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Showing papers on "Subpixel rendering published in 1997"


Patent
20 Mar 1997
TL;DR: In this paper, a system and method for rapid collection of data points and construction of a computer model based on a multi-resolution mesh to describe the surface contours and color of an object is presented.
Abstract: System and method for rapid collection of data points and construction of a computer model based on a multi-resolution mesh to describe the surface contours and color of an object (101). The system collects data by projecting shapes of light (121-125) against the object (101) and collecting (from a position of triangulation relative to the light projector) images of the light as it reflects from the object. The system and method are comprised of a multiple laser stripe generation process to project a number of light shapes against the object, the collection of one or more reflected laser stripes in a single image of an images collector (120) to gather sufficient information to reproduce points on the surface of the object. The system compresses the data associated with collected points, which allows for accurate values for the contours of the object to subpixel accuracy. A multi-resolution analysis, which maintains more points to resolve fine details and removes points to further smooth regions of the objects, leads to significant compression. The adaptive mesh, consisting of the connection of polygonal finite elements, is automatically generated by the system and is comprised to create multi-resolution meshes at different tolerances.

189 citations


Journal ArticleDOI
TL;DR: An alignment routine developed to register an image of a fixed object containing a global offset error, rotation error, and magnification error relative to a second image, which is a fast, robust, and automatic alignment algorithm.
Abstract: A number of digital imaging techniques in medicine require the combination of multiple images. Using these techniques, it is essential that the images be adequately aligned and registered prior to addition, subtraction, or any other combination of the images. This paper describes an alignment routine developed to register an image of a fixed object containing a global offset error, rotation error, and magnification error relative to a second image. The described routine uses sparsely sampled regional correlation in a novel way to reduce computation time and avoid the use of markers and human interaction. The result is a fast, robust, and automatic alignment algorithm, with accuracy better than about 0.2 pixel in a test with clinical computed radiography images.

154 citations


Patent
17 Jan 1997
TL;DR: A multicolor optical image-generating device comprised of an array of grating light valves (GLVs) organized to form light-modulating pixel units for spatially modulating incident rays of light is described in this paper.
Abstract: A multicolor optical image-generating device comprised of an array of grating light valves (GLVs) organized to form light-modulating pixel units for spatially modulating incident rays of light. The pixel units are comprised of three subpixel components each including a plurality of elongated, equally spaced apart reflective grating elements arranged parallel to each other with their light-reflective surfaces also parallel to each other. Each subpixel component includes means for supporting the grating elements in relation to one another, and means for moving alternate elements relative to the other elements and between a first configuration wherein the component acts to reflect incident rays of light as a plane mirror, and a second configuration wherein the component diffracts the incident rays of light as they are reflected from the grating elements. The three subpixel components of each pixel unit are designed such that when red, green and blue light sources are trained on the array, colored light diffracted by particular subpixel components operating in the second configuration will be directed through a viewing aperture, and light simply reflected from particular subpixel components operating in the first configuration will not be directed through the viewing aperture.

107 citations


Patent
15 Oct 1997
TL;DR: In this article, a pixel is partitioned into subpixel locations from which sample points are selected, and a fragment of the image is determined to be visible at at least one of the sample points.
Abstract: A method and an apparatus reduces aliasing artifacts in images defined by pixels. A pixel is partitioned into subpixel locations from which sample points are selected. A fragment of the image is determined to be visible at at least one of the sample points. A fragment value associated with that fragment is stored. Each sample point at which the fragment is visible is linked to the stored fragment value. A color of the pixel is computed from the stored fragment values to reduce the aliasing artifacts in the image.

