Blackspot Or Shading Correction (e.g., Corrects For Fixed Pattern Defects) Patents (Class 348/615)
  • Patent number: 7215383
    Abstract: A display device or a receiver device for use with coherent light. A controller applies phase shift values to a multi-region phase array at a frequency sufficiently higher than the flicker fusion rate of the human eye or other intended receiver in order to remove the perception of speckling artifacts which would otherwise appear due to the coherency of the light.
    Type: Grant
    Filed: January 29, 2004
    Date of Patent: May 8, 2007
    Assignee: Intel Corporation
    Inventors: Eric C. Hannah, Michael O'Connor
  • Patent number: 7209180
    Abstract: A video output device adds a blank on both left and right sides or both upper and lower sides of an input video to produce a video having the same aspect ratio as that of the display screen of the display device, when an aspect ratio of the input video and an aspect ratio of a display device for displaying the video are different. At this time, the brightness of the blank to be added to the input video is adjusted in accordance with the brightness near the boundary between the input video and the blank to suppress a difference in brightness near the boundary.
    Type: Grant
    Filed: October 31, 2003
    Date of Patent: April 24, 2007
    Assignee: Funai Electric Co., Ltd.
    Inventors: Toshihiro Takagi, Tatsuo Miyagawa, Yasuhiro Inui
  • Patent number: 7202894
    Abstract: An image processing system and method compares each pixel of an image obtained from an image sensor array with at least eight surrounding pixels of the same color in the filter array. If the signal of a given pixel is larger than the respective signals of all eight surrounding pixels of the same color, then the value of that central pixel signal is substituted with the maximum signal value among the surrounding eight pixels of the same color. Similarly, if the signal of a given pixel is smaller than the respective signals of all eight surrounding pixels of the same color, then the value of that central pixel signal is substituted with the minimum signal value among the surrounding eight pixels of the same color.
    Type: Grant
    Filed: June 4, 2002
    Date of Patent: April 10, 2007
    Assignee: Micron Technology, Inc.
    Inventors: Michael Kaplinsky, Igor Subbotin
  • Patent number: 7184098
    Abstract: A system and method for reducing periodic intensity variation in a video image includes applying input signals representing video image data to multiple circuit components by sequentially shifting the input signals through the circuit components to produce output signals that match corresponding input signals. Matching the output signals to the input signals overcomes the effect of inherent differences in characteristics of analog circuit components. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or the meaning of the claims.
    Type: Grant
    Filed: February 19, 2004
    Date of Patent: February 27, 2007
    Assignee: Spatialight, Inc.
    Inventors: Charles D. Pencil, Michael S. Jin
  • Patent number: 7148933
    Abstract: A projector employing a linear array of light-emitting sources forms a super pixel in the form of a plurality of beams that are focused onto scanning optics that cause the beams to move across a viewing surface on a first axis for defining image lines along the first axis and on a second axis such that super pixel overwrites every addressable spot on the viewing surface thereby producing interleaved and staggered scan patterns that hide the effect of burned out, misdirected, or marginally operating light-emitting sources that would otherwise result in a degraded projected image. An alignment system that includes alignment electronics that is responsive to a charge-coupled device facilitate adjusting the scanning optics to allow precise alignment of individual ones of the light-emitting sources and to detect burnt out individual ones of the light-emitting sources.
    Type: Grant
    Filed: January 21, 2003
    Date of Patent: December 12, 2006
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventor: Winthrop D. Childers
  • Patent number: 7084911
    Abstract: The present invention provides a method and apparatus for calibrating a black level in an imager to reduce flicker noise. A first and a second range is set. The first range corresponds to a range that is larger than a noise level at a highest PGA gain. The second range corresponds to a range that is smaller than a level which reduces an ADC dynamic range too much due to a large black level. The ranges may be adjusted to changes in an imager in real time. When the black level is within the second range a determination is made as to whether the black level has been calibrated before. When it has, the DAC output is held constant. Otherwise the DAC code is adjusted such that the black level is moved toward the first range. A small step size is used in adjusting the DAC code in order to reduce flicker. Step sizes may be adjusted according to the black level in relation to the ranges. A small step size is used when the black level is within the second range.
