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Showing papers on "Channel (digital image) published in 1991"


Patent
10 May 1991
TL;DR: In this paper, image frames are first arranged in a hierarchy of decimation levels, and a first error signal is generated by comparing corresponding levels of decimated background data with current image data.
Abstract: To improve reproduction of images transmitted over a narrow-band channel (20), image frames are first arranged in a hierarchy of decimation levels. A first error signal is generated by comparing corresponding levels of decimated background data with current image data, and second error data is generated by comparing corresponding levels of frame-predicted warped data also with the current image data. These two error signals are then compared to determine which data more closely represents the current image data. In another embodiment, motion compensation is used.

83 citations


Journal ArticleDOI
TL;DR: In this paper, the authors show that pre-processing and proper cloud-screening of CZCS data are necessary for accurate satellite-derived pigment concentrations, especially in the coastal margins, where pigment content is high and image distortion associated with electronic overshoot.
Abstract: Clouds are removed from Coastal Zone Color Scanner (CZCS) data using channel 5. Instrumentation problems require pre-processing of channel 5 before an intelligent cloud-screening algorithm can be used. For example, at intervals of about 16 lines, the sensor records anomalously low radiances. Moreover, the calibration equation yields negative radiances when the sensor records zero counts, and pixels corrupted by electronic overshoot must also be excluded. The remaining pixels may then be used in conjunction with the procedure of Simpson and Humphrey to determine the CZCS cloud mask. These results plus in situ observations of phytoplankton pigment concentration show that pre-processing and proper cloud-screening of CZCS data are necessary for accurate satellite-derived pigment concentrations. This is especially true in the coastal margins, where pigment content is high and image distortion associated with electronic overshoot is also present. The pre-processing algorithm is critical to obtaining accurate global estimates of pigment from spacecraft data.

31 citations


Journal ArticleDOI
TL;DR: A diode-laser driven all-optical iterative processor has been constructed and tested and results are presented showing operation equivalent to a single channel of the cellular logic image processor architecture.
Abstract: A diode-laser driven all-optical iterative processor has been constructed and tested. Results are presented showing operation equivalent to a single channel of the cellular logic image processor architecture. Functional features of the circuit include optically programmable logic, thresholding, and data synchronization. Essential elements such as cascadability, logic-level restoration, and data feedback have been demonstrated with the optical processor controlled by a conventional electronic computer. Serial processing algorithms for word recognition, comparison, full addition, and subtraction have been implemented. Comments on the reliability of operation and future plans for expansion are made.

29 citations


Patent
27 Sep 1991
TL;DR: Light assembly for providing a focused image of varying color hue and saturation intensity is described in this article, where a point light source, a filter set in which the filters are complementary colors, and a light mixing channel to pass additively mixed light rays to an objective lens system which produces the focused image.
Abstract: Light assembly for providing a focused image of varying color hue and saturation intensity which includes means for providing a point light source, a filter set in which the filters are complementary colors, and a light mixing channel to pass additively mixed light rays to an objective lens system which produces the focused image.

28 citations


Proceedings ArticleDOI
14 Apr 1991
TL;DR: A computational image analysis model that resembles the functioning of the brain and consists of three stages: multiple-channel representation, neural network classification and spatial context correction is introduced.
Abstract: A computational image analysis model that resembles the functioning of the brain is introduced. The multiple-channel neural network model consists of three stages: multiple-channel representation, neural network classification and spatial context correction. The model is implemented and applied to the problem of texture analysis. Gabor filters are involved to represent the textural patterns. Low misclassification rates are obtained. Composite textural images are also applied to the system and accurately segmented images are obtained. The usefulness of the model is demonstrated. >