104 citations


Patent
23 Sep 1997
TL;DR: In this article, a video graphics processor walks the first and second edges based on calculations involving a decision corner and an error turn, i.e., whether the walking should be in the major direction or the minor direction.
Abstract: A method and apparatus for providing video graphics processing that includes anti-aliasing begins when a video graphics processor receives vertex parameters of an object-element and walks a first edge of the object element and a second edge of the object element. The video graphics processor walks the first and second edges based on calculations involving a decision corner and an error turn. The calculations indicate which direction to walk on a pixel by pixel basis, i.e., whether the walking should be in the major direction or the minor direction. The calculations also identify pixels that contain fragment pixel information, i.e., the pixels along the edges of the object element. For each fragment pixel, subpixel masks are created for each object element that is present in the fragmented pixel. From the subpixel masks, subpixel sequences are determined, which are used to produce pixel information of the fragment pixel.

103 citations


Journal ArticleDOI
TL;DR: The authors have successfully parameterized subpixel scale heterogeneity effects for the estimation of vegetation index, by modeling the variances and covariance terms with the pixel scale values.
Abstract: The land surface exhibits heterogeneity across a range of spatial scales. Remote sensors provide integrated information at the pixel scale, however, there is important spatial variability at scales smaller than the scale of the sensor. On the other hand, large scale models that use remotely sensed data do not require them at the same spatial resolution at which remote sensors are required to operate. In this paper, a framework for testing aggregation-disaggregation properties of remote sensing algorithms is presented. The proposed framework provides a systematic approach for parameterizing the land surface heterogeneity effects. For the estimation of the pixel scale response, the lumped response should be modified by the variance and covariance terms. This representation of land surface heterogeneity could lead to substantial savings in remote sensing data storage and management. Using simulated land and vegetation scenarios, the authors have successfully parameterized subpixel scale heterogeneity effects for the estimation of vegetation index, by modeling the variances and covariance terms with the pixel scale values.

94 citations


Journal ArticleDOI
TL;DR: The subpixel interpolation technique is demonstrated to be far better than traditional methods when multiple or entire curves are present in a very small neighborhood, and to avoid the propagation of information across singularities.

87 citations


Proceedings ArticleDOI
Stephanie Winner1, Michael W. Kelley, Brent Pease1, Bill Rivard1, Alex Yen 
03 Aug 1997
TL;DR: Algorithms for accelerating antialiasing in 3D graphics through low-cost custom hardware through a multiple-pass algorithm to perform front-to-back hidden surface removal and shading are described.
Abstract: one pass per subpixel sample) through the hardware rendering pipeline. The resulting image is very high quality, but the performance degrades in proportion to the number of subpixel samples used by the filter function. This paper describes algorithms for accelerating antialiasing in 3D graphics through low-cost custom hardware. The rendering architecture employs a multiple-pass algorithm to perform front-to-back hidden surface removal and shading. Coverage mask evaluation is used to composite objects in 3D. The key advantage of this approach is that antialiasing requires no additional memory and decreases rendering performance by only 30-40% for typical images. The system is image partition based and is scalable to satisfy a wide range of performance and cost constraints. An A-buffer implementation does not require several passes of the object data, but does require sorting objects by depth before compositing them. The amount of memory required to store the sorted layers is limited to the number of subpixel samples, but it is significant since the color, opacity and mask data are needed for each layer. The compositing operation uses a blending function which is based on three possible subpixel coverage components and is more computationally intensive than the accumulation buffer blending function. The difficulty of implementing the A-buffer algorithm in hardware is described by Molnar [12]. CR

73 citations


Patent
16 Jun 1997
TL;DR: In this paper, a method for combining foreground objects defined by a mask value and shading value, with a background image defining by a shade value, using high resolution edge information derived from low resolution grey image representations, is presented.
Abstract: A method for combining foreground objects defined by a mask value and shade value, with a background image defined by a shade value, using high resolution edge information derived from low resolution grey image representations. By treating the object edge pixels in a high resolution grey model, characteristics of an edge represented by an edge pixel can be approximated by reference to surrounding grey elements. Movement of the edge can be approximated by changing the mask values in the high resolution grey model. Changes in the overall grey level of the pixel resulting from the mask changes cause the impression of edge movement in the low resolution edge.