    Type: Grant
    Filed: November 8, 2002
    Date of Patent: August 1, 2006
    Assignee: Eastman Kodak Company
    Inventors: Bumha Lee, Andrew Kenneth John McMahon
  • Patent number: 7075569
    Abstract: A digital camera which is an image processing apparatus is controlled so that a first image and a second image are acquired for the same subject in different timings. A plurality of correction tables for use in shading correction are prepared in advance in a shading ROM of the digital camera. When a first image and a second image are acquired, multiplication of one correction table is performed on both images by a shading correction circuit. As a result of this, a shading correction is effected on both images. The first image and the second image that have been subjected to the shading correction are taken into respective image memories, and after being subjected to a positioning process by a general controller, they are synthesized to generate a synthesized image.
    Type: Grant
    Filed: March 19, 2002
    Date of Patent: July 11, 2006
    Assignee: Minolta Co., Ltd.
    Inventor: Masahito Niikawa
  • Patent number: 6963373
    Abstract: An image processing apparatus which eliminates noise which occurs due to the influence of output from a parallel bus drive circuit added to an output final stage circuit of signal processor or the like. A delay circuit 110 which delays a video signal is inserted into a VTR signal processor such that a data transition point of particular bit in a bit array indicating horizontal-directional start and end positions of video signal data, added during a horizontal retrace period of a digital recording format video signal, does not overlap with a period for sampling a feedthrough period and a photoelectric conversion signal period in a correlated double sampling circuit.
    Type: Grant
    Filed: June 20, 2001
    Date of Patent: November 8, 2005
    Assignee: Canon Kabushiki Kaisha
    Inventor: Kazuhiro Imaizumi
  • Patent number: 6958785
    Abstract: The need is met according to the present invention by providing a method of correcting pixel by pixel variations in a display, the method including the steps of creating a defect map of pixel intensity offsets for the display; correcting an input signal according to the defect map; and displaying the corrected input signal on the display, wherein the offset defect map is created by modulating a pixel in the display at a predetermined rate at a predetermined intensity; sensing the display with a photosensor to generate a sensed signal; demodulating the signal with a synchronous demodulator at the predetermined rate to produce a demodulated signal representing a sensed intensity; and employing the sensed intensity and the predetermined intensity to generate a correction offset.
    Type: Grant
    Filed: October 22, 2001
    Date of Patent: October 25, 2005
    Assignee: Eastman Kodak Company
    Inventors: William A. Orfitelli, William R. Markis
  • Patent number: 6859493
    Abstract: The system and method of the present invention provides an innovative technique and efficient hardware structure for recovering lost or damaged (lost/damaged) compression constants in the encoded domain. In one embodiment, a lost/damaged compression constant is recovered by estimating a compression constant of the block using encoded data of at least one neighboring block of data and other recoverable compression constants of the block.
    Type: Grant
    Filed: June 29, 1999
    Date of Patent: February 22, 2005
    Assignees: Sony Corporation, Sony Electronics Inc.
    Inventors: Tetsujiro Kondo, James J. Carrig, Yasuhiro Fujimori, Sugata Ghosal
  • Patent number: 6768518
    Abstract: A wavelet domain filtering technique is disclosed that removes or at least minimizes checkerboard-like noise artifacts that result from capturing a composite NTSC video signal. A Haar basis filter bank is used to obtain a two-level wavelet decomposition. Low-pass filtering is performed on the high-high (HH) and the high-low (HL) bands of the wavelet decomposition since the checkerboard-like noise artifact is primarily visible on the vertical and the diagonal edges of the captured composite NTSC video frame.
    Type: Grant
    Filed: December 16, 1998
    Date of Patent: July 27, 2004
    Assignee: Xerox Corporation
    Inventor: Gozde Bozdagi
  • Publication number: 20040125886
    Abstract: The present invention relates to a system and method for improving the waveform at a receiver. More specifically, the present invention relates to a system adapted to modify at least one signal in anticipation of channel attenuation and delay. The present invention comprises a memory adapted to store at least one coefficient that is pre-determined based on at least one expected degradation characteristic of a channel; and a pre-emphasizer communicating with at least the memory and the channel, and adapted to modify the at least one signal using the at least one coefficient prior to transmission of the at least one signal over the channel, compensating for the at least one expected degradation characteristic.