14 citations


Journal ArticleDOI
TL;DR: Results on synthetic and real channel currents suggest that this algorithm will substantially increase the productivity of many laboratories involved in ionic-channel research.
Abstract: An automatic channel detection algorithm is proposed. This algorithm is based on sequential minimization of an index which is usually used in cluster analysis. The algorithm consists of two stages, namely segmentation and classification. In the first stage, the signal samples are segmented based on the assumption that the samples in each segment should be sequentially connected. In the second stage, the resultant segments are classified with no regard to their connectivities. The algorithm is computationally fast and globally optimum. The criterion function used in this algorithm is the ratio of the within-class variation over the between-class variation. An information-theoretic criterion that can be used mainly as a stopping rule in the segmentation stage is also proposed. Results on synthetic and real channel currents suggest that this algorithm will substantially increase the productivity of many laboratories involved in ionic-channel research. >

13 citations


Patent
Kiminori Ishizuka1
10 May 1991
TL;DR: In this article, a simple and compact configuration of a graphic recording method for multi-channel measurement data is presented. But the method is not suitable for the handling of complex data, as it requires quick and minute changes without causing a trouble in accurate reading of the recorded data.
Abstract: A graphic recording method and a graphic recording apparatus capable of dealing with the multi-channel measurement data involving quick and minute changes, without causing a trouble in accurate reading of the recorded data, in a simple and compact configuration. In the apparatus, the multi-channel measurement data are recorded by plotting a monochromatic continuous line for each channel of the multi-channel measurement data on a recording paper; and a channel discrimination mark having a distinctive color is plotted, with respect to each monochromatic continuous line, at a regular interval.

10 citations


Journal ArticleDOI
TL;DR: Dannemiller's (1989) computational approach to color constancy is discussed and an alternative type of descriptor is available that is not used to recover reflectance spectra that has the advantage of allowing an interpretation that is preferable from a human perceptual point of view.
Abstract: Dannemiller's (1989) computational approach to color constancy is discussed in relation to human color constancy. A reflectance channel that requires a priori information is shown to be less plausible for the human visual system than Dannemiller argued. The resemblance of Dannemiller's hypothetical visual system to the human visual system is misleading because it implies that surface reflectance is the illuminant-invariant object color descriptor that the human visual system uses to achieve color constancy. However, an alternative type of descriptor is available that is not used to recover reflectance spectra. It has the advantage of allowing an interpretation that is preferable from a human perceptual point of view.

7 citations


Journal ArticleDOI
15 Sep 1991
TL;DR: A systolic array which performs pyramidal algorithms is presented, which is tow-dimensional with one processor per image pixel; the number of steps in its execution is independent of the size of the image.
Abstract: Pyramidal algorithms manipulate hierarchical representations of data and are used in many image processing applications, for example, in image segmentation and border extraction. We present a systolic array which performs pyramidal algorithms. The array is tow-dimensional with one processor per image pixel; the number of steps in its execution is independent of the size of the image. The derivation of the array is governed by a mechanical method whose input is a Pascal-like program. After a number of manual transformations that prepare the program for the method, correct and optimal parallelism is infused mechanically. A processor layout is selected, and the channel connections follow immediately.

5 citations


Patent
19 Feb 1991
TL;DR: In this article, a plug-to-plug compatible pixel decoder palette is provided which is responsive to a predetermined sequence of commands on an I/O data channel to switch the mode of operation of the pixel coder palette.
Abstract: In a pixel display system, a plug-to-plug compatible pixel decoder palette is provided which is responsive to a predetermined sequence of commands on an I/O data channel to switch the mode of operation of the pixel decoder palette. The pixel coder palette comprises a random access memory used as a look-up table to store colors to be displayed and the I/O channel is used to store new colors in or read colors out from the random access memory. The different modes of operation of the pixel decoder palette involve operating on intensity values represented by 6-bit bytes and 8-bit bytes and involve continuous edge graphics wherein pixels bridging boundaries between objects are displayed as mixes of the colors on each side of the boundary.