60 citations


Journal ArticleDOI
TL;DR: In this article, the authors measured the X-ray detection efficiency of a charge-coupled device (CCD) with subpixel resolution using a metal mesh placed just in front of the CCD.
Abstract: We report the use of a new technique to measure the X-ray detection efficiency of a charge-coupled device (CCD) with subpixel resolution. The new technique makes use of a parallel X-ray beam and metal mesh placed just in front of the CCD. The CCD camera we used is a conventional system using the TC213 (Texas Instrument Japan (TIJ)) whose pixel size is 12 µ m ×12 µ m with one million pixels. The mesh has 4 µm diameter holes spaced at 12 µm intervals. We produced an efficiency map within a typical pixel showing the gate structure in detail: a virtual gate, a clock gate and an antiblooming gate. The gate structure we measured is consistent with the manufacturer's design value. By selecting single pixel events, we detected a pixel boundary. Additional plans for application will also be discussed.

51 citations


Patent
23 Sep 1997
TL;DR: In this article, a video graphics processor walks the first and second edges based on calculations involving a decision corner and an error turn, i.e., whether the walking should be in the major direction or the minor direction.
Abstract: A method and apparatus for providing video graphics processing that includes anti-aliasing begins when a video graphics processor receives vertex parameters of an object-element and walks a first edge of the object element and a second edge of the object element. The video graphics processor walks the first and second edges based on calculations involving a decision corner and an error turn. The calculations indicate which direction to walk on a pixel by pixel basis, i.e., whether the walking should be in the major direction or the minor direction. The calculations also identify pixels that contain fragment pixel information, i.e., the pixels along the edges of the object element. For each fragment pixel, subpixel masks are created for each object element that is present in the fragmented pixel. From the subpixel masks, subpixel sequences are determined, which are used to produce pixel information of the fragment pixel.

Patent
15 Dec 1997
TL;DR: In this article, an autostereoscopic method and a device for the three-dimensional representation of information according to a barrier-, lenticular-, prismatic mask-, or similar method using flat-panel displays (liquid crystal-, plasma-, electroluminescent-or other displays) for use in computer and video technology, games and advertising, medical engineering, virtual reality applications, and other fields.
Abstract: The invention relates to an autostereoscopic method and a device for the three-dimensional representation of information according to a barrier-, lenticular-, prismatic mask-, or similar method using flat-panel displays (liquid crystal-, plasma-, electroluminescent- or other displays) for use in the computer and video technology, games and advertising, medical engineering, virtual reality applications, and other fields. According to the invention, the image points are proportionally tracked to lateral movement of the observer by shifting, for each colored subpixel, of the intensities of the colored subpixels to horizontally adjacent colored subpixels. The method can be used with known devices. It becomes especially useful when, for each image point, n+1 adjacent colored subpixels are addressed. Observers moving sideways continue to see the image in practically consistently high quality.

Journal ArticleDOI
TL;DR: In this paper, a stereoscopic electronic speckle photography system is presented that detects 3-D displacement fields or object shape with subpixel accuracy, and data are stored, results are presented, and calculations are performed in a PC computer.
Abstract: A stereoscopic electronic speckle photography system is presented that detects 3-D displacement fields or object shape with subpixel accuracy. The system is all electronic, and data are stored, results are presented, and calculations are performed in a PC computer. The expected standard deviation of measurements of small deformations are about 0.001% of the object size for in-plane measurements and about 0.006% of the object size for the out-of-plane component, when white light speckles are used.

Journal ArticleDOI
TL;DR: In this article, the accuracy of centroid algorithms in 1D, 2D and 3D can be investigated and three factors that can influence the method's accuracy have been investigated: systematic error of the algorithm, influence of photon noise and the influence of perturbations such as scanning nonlinearity.
Abstract: The accuracy with which centroid algorithms in 1D, 2D and 3D can estimate an object's position has been investigated. Three factors that can influence the method's accuracy have been investigated: systematic error of the algorithm, influence of photon noise and the influence of perturbations such as scanning nonlinearity. The variation of the accuracy with parameters that are relevant for confocal microscopy, such as object diameter and photon noise/pixel, has been considered. Theory and simulations presented show that the variation of the accuracy with respect to such parameters can differ drastically between the 1D, 2D and 3D cases. Experiments performed using microspheres show that the magnitudes of the three types of error can be approximately the same under normal operating conditions and that it is therefore necessary to take all three into account when assessing the total error.