    Type: Application
    Filed: December 11, 2002
    Publication date: July 1, 2004
    Inventor: Richard S. Berard
  • Patent number: 6741666
    Abstract: A method and a device by which original digital signals are analysis-filtered, where the original digital signals include original samples representing physical quantities, and where the original samples are transformed by successive calculation steps into high and low frequency output samples. Any sample calculated at a given step is calculated by a predetermined function of the original samples and/or previously calculated samples, where the samples are ordered by increasing rank. The signal is processed by successive input blocks of samples, where the calculations made on an input block under consideration take into account only the original or calculated samples belonging to the input block under consideration, and where the input block under consideration and the following input block overlap over a predetermined number of original samples. Output blocks are formed, where each output block corresponds respectively to an input block.
    Type: Grant
    Filed: January 11, 2000
    Date of Patent: May 25, 2004
    Assignee: Canon Kabushiki Kaisha
    Inventors: FĂ©lix Henry, Bertrand Berthelot, Eric Majani
  • Patent number: 6737625
    Abstract: A sensor includes an array of photodetectors each generating an output signal of pixel data indicative of incident light intensity. This pixel data is read out from the array one line at a time and stored in a line buffer. A bad pixel processor includes a first buffer that stores pixel data obtained from the line buffer for a certain pixel in a currently read out line and pixel signal light data for pixels adjacent to the certain pixel.
    Type: Grant
    Filed: June 28, 2001
    Date of Patent: May 18, 2004
    Assignee: Agilent Technologies, Inc.
    Inventors: Izhak Baharav, Ramakrishna Kakarala, Xuemei Zhang, Dietrich Werner Vook
  • Patent number: 6650372
    Abstract: A method and apparatus for providing a flicker filter for an interlaced video display. Content is analyzed to determine what type of filter or filter characteristics selected from a plurality of available filters or filter characteristics can provide the better display of the content. Based on this analysis, the filter characteristics are selected and used for flicker filtering the content for display.
    Type: Grant
    Filed: January 22, 2001
    Date of Patent: November 18, 2003
    Assignees: Sony Corporation, Sony Electronics, Inc.
    Inventor: Rolf Toft
  • Publication number: 20030086020
    Abstract: In order to reduce the total capacity of a ROM used for adjustment of the black level and the white level of a digitized luminance signal for a television receiver, for example, a comparator compares the input luminance signal with a predetermined threshold value, a NOT gate inverts the input luminance signal, a first switching unit selects the input luminance signal or the output of the NOT gate, a ROM outputs an adjustment characteristic signal responsive to the output of the first switching unit, a multiplier multiplies the output of the ROM by a weighting signal and outputs the result of the multiplication as an adjustment value, a subtractor subtracts the adjustment value from the input luminance signal, an adder adds the adjustment value to the input luminance signal, and a second switching unit selects the output of the subtractor or the output of the adder.
    Type: Application
    Filed: March 26, 2002
    Publication date: May 8, 2003
    Inventors: Toshihiro Gai, Yoshiaki Okuno, Jun Someya, Masaki Yamakawa
  • Patent number: 6559895
    Abstract: Fixed pattern noise of an analog memory is reduced. Transfer paths of an address selection signal (SL) between an address generation unit (10) and respective storage elements (21) for storing an analog signal are constructed to have a substantially uniform electric characteristic in driving the storage elements (21) by the address selection signal (SL) to such an extent that the output signal of the analog memory is free from fixed pattern noise. A buffer unit (50) for temporarily storing and outputting the address selection signal is provided between the address generation unit (10) and the respective storage elements (21), and the buffer unit (50) is constructed to have an output characteristic substantially uniform between the storage elements (21). Also, lines between the buffer unit (50) and the storage elements (21) are constructed to have substantially the same electric characteristic.
    Type: Grant
    Filed: March 10, 2000
    Date of Patent: May 6, 2003
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Shiro Dosho, Naoshi Yanagisawa, Masayuki Ozasa, Hidehiko Kurimoto, Tatsuo Okamoto
  • Patent number: 6535617
    Abstract: A method of removing fixed pattern noise derives an estimate of fixed pattern noise from a composite media signal and uses the estimate to evaluate and remove fixed pattern noise from selected frames. The technique is particularly suited for removing fixed pattern noise in images due to image capture processes, but applies to other media signals as well. In watermarking applications, the method can be used to improve detection and recovery of a watermark. Also, it may be used to remove components of a watermark or a watermark from a cover signal that contains two or more different watermarks.