4 citations


Journal ArticleDOI
TL;DR: A single-channel alternative detection system for magnetic resonance imaging and spectroscopy experiments is presented and it is possible to use the Hartley instead of the Fourier transform.
Abstract: A single-channel alternative detection system for magnetic resonance imaging and spectroscopy experiments is presented. After the phase error identification, which is realized through a simple method, one can correct the reconstructed image and discriminate between positive and negative frequencies without any loss of the S/N ratio. Since there is only one channel, that is a real signal, it is possible to use the Hartley instead of the Fourier transform. The former is faster and requires less storage memory. >

Dissertation
01 Jul 1991
TL;DR: Good segmentation results are obtained, with more than 92% of the pixel population of each of the test images (derived from Brodatzs texture album) being correctly classified by all the three approaches.
Abstract: This study is dedicated to the problem of segmenting monochrome images into distinct homogeneous regions by texture properties. The principle of the approaches to texture segmentation adopted in this thesis is mapping a textured image into a grey level image so that conventional segmentation techniques by intensity can be applied. Three novel approaches to texture segmentation have been developed in this thesis. They are called the Local Feature Statistics Approach (LFS), the Local Spectral Mapping Approach (LSM) and the Multichannel Spatial Filtering Approach (MSF). In the LFS approach, a multiresolution scheme for extracting texture features is introduced. This scheme produces features which can describe texture characteristics at different resolution levels. The gradient vector at each resolution level is used as the local texture feature. Based on the population statistics of gradient magnitude and direction in a local observation window, two novel texture measures, named as the Linear Gradient Magnitude Enhancement Measure (LGME) and the Linear Gradient Direction Enhancement Measure (LGDE), are developed to enhance different texture characteristics. In the LSM approach, the new scheme for the extraction of local texture features is based on performing transformations on the power spectra of local regions. The power spectrum of a local region is divided into a number of rings or wedges, and local spectral vectors are formed by summing the energy in these rings or wedges as vector elements. Two new texture measures, named as the Linear Radial Feature Enhancement Measure (LRFE) and the Linear Angular Feature Enhancement Measure (LAFE), are developed to highlight different texture characteristics. The MSF approach is based on the Multichannel Spatial Filtering Model (MSFM) for the human visual cortex. It is assumed in this approach that a texture can be characterised by its principal spatial frequency components, and that these components can be captured by a number of narrowband spatial filters. A new class of filters, called the Gaussian-Smoothed Fan (GSF) filters, is developed to perform channel filtering operations. The passband characteristic of these GSF filters is flatter than that of the Gabor filters, thus their bandwidths are inherently better defined. Computational algorithms based on these three new approaches are implemented and applied to a set of textured images. Good segmentation results are obtained, with more than 92% of the pixel population of each of the test images (derived from Brodatzs texture album) being correctly classified by all the three approaches. By comparison, the newly-developed GSF filters used in the MSF approach have an important advantage over the Gabor filters in that they can produce better defined boundaries between texture regions.

Proceedings ArticleDOI
Geert C. Damstra1, A. H. Eenink1
01 Apr 1991
TL;DR: A 16 channel 10 MHz image detection system is described that can be used for streak photography and is used for high current arc research but other applications ate possible.
Abstract: A 16 channel 10 MHz image detection system is described that can be used for streak photography. By use of 16 multiplexers (lOx) a frame mode with 10x16 pixels is possible at 1 million frames per second during 1.6 msec. The light from the image plane is collected by 160 high fibres. The reconstruction of the image is made on a specially designed LED monitor or on a standard computer. Data transfer is made by parallel-series-interface with two light fibres. The system is used for high current arc research but other applications ate possible.