Patent
24 Jun 1997
TL;DR: In this article, a multi-color pixel for a twisted nematic liquid crystal display including red, green, and blue subpixels was proposed, where each subpixel includes a pair of substrates, a pairs of polarizers, opposing electrodes, and a color personalized retardation film which compensates for the different wavelength of each color.
Abstract: A multi-colored pixel for a twisted nematic liquid crystal display including red, green, and blue subpixels, wherein each subpixel includes a pair of substrates, a pair of polarizers, opposing electrodes, and a color personalized retardation film which compensates for the different wavelength of each color. The personalized retardation films of the different color subpixels results in elimination of the multi-gap approach and substantially eliminates the problem of different color leakages at different viewing angles, including normal. Also, one polymer based element, preferably a polyimide, functions as both a color filter and a retardation film in certain embodiments of this invention.

Book ChapterDOI
15 Sep 1997
TL;DR: The implementation of the tensor approach to dense displacement vector fields will be introduced together with an error analysis and the performance of the technique will be proved with test sequences as well as with real scientific applications.
Abstract: Using the 3-dimensional structure tensor, dense displacement vector fields (DVF) can be computed with subpixel accuracy. The approach is based on the detection of linear symmetries and the corresponding orientation angle within a local spatio-temporal neighborhood. The proposed technique is well suited to be applied within a multiresolution framework in order to avoid corresponence problem errors. In this paper the implementation of the tensor approach will be introduced together with an error analysis. The performance of the technique will be proved with test sequences as well as with real scientific applications.

Journal Article
TL;DR: In this article, the authors compared machine-vision and neural networks for detecting woody vegetation in satellite imagery. And they found that the neural network approach outperformed the machine vision approach.
Abstract: Small strips or patches of woody vegetation, typical landscape elements in many farming areas, are frequently not detected by standard computer-assisted classification of digital satellite imagery because such landscape elements are smaller than the pixel size and are mixed with other classes. This study essentially compares two artificial intelligence approaches-machine-vision and neural-network methods-developed to improve classification accuracy for this mixed pixel problem. Simulated multispectral and panchromatic SPOT HRV imagery of lowland Britain was used to test both methods. Compared to standard supervised multispectral classification, both methods yield significant improvements in detecting subpixel woody vegetation. In general, the machine-vision approach outperformed the neural-network approach. However, because each method generated different types of misclassifications, a classification map representing only the woody vegetation found by both methods provided the results with the least amount of overall error.

Patent
15 Dec 1997
TL;DR: In this paper, the addressing circuitry includes spatial and/or temporal dither circuits for addressing separately addressable subpixels with different spatial dither signals in separate subframes, and switches each pixel or subpixel between different grey states corresponding to different transmission levels.
Abstract: A ferroelectric liquid crystal display comprises an addressable matrix of pixels, and addressing circuitry for selectively addressing each pixel in order to vary the transmission level of the pixel relative to the transmission levels of the other pixels. The addressing circuitry includes spatial and/or temporal dither circuits for addressing separately addressable subpixels with different spatial dither signals and/or for addressing each pixel or subpixel with different temporal dither signals in separate subframes. In addition to such spatial and/or temporal dither, the addressing circuitry switches each pixel or subpixel between different grey states corresponding to different transmission levels, with at least two of the bits of spatial or temporal dither being switchable between more than two different grey states and at least one bit being switchable between a lesser number of different grey states than the or each other bit, so that a plurality of different overall transmission levels are achievable by different combinations of spatial and/or temporal dither and such grey states. This allows a larger number of substantially linearly spaced or suitably weighted grey levels to be produced than has previously been possible without giving rise to unacceptable complications.