    Type: Grant
    Filed: April 19, 2000
    Date of Patent: March 18, 2003
    Assignee: Digimarc Corporation
    Inventors: Brett T. Hannigan, Brett A. Bradley, Geoffrey B. Rhoads
  • Patent number: 6493039
    Abstract: A method and system for reducing white noise in images. The method does not require knowledge of the image blur or noise statistics, and can remove noise without causing excessive image blur. The image is separated into frequency bands which are then thresholded to remove small image changes, i.e. noise, while maintaining larger changes which are signals. The thresholded components are then recombined to produce an output image with reduced white noise.
    Type: Grant
    Filed: January 19, 1999
    Date of Patent: December 10, 2002
    Assignee: Xerox Corporation
    Inventor: Steven J. Harrington
  • Patent number: 6490008
    Abstract: A method of removing a noise artifact from a video frame captured from a composite NTSC video signal is disclosed. The captured video frame is stored in a first buffer and includes a first plurality of pixels forming a first interlaced video field and a second plurality of pixels forming a second interlaced video field. For each interlaced field, a first pixel element is accessed from the first buffer, it is then determined whether the first pixel element is associated with an artifact in the video frame based on values of a first number of pixel elements including a value of the first pixel element. An adjusted value of the first pixel element is calculated based on values of a second plurality of pixel elements including the value of the first pixel element when the first pixel element is associated with an artifact in the video frame.
    Type: Grant
    Filed: August 13, 1999
    Date of Patent: December 3, 2002
    Assignee: Xerox Corporation
    Inventor: Steven J. Harrington
  • Patent number: 6466273
    Abstract: An analog FIFO memory device allowing for the suppression of the adverse effects produced by fixed pattern noise, generated inside an analog FIFO memory, on signal components. First and second analog multipliers are respectively provided on the input and output sides of the analog FIFO memory. In synchronism with the inputs/outputs of signals to/from the analog FIFO memory, a non-inverting operation and an inverting operation are alternately and repeatedly performed on the input signals and the output signals. Then, although the signal input/output characteristics of the analog FIFO memory are not changed, the fixed pattern noise generated inside the analog FIFO memory is modulated by the second analog multiplier. As a result, the spectrum of the fixed pattern noise, which originally has a lower frequency, is shifted to have a higher frequency.
    Type: Grant
    Filed: May 13, 1998
    Date of Patent: October 15, 2002
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Shiro Dosho, Naoshi Yanagisawa
  • Publication number: 20020135701
    Abstract: A method and apparatus for providing a flicker filter for an interlaced video display. Content is analyzed to determine what type of filter or filter characteristics selected from a plurality of available filters or filter characteristics can provide the better display of the content. Based on this analysis, the filter characteristics are selected and used for flicker filtering the content for display.
    Type: Application
    Filed: January 22, 2001
    Publication date: September 26, 2002
    Inventor: Rolf Toft
  • Patent number: 6456337
    Abstract: In a moving image correcting circuit for a display unit wherein a motion vector detecting portion detects inter-frame motion vectors and a moving image correcting position corrects the display positions of subfields for pixels in blocks, based on the detection values, the picture quality is protected from being degraded by preventing the output of an erroneous motion vector due to noise in, or fluctuation of, the input image signal or else preventing the erroneous motion vector, even if output from the motion vector detecting portion, from entering the moving image correcting portion.
    Type: Grant
    Filed: August 27, 1999
    Date of Patent: September 24, 2002
    Assignee: Fujitsu General Limited
    Inventors: Masayuki Kobayashi, Masamichi Nakajima, Hayato Denda
  • Publication number: 20020130974
    Abstract: When power is turned on, dummy output information stored in a non-volatile memory is issued to the digital signal processing circuit. In a dummy data processing block, and in a line memory holding data in the horizontal direction, dummy data inputted from outside is inserted into a one-line video data processed at an input signal processing block, based on the dummy output information. In this way, the video data is revised into data that is appropriate for each display, based on the dummy output information. Then the one-line video data including the dummy data is inputted into the output signal processing block, and is latched by the output signal processing block, and outputted to each of the data drivers as a data driver output signal, at the same time.
    Type: Application
    Filed: March 14, 2002
    Publication date: September 19, 2002
    Applicant: NEC CORPORATION
    Inventors: Toru Kimura, Goro Ueda
  • Patent number: 6441867
    Abstract: A method for extending bit-depth of display systems. The method includes the steps of measuring the static display noise of a display device, using the display noise to create pseudo-random noise and subtracting the pseudorandom noise from a contone image. After the noise-compensated image data is quantized and displayed, the noise in the display device will substantially convert the noise-compensated image data back to contone image data with few or no contouring artifacts. Other embodiments include using the inherent noise of the human visual system instead of the static display noise, or both. Specific adjustments can be made to the noise of the human visual system for color displays.