Patent
24 Apr 1991
TL;DR: In this paper, a double-channel optical interface device is used for endoscope image displays, which belongs to the field of medical instruments and has the advantages of small size, light weight, complete functions and convenient operation.
Abstract: The utility model relates to a double-channel optical interface device used for endoscope image displays, which belongs to the field of medical instruments. Optical images output by various medical speculums and medical eyepieces can be imaged on the target side of a microminiatureCCD color camera through the optical interface device, and then, the images can be transmitted to a color image recording and displaying system through a video cable. Meanwhile, the endoscope images can be directly observed through the optical interface device. The utility model has the advantages of small size, light weight, complete functions and convenient operation, which can be matched with various medical endoscopes with wide application on clinical diagnoses and treatments and medical teaching as well as scientific research in various hospitals.

Proceedings ArticleDOI
22 May 1991
TL;DR: A 2/3 inch interline CCD image sensor for NTSC system with 250000 pixels has been developed that adopts buried channel CCD and vertical overflow drain structure for high charge transfer efficiency/low noise and good antiblooming/smear reduction capability respectively.
Abstract: A 2/3 inch interline CCD image sensor for NTSC system with 250000 pixels has been developed. This device adopts buried channel CCD and vertical overflow drain structure for high charge transfer efficiency/low noise and good antiblooming/smear reduction capability respectively. It was fabricated by a double-p-well double-poly double-metal technology, and 1.5 mu m design rule process. Gettering was also applied for dark current reduction. On chip color filter, Y/Cy/G complementary color, checkerboard pattern, was developed for color image sensing. >


Patent
29 May 1991
TL;DR: In this paper, the authors proposed a method to relieve an operator of his work load and carry out an accurate potting, not by permitting him to macroscopically watch the potting channel of a resin and teach it to an XYZ driving gear, but by teaching the Potting channel calculated on the basis of an image sensed by means of an overhead image sensing camera.
Abstract: PURPOSE: To relieve an operator of his work load and carry out an accurate potting, not by permitting him to macroscopically watch the potting channel of a resin and teach it to an XYZ driving gear but by teaching the potting channel calculated on the basis of an image sensed by means of an overhead image sensing camera. CONSTITUTION: In a potting apparatus 15, a syringe 6 and an image sensing camera 16 are interlocked one another. While the image from the image sensing camera 16 is macroscopically watched on a monitor display 18, the image sensing camera 16 is moved along the potting channel, then the working momentum of an XYZ driving gear 7 required to move the syringe 6 along the potting channel is calculated on the basis of the potting channel imaged by the image sensing camera 16 and the XYZ driving gear is operated according to the so obtained working momentum. Accordingly, the potting channel calculated with a vertical image sensed by the image sensing camera is taught to relieve an operator of his work load and further to carry out an accurate potting. COPYRIGHT: (C)1992,JPO&Japio

Proceedings ArticleDOI
01 Mar 1991
TL;DR: In this paper, an integrated image segmentation method using edge and needle map is presented, which compensates the deficiencies of using either edge-based approach or region-based method.
Abstract: This paper presents an integrated image segmentation method using edge and needle map which compensates deficiencies of using either edge-based approach or region-based approach. Segmentation of an image is the first and most difficult step toward symbolic transformation of a raw image, which is essential in image understanding. In industrial applications, the task is further complicated by the ubiquitous presence of specularity in most industrial parts. Three images taken from three different illumination directions were used to separate specular and Lambertian components in the images. Needle map is generated from Lambertian component images using photometric stereo technique. In one channel, edges are extracted and linked from the averaged Lambertian images providing one source of segmentation. The other channel, Gaussian curvature and mean curvature values are estimated at each pixel from least square local surface fit of needle map. Labeled surface type image is then generated using the signs of Gaussian and mean curvatures, where one of ten surface types is assigned to each pixel. Connected regions of identical surface type pixels provide the first level grouping, a rough initial segmentation. Edge information and initial segmentation of surface type are fed to an integration module which interprets the edges and regions in a consistent way. During interpretation regions are merged or split, edges are discarded or generated depending upon global surface fit error and consistency with neighboring regions. The output of integrated segmentation is an explicit description of surface type and contours of each region which facilitates recognition, localization and attitude determination of objects in the image.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

