil UNESP Pres Prudente SP Brazil

Although visualization in the field of dentistry has some of the same requirements as the medicine field, the differences in goal demand specific approaches. This paper reports on the implementation of two fundamentally different approaches to reconstruction of structures from planar cross sections and their application to dentistry data. One of the approaches was an implementation of a distance-based sampling technique, and the other is a new algorithm, based on the Delaunay triangulation. Both were tested using contour data of teeth and the results are compared here in the light of the target applications, which are teaching and training dentistry, as well as simulation of dental procedures and illnesses, Widely mentioned problems encountered in local reconstruction methods such as marching cubes for these cases ate clearly illustrated in this paper, and a very satisfactory alternative is given. (C) 2000 SPIE and IS&T. [S1017-9909(00)01504-X].

关键词： Reconstruction algorithms Dentistry Teeth Visualization 3D modeling Data modeling Visual process modeling algorithm development Computer simulations Medicine

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Evaluation of algorithms for lossless compression of continuous-tone images

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JOURNAL OF ELECTRONIC IMAGING 2002年第1期11卷 75-86页

作者： Savakis, AE Rochester Inst Technol Dept Comp Engn Rochester NY 14623 USA

Lossless image compression algorithms for continuous-tone images have received a great deal of attention in recent years. However, reports on benchmarking their performance have been limited. In this paper, we present a comparative study of the following algorithms: UNIX compress, gzip, LZW, Group 3, Group 4, JBIG, old lossless JPEG, JPEG-LS based on LOCO, CALIC, FELICS, S + P transform, and PNG. The test images consist of two sets of eight bits/pixel continuous-tone images: one set contains nine pictorial images, and another set contains eight document images, obtained from the standard set of CCITT images that were scanned and printed using eight bits/pixel at 200 dpi. In cases where the algorithm under consideration could only be applied to binary data, the bitplanes of the gray scale image were decomposed, with and without Gray encoding, and the compression was applied to individual bit planes. The results show that the best compression is obtained using the CALIC and JPEG-LS algorithms. (C) 2002 SPIE and IST.

关键词： Image compression Computer programming Image processing algorithm development Data modeling Image quality standards Binary data Error analysis Bridges Photonic integrated circuits

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Comparison of adaptive linear interpolation and conventional linear interpolation for digital radiography systems

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JOURNAL OF ELECTRONIC IMAGING 2000年第1期9卷 22-31页

作者： Xu, F Liu, H Wang, G Alford, BA Univ Virginia Charlottesville VA 22908 USA

Some large field digital radiography systems are currently under development using multiple detectors. These small size two dimension detectors are abutted together to cover a large field Physical gaps existing between adjacent defectors produce seams between the resultant subimages. In this paper, an adaptive linear interpolation algorithm was introduced for estimating missing information at the seams and was compared with conventional linear interpolation and with nonlinear interpolation. The effectiveness of the algorithms was evaluated for relative/absolute errors. Phantom images were acquired using prototype digital radiography systems. Seams with width ranging from two pixel to six pixel were introduced and adaptive linear interpolation algorithms were applied to estimate missing information at the seams. Quantitatively, the adaptive interpolation offers at least equivalent or less error than that of the linear interpolation algorithm. The experimental results prove that there is a significant difference between two algorithms for tested radiographic images. The comparison results also show that the adaptive interpolation offers better performance than nonlinear interpolation. When developing large field digital radiography imaging systems, gaps between adjacent detectors should be minimized. For narrow seams, the adaptive linear interpolation algorithm is a practical solution because of its simplicity and effectiveness. (C) 2000 SPIE and IS&T. [S1017-9909(00)00201-4].

关键词： Radiography Error analysis Sensors Detection and tracking algorithms Bone Charge-coupled devices Prototyping algorithm development Imaging systems Reconstruction algorithms

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Split and merge codebook design algorithms for image compression

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JOURNAL OF ELECTRONIC IMAGING 2000年第4期9卷 509-520页

作者： Karayiannis, NB Liu, ZY Univ Houston Dept Elect & Comp Engn Houston TX 77204 USA Toshiba Int Corp Houston TX 77041 USA

This paper introduces two new codebook design algorithms for image data compression applications. The proposed algorithms design codebooks by splitting and merging the prototypes of the training vectors, which play the role of code-vectors in the encoding/decoding process. The split-1 (S1) algorithm begins with a codebook containing a single prototype and designs a codebook of the desired size by splitting one prototype at each iteration. The split-1-merge-2 (S1M2) algorithm begins with a codebook of the desired size and improves its quality in an iterative fashion by splitting one prototype and merging two prototypes at each iteration. The proposed algorithms are used to design codebooks for image data compression based on vector quantization. The experimental results indicate that the proposed algorithms are strong competitors to the popular Linde-Buzo-Gray algorithm in terms of their computational requirements and the quality of the designed codebooks. (C) 2000 SPIE and IS&T. [S1017-9909(00)00204-X].

关键词： Prototyping Image compression Quantization Reconstruction algorithms Image quality Image filtering algorithm development Digital imaging Computer programming Optical filters

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Chaotic gray-level image transformation

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JOURNAL OF ELECTRONIC IMAGING 2005年第4期14卷

作者： Belkhouche, F Gokcen, I Qidwai, U Tulane Univ Dept Elect Engn & Comp Sci New Orleans LA 70118 USA Gen Elect Global Res Ctr Niskayuna NY USA

We deal with the applications of a class of nonlinear dynamic systems to image transformation and encoding whereby the nonlinear system presents a chaotic or hyperchaotic attractor. Several ways are possible to encode or transform the image using chaos. We develop algorithms for image encoding based on the permutation of the pixel value, position, or both. This approach enables the fast decorrelation of relations among pixels in the initial image in a random-like fashion. We illustrate the use of 1-D, 2-D, and 3-D maps for this purpose. We also use chaotic dynamical systems with a single or two outputs. A discussion of the sensitivity of the algorithms to the keys is followed by the illustration of the algorithms using example images. (c) 2005 SPIE and IS&T.

关键词： Computer programming Complex systems Image compression Dynamical systems Image encryption algorithm development Chaos Diffusion Fractal analysis Nonlinear dynamics

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