    Type: Grant
    Filed: October 22, 1999
    Date of Patent: August 27, 2002
    Assignee: Sharp Laboratories of America, Incorporated
    Inventor: Scott Daly
  • Publication number: 20020057373
    Abstract: Briefly, in accordance with one embodiment of the invention, a method of reducing flicker in a video image sequence includes the following. Successive video images are temporally filtered. The filter length is adjusted so as to reduce the amount of filtering across temporal discontinuities in the video image sequence.
    Type: Application
    Filed: December 26, 2001
    Publication date: May 16, 2002
    Inventor: Thomas P. O'Rourke
  • Publication number: 20020051090
    Abstract: An average luminance calculation section 7 calculating an average luminance of video data to output an average luminance level, latches 8 to 10 delaying said average luminance levels by one-frame portion respectively to output them, a LUT 2 outputting a pre-set maximum correction factor e when the video data is input, correction factor calculation sections 3 to 6, adders 11 and 12, and a multiplier 12 are provided, each of the correction factor calculation sections compares the corresponding average luminance level out of the average luminance levels, which were output, with a plurality of correction thresholds respectively to carry out weighting of the maximum correction factor e responding to the comparison result and to output it as each correction factor, and simultaneously the adders 11 and 11, and the multiplier 12 correct the luminance level of the video data based on the average value of these correction factors.
    Type: Application
    Filed: October 30, 2001
    Publication date: May 2, 2002
    Applicant: NEC CORPORATION
    Inventor: Seiki Onagawa
  • Patent number: 6363118
    Abstract: The system and method of the present invention provides an innovative technique and efficient hardware structure for recovering lost or damaged (lost/damaged) compression constants in the encoded domain. In one embodiment, a lost/damaged compression constant is recovered by estimating a compression constant of the block using encoded data of at least one neighboring block of data and other recoverable compression constants of the block.
    Type: Grant
    Filed: February 12, 1999
    Date of Patent: March 26, 2002
    Assignees: Sony Corporation, Sony Electronics, Inc.
    Inventors: Tetsujiro Kondo, James J. Carrig, Yasuhiro Fujimori, Sugata Ghosal
  • Patent number: 6359662
    Abstract: A method and system for compensating for defects in a multi-light valve display allows for the compensation of defective pixels in a display. By sequentially illuminating all light valves in a multi-light valve system with all colors, or wavelengths, available in the display, each light valve modulates the full gamut of colors available in the system. In this manner, the remaining light valves can compensate for a defective pixel in one of the light valves. The invention also includes an active compensation feature, whereby defective pixels in the display are identified and are compensated for by an associated display driver.
    Type: Grant
    Filed: November 5, 1999
    Date of Patent: March 19, 2002
    Assignee: Agilent Technologies, Inc.
    Inventor: Richard C. Walker
  • Patent number: 6310660
    Abstract: A method and apparatus for detecting video signal dropout. The method includes the step of generating a video signal, and then electronically isolating at least one component of the video signal. The at least one component is representative of the absence of the video signal itself. Next, the absence of the at least one component is electronically sensed. The step of electronically isolating can include the step of passing the video signal through a comb filter, and in particular isolating a luminescence signal from the video signal. The step of electronically isolating can also include passing the video signal through a sync separator. The step of electronically sensing can include passing the at least one component through a comparator. The method can also include the step of generating the video signal for a predetermined time duration, and simultaneously generating an audio signal to indicate the end of the predetermined time duration.
    Type: Grant
    Filed: March 18, 1998
    Date of Patent: October 30, 2001
    Assignees: Sony Corporation, Sony Electronics Inc.
    Inventors: Khaled Amin Abuali, Donato Yazurlo
  • Patent number: 6233019
    Abstract: The invention concerns a device and a method for converting a first image signal that is comprised of plural pixel data into a second image data that is comprised of plural pixel data. In particular, according to the image converter and the image converting method of the invention, even if the image quality of the inputted image data is poor, it is able to extract the optimal pixel data as the class tap or the predictive tap, and to perform the adequate prediction processing, since clipping of the class tap or the predictive tap is controlled in response to the feature quantity that represents the quantity of fuzz of the inputted image data.