01 Jan 1991
TL;DR: Compared to ordinary VQ, two-channel conjugate VQ requires less computational complexcity and less storage (memory) and is more robust against channel errors and is combined with a conventional image coding technique.
Abstract: Two-channel conjugate VQ (TCCVQ) has been recently proposed for speech coding. Compared to ordinary VQ, two-channel conjugate VQ requires less computational complexcity and less storage (memory) and is more robust against channel errors. This technique is now extended to image coding. The emphasis in this paper is on the usefulness of the TCCVQ when it is applied to image coding or is combined with a conventional image coding technique. Initial investigation confirms these advantages of two-channel conjugate VQ. For a noise-free channel the performances of both techniques are similar. However, when channel noise is injected, for the same bit rate, images reconstructed based on two-channel conjugate VQ are subjectively more pleasing (have less visible distortion) than those based on ordinary VQ. Both VQ techniques are also applied to a well-known separating mean VQ and are tested for robustness against channel errors. Computer simulations demonstrate the success of the two-channel conjugate VQ technique for image data compression at various bit rates.

Patent
11 Oct 1991
TL;DR: In this paper, the color picture scanner of high resolution for all three colors by using the reading system of the high-resolution for only a monochromatic one channel portion in addition to the color input system of low resolution is generated.
Abstract: PURPOSE:To realize the color picture scanner of high resolution for all three colors by using the reading system of the high resolution for only a monochromatic one channel portion in addition to the color input system of low resolution. CONSTITUTION:Only a standard color picture is read by a high resolution, and the other two colors are read from the output of the separation system of the low resolution, and the picture signal of the high resolution for all three colors is generated. An original picture 1 is three-color-separtion-scanned first by the resolution coarser than a prescribed picture element in order to calculate a parameter, and it becomes the coarse pictures 2, 3, 4 of R, G, B respectively. Next, the approximate solutions of the parameter [r0, r1] of red and the parameter [b0, b1] of blue are derived for every block from the coarse pictures 2, 3, 4 of R, G, B. Next, the signal of the high resolution for all three colors is obtained by using the parameters and the standard color picture signal of the high resolution.

01 Jan 1991
TL;DR: This paper explains the technological and perceptual problems associated with the use of color computer display systems, and then offers a solution for the effective use ofcolor regardless of the viewer's ability to perceive color.
Abstract: The advancement of microcomputer technology has reached the point where color monitors and color computer software are fast becoming the norm in our information society. Color is another channel for communication, and can be used for enhancement of both aesthetic characteristics and productivity. The advantage to the use of color for communication is that there is an increased capacity to convey information in the message. The disadvantage is that the information contained in the color channel may not be perceived by approximately eight percent of the population who have impaired color vision. Misperceiving color information may result in not seeing such important messages as heading: on a spreadsheet or the distinct colored sections in a pie chart. This paper explains the technological and perceptual problems associated with the use of color computer display systems, and then offers a solution for the effective use of color regardless of the viewer's ability to perceive color. (14 references) (Author/DB) *********************************************************************** Reproductions supplied by EDRS are the best that can be made from the original document. ******************************************************************* 4 U.S. DEPARTMENT OF EDUCATION Office of Educational Research and Improvement EDUCATIONAL RESOURCES INFORMATION CENTER (ERIC) CI This document has been reproduced as received from the person or organization originating it )4 Minor changes have been made to improve reproduction quality Points of view or opinions stated in this docu merit do not necessarily represent official OERI posmon or polily Computers and Color Perception 1 Using Color as Information in Computer Displays: Problems with Perception and Communication