Journal ArticleDOI
TL;DR: In this paper, a method for improving the performance of subpixel edge localization (EL) techniques through compensation of the systematic portion of the localization error is proposed, based on the estimation of the EL characteristic through statistical analysis of a test image.
Abstract: We propose and analyze a method for improving the performance of subpixel edge localization (EL) techniques through compensation of the systematic portion of the localization error. The method is based on the estimation of the EL characteristic through statistical analysis of a test image and is independent of the EL technique in use.

Proceedings ArticleDOI
07 Sep 1997
TL;DR: This paper proposes a method which is based on a camera model that incorporates lens distortion, and involves a nonlinear minimization technique which can be performed using multiple views of a single 2D object and subpixel feature extraction.
Abstract: An important task in most 3D vision systems is camera calibration. Many camera models, numerical methods and experimental set-ups have been proposed in the literature to solve the calibration problem. We have analysed and tried many methods, and we conclude that the main problems lie in the choice of the numerical methods and on the calibration object. We propose in this paper a method which is based on a camera model that incorporates lens distortion, and involves a nonlinear minimization technique which can be performed using multiple views of a single 2D object and subpixel feature extraction. We present an application for which only a 2D calibration object can be used.

Patent
23 Sep 1997
TL;DR: In this article, a video graphics processor walks the first and second edges based on calculations involving a decision corner and an error term, i.e., whether the walking should be in the major direction or the minor direction.
Abstract: A method and apparatus for providing video graphics processing that includes anti-aliasing begins when a video graphics processor receives vertex parameters of an object-element and walks a first edge of the object element and a second edge of the object element. The video graphics processor walks the first and second edges based on calculations involving a decision corner and an error term. The calculations indicate which direction to walk on a pixel by pixel basis, i.e., whether the walking should be in the major direction or the minor direction. The calculations also identify pixels that contain fragment pixel information, i.e., the pixels along the edges of the object element. For each fragment pixel, subpixel masks are created for each object element that is present in the fragmented pixel. From the subpixel masks, subpixel sequences are determined, which are used to produce pixel information of the fragment pixel.

Journal ArticleDOI
TL;DR: This work suggests to use manhole covers as a specific type of circular landmarks which frequently occur in urban environments and introduces a model-based approach for localizing these features with high subpixel precision based on a parametric intensity model.
Abstract: The photogrammetric exploitation of aerial images essentially requires the accurate reconstruction of the imaging geometry. This especially includes the determination of the orientation of the camera. Usually, the orientation parameters are determined by spatial resection, knowing the exact coordinates of control points on the ground and in the image. The reliability and accuracy of this registration task strongly depend on the selection of suitable landmarks as well as on the precision obtained for landmark localization. In this contribution, we consider the problem of automatic landmark extraction for the purpose of aerial image registration. We suggest to use manhole covers as a specific type of circular landmarks which frequently occur in urban environments and we introduce a model-based approach for localizing these features with high subpixel precision. Our approach is based on a parametric intensity model. Localization of the landmarks is done by directly fitting this model to the observed image intensities. Since we have an explicit description of the landmark it is possible to verify the result by exploiting the estimated parameters. We also address the problem of landmark detection which can greatly be supported by template matching. The template used is a prototype model which is generated from representative examples during a training phase. The training scheme also provides initial values for the fitting procedure as well as thresholds for the final verification step. The full approach has been tested on synthetic as well as on real image data.