    Type: Grant
    Filed: January 6, 1999
    Date of Patent: May 15, 2001
    Assignee: Sony Corporation
    Inventors: Tetsujiro Kondo, Yasushi Tatehira, Hideo Nakaya, Takaya Hoshino, Masaaki Hattori
  • Patent number: 6166782
    Abstract: A method and apparatus for reducing visibility of damping wire artifacts in aperture grill display tubes comprises a sensor device for locating the artifacts and responsively generating amplitude values, a processor for receiving the generated amplitude values and responsively calculating correction values, and a compensator device coupled to the processor for utilizing the correction values to correct said artifacts.
    Type: Grant
    Filed: January 29, 1997
    Date of Patent: December 26, 2000
    Assignee: Apple Computer, Inc.
    Inventor: Richard D. Cappels
  • Patent number: 6034724
    Abstract: A method and an apparatus are provided for eliminating a line-crawling phenomenon caused by nonuniformity in photosensitive characteristics of light-receiving pixels disposed in a color imaging device. A pixel signal (S) output from a color imaging device (2) is converted by a sample-and-hold circuit (4) and an A/D converter (6) into pixel data (P) so as to be stored in an image memory (8). An arithmetic unit (12) multiplies luminance data formed on the basis of each pixel data (P) by a line-crawling correction coefficient (LC) stored in a nonvolatile memory (10), for example, so as to form and output luminance data (V) which is substantially equivalent to that obtained when the light-receiving pixels have a uniform photosensitive characteristic. The line-crawling correction coefficient (LC) has been determined beforehand.
    Type: Grant
    Filed: February 3, 1997
    Date of Patent: March 7, 2000
    Assignee: Chinon Kabushiki Kaisha
    Inventor: Hideo Nakamura
  • Patent number: 5969709
    Abstract: A field emission display (FED) driver sequentially provided with an amplifier for amplifying an input video signal, a sample-and-hold circuit for sampling and holding the amplified video signal, a display having a plurality of pixels for displaying the signal sampled by the sample-and-hold circuit, and a biasing power source causing a field emission to the display, for generating an image, the FED driver includes a detector for detecting a current change of the respective pixels of the display, an analog-to-digital (A/D) converter connected to the output of the detector for converting the output signal of the detector into a digital signal, a memory device wherein the information which is a basis for the luminescence characteristics of the respective pixels is stored, a subtracter for receiving and differentiating the output signal of the A/D converter and the signal supplied from the memory device, a luminescence processor for obtaining the luminescence characteristics of the respective pixels supplied from
    Type: Grant
    Filed: January 9, 1998
    Date of Patent: October 19, 1999
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Jung-Woo Kim
  • Patent number: 5959680
    Abstract: A television system (TV) with an interlaced display screen for displaying network application data. Pixel data elements representing network application data display are received in a non-interlaced mode. The received data is filtered to reduce sharp transitions in the display. The filtered data is provided in an interlaced format (i.e., only alternate lines of a frame) for display on the television display screen. The interlaced image display is combined with the television signal display by selecting one of them on point by point basis. Flicker is reduced substantially in the final display of network application data due to the filtering.
    Type: Grant
    Filed: December 31, 1997
    Date of Patent: September 28, 1999
    Assignee: TeleCruz Technology, Inc.
    Inventor: Vlad Bril
  • Patent number: 5886750
    Abstract: In a television receiver, shading correction is carried out without deteriorating the S/N ratio. In a television receiver including a CRT, and a shading corrector for supplying an image signal to a cathode of the CRT (cathode-ray tube) and for correcting brightness inequalities of an image formed on a fluorescent screen by way of electron beams which are increased/decreased in response to a change in the potentials applied to a first grid of the CRT, the shading corrector supplies a shading correction signal to the first grid.
    Type: Grant
    Filed: May 22, 1996
    Date of Patent: March 23, 1999
    Assignee: Sony Corporation
    Inventors: Satoshi Osuga, Yoshihiro Inamoto, Hiroaki Kikuchi
  • Patent number: 5805216
    Abstract: A defective pixel correction circuit corrects a defective pixel in a solid imaging device such as a CCD exactly and sufficiently. A boundary detection circuit calculates magnitudes of boundaries from signals of eight peripheral pixels taken in a pixel taking-in circuit and a boundary ordering circuit compares the calculated magnitudes of the boundaries with one another to order the magnitudes of the boundaries. An interpolation circuit produces an interpolation signal in accordance with an interpolation method determined by an interpolation method determining circuit on the basis of the order of the ordered boundaries to correct the defective pixel.