Patent
25 Dec 1991
TL;DR: In this paper, an image obtained through an objective lens l is separated into three R, G and B colors by a prism and respective images are formed on three CCD image sensors 3 to 5.
Abstract: PURPOSE:To improve vertical resolution without reducing the whole sensitivity by setting up the accumulation time of B channel having less signal quantity to the longest value and setting up that of G channel exerting large influence upon the resolution to a short value. CONSTITUTION:An image obtained through an objective lens l is separated into three R, G and B colors by a prism and respective images are formed on three CCD image sensors 3 to 5. Output signals from the sensors 3 to 5 are synthesized by a signal processing circuit 6 to obtain a color image signal. In the sensors 3 to 5, one of signal charge accumulation time values of picture elements corresponding to odd lines and picture elements corresponding to even lines is set up to the longest time t1, the other is set up to time t2 shorter than the time t1 and respective time values t1, t2, are inverted in each field. The accumulation time t2 of the CCD image sensor in the G channel is set up to the shortest value, the accumulation time t2 of the R channel CCD image sensor is set up to a slightly shorter value and the accumulation time t2 of the B channel CCD image sensor is set up to the maximum value equal to the time t1.

Proceedings ArticleDOI
01 Jun 1991
TL;DR: In this paper, a two-channel structure was proposed for the enhancement of low-contrast details of dental X-ray images using a two channel structure, which first decomposes an input image in the frequency domain into two parts by filtering and then these parts are enhanced separately using a transform magnitude modifier.
Abstract: In this paper, we develop a new algorithm for the enhancement of low-contrast details of dental X-ray images using a two channel structure. The algorithm first decomposes an input image in the frequency domain into two parts by filtering: one containing the low frequency components and the other containing the high frequency components. Then these parts are enhanced separately using a transform magnitude modifier. Finally a contrast enhanced image is formed by combining these two processed parts. The performance of the proposed algorithm is illustrated through enhancement of dental X-ray images. The algorithm can be easily implemented on a personal computer.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Patent
01 Aug 1991
TL;DR: In this article, the authors propose to allow a large number of images to be observed by varying the display speed of the image having information quantity exceeding the through-put of a communication line or channel, and that of an image not exceeding it in real time.
Abstract: PURPOSE:To allow a large number of images to be observed by varying the display speed of the image having information quantity exceeding the through- put a communication line or channel, and that of the image not exceeding it in real time. CONSTITUTION:The images 243, 244 of plural hierarchies from which the picture elements of an original image 22 are thinned are registered on an image data base 21 with the original image, and when the user of an image display terminal 1 requests the continuous display of the image at speed exceeding the throughput of the communication line or channel 3, an image data base center 2 transmits the image with the hierarchy of thinning rate corresponding to it continuously. When a request to vary the display speed is issued within a range of throughput, the original image is transmitted as it is, and the continuous display of the image is performed by taking a timing at a terminal side fitting in the request when transmission via the communication line is performed, and by taking the timing at a center side when it is performed via the channel. In such a way, it is possible to observe a large number of images in a short time, and to search a specific image out of a large number of images in a short time.

Patent
26 Dec 1991
TL;DR: In this paper, the hue of a video signal is always constant and optimum by providing a circuit deciding the hue in a video output and hue correction means changing a control signal in accordance with the input route of the video signal.
Abstract: PURPOSE:To demodulate a chrominance signal by means of a hue which is always constant and optimum by providing a circuit deciding the hue of a video output and hue correction means changing a control signal in accordance with the input route of a video signal CONSTITUTION:In the video signal, there is a case when the rotation angles of the phase of a burst signal differ by a transmission route is the receiver and the rotation angles of the hue differ by the channel of an RF signal In such a case, the rotation angle of the phase is previously measured and the size of the control signal equivalent to the rotation angle of the phase in the hue deciding circuit 65 is decided Then, the hue correction means 11, 12, 15 and 16 change the size of the control signal given to the hue deciding circuit 65 in accordance with the route of the video signal inputted to the receiver or the reception channel by a previously decided quantity Thus, the hue in the video output can always be made constant irrespective of an input source