Patent
15 Dec 1997
TL;DR: In this paper, an autostereoscopic method and a device for the three-dimensional representation of information according to a barrier-, lenticular-, prismatic masking-or similar method by means of flat-panel displays (liquid crystal, plasma, electroluminescent or other displays), for use in computer and video technology, games and advertisements, medical technology, virtual reality applications and other areas.
Abstract: The invention relates to an autostereoscopic method and a device for the three-dimensional representation of information according to a barrier-, lenticular-, prismatic masking- or similar method by means of flat-panel displays (liquid crystal, plasma, electroluminescent or other displays), for use in computer and video technology, games and advertisements, medical technology, virtual reality applications and other areas. According to the invention, the image points are proportionally displaced to follow the lateral movement of an observer by shifting, for each coloured subpixel, the intensity of the coloured subpixels to horizontally adjacent coloured subpixels. This method can be used with known devices. It becomes especially useful wehn, for each image point, n+1 adjacent coloured subpixels are triggered. Observers moving sideways continue to see the picture in almost consistently high quality.

Journal ArticleDOI
TL;DR: In this article, a method is proposed for recovering a binary image from multilevel pixel values, which are modelled by a convolution of the true scene with a blurring kernel, together with additive noise.
Abstract: Recovery of object boundaries to subpixel accuracy is possible from digital images if su cient assumptions can be made. Subpixel restoration is of most relevance if an object is at the limit of resolution of a sensor, either being only a few pixels in size or having ne structure. A method is proposed for recovering a binary image from multilevel pixel values, which are modelled by a convolution of the true scene with a blurring kernel, together with additive noise. Small objects, such as immunogold-labelled particles in electron micrographs, are parameterised using Fourier descriptors, and a network of splines is used to parameterise the lament structure of fungal hyphae.

Proceedings ArticleDOI
10 Jan 1997
TL;DR: In this article, a Bayesian multiframe enhancement algorithm is presented to compute an HRVS using the spatial information present within each frame as well as the temporal information present due to object motion between frames.
Abstract: Multiframe resolution enhancement algorithms are used to estimate a high-resolution video still (HRVS) from several low-resolution frames, provided that objects within the image sequence move with subpixel increments. A Bayesian multiframe enhancement algorithm is presented to compute an HRVS using the spatial information present within each frame as well as the temporal information present due to object motion between frames. However, the required subpixel- resolution motion vectors must be estimated from low- resolution and noisy video frames, resulting in an inaccurate motion field which can adversely impact the quality of the enhanced image. Several subpixel motion estimation techniques are incorporated into the Bayesian multiframe enhancement algorithm to determine their efficacy in the presence of global data transformations between frames and independent object motion. Visual and quantitative comparisons of the resulting high-resolution video stills computed from two video frames and the corresponding estimated motion fields show that the eight- parameter projective motion model is appropriate for global scene changes, while block matching and Horn-Schunck optical flow estimation each have their own advantages and disadvantages when used to estimate independent object motion.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Journal ArticleDOI
TL;DR: A complete system for the recognition and localization of a three-dimensional (3-D) model from a sequence of monocular images with known motion, using a purely 3-D approach, which yields a robust recognition and precise localization of the model in the scene.
Abstract: In this paper, we present a complete system for the recognition and localization of a three-dimensional (3-D) model from a sequence of monocular images with known motion. The originality of this system is twofold. First, it uses a purely 3-D approach, starting from the 3-D reconstruction of the scene and ending by the 3-D matching of the model. Second, unlike most monocular systems, we do not use token tracking to match successive images. Rather, subpixel contour matching is used to recover more precisely complete 3-D contours. In contrast with the token tracking approaches, which yield a representation of the 3-D scene based on disconnected segments or points, this approach provides us with a denser and higher level representation of the scene. The reconstructed contours are fused along successive images using a simple result derived from the Kalman filter theory. The fusion process increases the localization precision and the robustness of the 3-D reconstruction. Finally, corners are extracted from the 3-D contours. They are used to generate hypotheses of the model position, using a hypothesize-and-verify algorithm that is described in detail. This algorithm yields a robust recognition and precise localization of the model in the scene. Results are presented on infrared image sequences with different resolutions, demonstrating the precision of the localization as well as the robustness and the low computational complexity of the algorithms.