    Type: Grant
    Filed: May 31, 1995
    Date of Patent: September 8, 1998
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Kenji Tabei, Masato Nishizawa
  • Patent number: 5751340
    Abstract: A method and apparatus for improving an image received from a endoscope having a flexible fiber optic bundle that produces an interstitial grid overlay due to the dead space between each fiber pixel. The interstitial grid pattern in the image, is substantially eliminated by processing the image through a linear digital filter to attenuate the first-order spatial frequency components that contribute most to the interstitial pattern. The filter employs relatively small convolution kernels that are optimized for specific fiber spacing. The image is then processed through the linear digital filter by convolving the respective pixels in the image by the derived coefficients. The image is improved and the grid pattern may also be reduced by a dilation process which involves processing the image through a dilation algorithm to "grow" the bright center of each fiber pixel in the image so that the effect of the grid pattern is reduced.
    Type: Grant
    Filed: August 21, 1996
    Date of Patent: May 12, 1998
    Assignee: Karl Storz GmbH & Co.
    Inventors: Karlheinz Strobl, Bryan D. Kennedy, David Chatenever, Klaus Irion
  • Patent number: 5748257
    Abstract: A picture information detecting apparatus includes a picture area signal output circuit to detect a picture area excluding black band portions from the input video signal to produce a picture area signal to designate the picture area from which picture information is detected. Also included is a picture information detecting circuit for detecting picture information from the input video signal in the designated area. A picture quality compensating circuit is also provided for compensating the video input signal using the detected picture information to produce the gradation compensated video signal. An EDTV 2 discriminating circuit may also be included to determine if the video input signal is an EDTV 2 signal.
    Type: Grant
    Filed: May 7, 1997
    Date of Patent: May 5, 1998
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Minoru Kawabata, Atsuhisa Kageyama
  • Patent number: 5583578
    Abstract: The gain of a variable gain amplifier for amplifying a video signal is changed in accordance with a brightness correction control signal that is output from a waveform ROM. The shape of the output signal of the waveform ROM is changed in accordance with a signal indicating the scanning position which signal is deformed in accordance with an external signal indicating a deviation of a hot spot.
    Type: Grant
    Filed: March 4, 1996
    Date of Patent: December 10, 1996
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Masaru Tateishi
  • Patent number: 5534945
    Abstract: In a system for the reproduction of natural images on a display or printer, unviewable negative brightness caused by noise or grain in individual shadow pixels, into adjacent pixels is diffused into adjacent pixels made excessively bright by the same noise or grain process. The visual effect of this diffusion produces truer, deeper blacks in shadow areas, enhances shadow contrast and detail, and reduces perceived noise in shadow areas.
    Type: Grant
    Filed: December 16, 1994
    Date of Patent: July 9, 1996
    Assignee: International Business Machines Corporation
    Inventor: Albert D. Edgar
  • Patent number: 5495298
    Abstract: An apparatus for concealing error data of pixel data in a digital image signal. The apparatus includes a deframing circuit for detecting errors every predetermined unit to generate a first error flag in high order bit planes including at least the most significant bit plane of bit planes of pixel data in a received digital image signal and for forming a second error flag representing the presence or absence of an error in each of the bits forming the pixel data every pixel data in the high order bit planes on the basis of the first error flag. The apparatus further includes an error correcting device for calculating a plurality of possible data values of the pixel data and for selecting one data value from among the plurality of possible data values, taking the correlation between the pixel data and surrounding pixel data into consideration, on the basis of the second error flag representing the presence or absence of an error in each of the bits forming the pixel data when the pixel data has an error.
    Type: Grant
    Filed: March 22, 1994
    Date of Patent: February 27, 1996
    Assignee: Sony Corporation
    Inventors: Masashi Uchida, Tetsujiro Kondo, Hideo Nakaya
  • Patent number: 5446501
    Abstract: According to a presently preferred embodiment of the invention, image enhancement apparatus for digital video images comprises a two-stage filter comprising a median filter and a recursive filter. The median filter operates in one, two, and three dimensions wherein the cluster of pixels framing the center pixel are ranked, and the median value of the pixel cluster is chosen as the correct pixel value. The pixel cluster configuration is selectable, as are the planes where the pixels are located. Multiple weights may be given to the appropriate median filter inputs. A motion detector is used to prevent replacement of each pixel by its pixel cluster median value when there is excessive motion. Finally an adjustable pixel-replacement threshold is defined. Each pixel must deviate from its median value before it is replaced by that value.