Proceedings ArticleDOI
26 Oct 1997
TL;DR: Simulations compare the high-resolution video stills which result from using the subpixel motion vectors calculated by block matching and the proposed Bayesian motion estimation technique.
Abstract: Multiframe resolution enhancement methods are used to estimate a high-resolution video still (HRVS) from several low-resolution image sequence frames, provided that objects within the video sequence move with subpixel increments. Estimating accurate subpixel-resolution motion vectors is a challenging, albeit critically important component of super-resolution enhancement algorithms. A Bayesian motion estimation technique is proposed which models the motion field with a discontinuity-preserving prior. The method is related to Horn-Schunck (1981) optical flow estimation, except that the discontinuity-preserving prior can allow abrupt changes within the motion field without the use of line processes. Simulations compare the high-resolution video stills which result from using the subpixel motion vectors calculated by block matching and the proposed Bayesian motion estimation technique.

Proceedings ArticleDOI
TL;DR: Experimental evaluation shows that it is important to use substripe estimation and incorporate lens distortion in the projector model, and to have a balance in the accuracy of all components in the structured light system.
Abstract: This paper discusses a method for obtaining accurate 3D measurements using a temporally encoded structured light system. An objective of the work was to have a balance in the accuracy of all components in the system. This was achieved by including lens distortion in the modes for both the camera and projector which comprise the structured light system. In addition, substripe estimation was used to estimate projector stripe values as a complement to subpixel estimators used for locating image features. Experimental evaluation shows that it is important to use substripe estimation and incorporate lens distortion in the projector model.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Journal ArticleDOI
TL;DR: This paper applies the new approach to stereo disparity estimation based on sliding blocks to standard stereoscopic images and demonstrates up to 2.4 dB reduction of disparity-compensated prediction error over the traditional sliding-block method.
Abstract: In a typical disparity (or motion) estimation algorithm developed for interimage prediction, an interpolation of intensities is applied to one of the two images used. Therefore, nonfiltered intensities of the image being predicted are compared with low-pass-filtered intensities of the other image of the stereo pair. Consequently, noise and detail suppression in the two images are unequal. In this paper we propose to apply the same (balanced) filtering to both images. In addition to image smoothing that helps avoid unreliable intensity matches, a low-pass filter is used to carry out intensity interpolation at the same time; the computation of subpixel attributes is consistent with low-pass filtering of both images unlike arbitrary linear or cubic interpolation applied to one image only. The proposed approach lends itself naturally to a multiresolution implementation, We apply the new approach to stereo disparity estimation based on sliding blocks. Using synthetic and natural data we experimentally compare the new approach with the traditional sliding-block method. For standard stereoscopic images we demonstrate up to 2.4 dB reduction of disparity-compensated prediction error over the traditional sliding-block method.

Patent
16 Sep 1997
TL;DR: A liquid crystal display (LCD) panel construction for producing color images for viewing by a viewer is described in this paper, where an illumination panel for producing light including spectral components with wavelengths in a visible band of the electromagenetic spectrum is constructed.
Abstract: A liquid crystal display (LCD) panel construction for producing color images for viewing by a viewer The LCD panel construction comprises: an illumination panel for producing light including spectral components with wavelengths in a visible band of the electromagenetic spectrum; a plurality of pixel regions within a predefined image display area, wherein each pixel region has a plurality of subpixel region and each said subpixel region within each pixel region has a light transmission portion and a light blocking portion, and each light transmission portion and light blocking portion has a frontside disposed in the direction in the viewer and a backside in the direction of the illumination panel The illumination panel illuminates the plurality of pixel regions from the backside thereof so that a color image is formed the said plurality of pixel regions for viewing A pattern of broad-band reflector material is disposed in spatial registration with the backside of the light blocking portions of the subpixel regions, for reflecting produced light at structures associated with the light blocking portions of the subpixels, thereby recycling produced light for use in illuminating said plurality of pixel regions A pattern of broad-band absorption material is also disposed in spatial registration with the frontside of the light blocking portions of the subpixel regions, for absorbing ambient light incident upon structures associated with the light blocking portions of the subpixels, thereby reducing glare at the surface of the LCD panel due to ambient light incident thereon