    Type: Grant
    Filed: October 22, 1992
    Date of Patent: August 29, 1995
    Assignee: Accom, Incorporated
    Inventors: Sohei Takemoto, Kenneth A. Woodhouse, Luigi C. Gallo, John D. Stern
  • Patent number: 5430502
    Abstract: In a vertical deflection circuit of a display monitor including a vertical deflection coil 41 and a sigmoid correction capacitor 42 connected to the vertical deflection coil 41, a series connection circuit consisting of a resistor 21 and a switch 22 connected in series with each other is connected in parallel with the sigmoid correction capacitor 42. By turning the switch 22 on and off in response to a control signal having a period twice as long as a period of the vertical synchronizing signal, a current flowing through the resistor 21 and the switch 22 is periodically added to a vertical deflection current, thereby causing shift of displaying points on a screen to make the moire phenomenon unnoticeable.
    Type: Grant
    Filed: February 24, 1993
    Date of Patent: July 4, 1995
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Masao Yamazaki, Tsutomu Kitamura
  • Patent number: 5416516
    Abstract: A solid-state image pickup apparatus for use as a video camera has a defect detecting mode and an operation mode. The solid-state image pickup apparatus includes a solid-state image sensor having pixels arranged in rows and columns for producing an output signal representing a detected image. The solid-state image sensor operates in a field reading mode for reading electric charges from the pixels in approximately one field period such that the electric charges of the pixels of two adjacent rows are summed before being outputted from the solid-state image sensor, the summed electric charges being different in even- and odd-numbered fields, and also operates in a frame reading mode for reading electric charges from the pixels in approximately one frame period such that the electric charges of the pixels of one of two vertically adjacent rows are read in even-numbered fields and the electric charges of the pixels of the other of two adjacent rows are read in odd-numbered fields.
    Type: Grant
    Filed: March 12, 1993
    Date of Patent: May 16, 1995
    Assignee: Sony Corporation
    Inventors: Takashi Kameyama, Yuuji Ohba
  • Patent number: 5412489
    Abstract: In an image reading apparatus, the standard data for the normalization of the image read data are obtained with use of a line memory of one line from the standard data of a plurality of lines. The white level data and the black level data are used for the normalization. The weight average of the input data of the standard data received successively one line by one converges gradually. The converged average is used for the correction of read data of an image, and the effect of image noises is reduced and the image read data is normalized at a high precision. In a continuous reading, only the white level may be updated for shortening the time for reading.
    Type: Grant
    Filed: June 26, 1992
    Date of Patent: May 2, 1995
    Assignee: Minolta Camera Kabushiki Kaisha
    Inventor: Yoshihiko Hirota
  • Patent number: 5410365
    Abstract: In an image pick up device, signal level of red, green and blue color signals is coarsely adjusted in a signal processing circuit, and then a black level of video signal is finely adjusted in a digital signal processing circuit, thereby being capable of easily adjusting the black level and improving the accuracy of black level adjustment.
    Type: Grant
    Filed: March 30, 1993
    Date of Patent: April 25, 1995
    Assignee: Sony Corporation
    Inventors: Koichi Nakamura, Takashi Asaida
  • Patent number: 5343302
    Abstract: A video camera includes a shading correction circuit in which a parabolic wave signal is generated and the level thereof is adjusted in accordance with zoom and iris settings of the camera's optical system. After adjustment, the parabolic wave signal is clipped in accordance with a reference level and the clipped parabolic wave signal is used for correcting the shading of the camera's image signal. The clipping of the parabolic correction signal allows for more accurate shading correction.
    Type: Grant
    Filed: November 9, 1992
    Date of Patent: August 30, 1994
    Assignee: Sony Corporation
    Inventor: Masahiro Yamashita
  • Patent number: 5337088
    Abstract: In signal processing method, bandwidth compression codes an image signal by blocks of plural proximal pixels, and outputs the decoded signal after decoding by the same block units. When a level difference occurs during decoding at the border between adjacent blocks, the level of the pixels near the block border is corrected so that the level difference is reduced before outputting the decoded signal. In addition, if the level difference between two pixels within the same block and at the border thereof is less than a predetermined level during decoding, and the difference between the level of two border pixels in adjacent blocks is greater than the level difference of the two pixels within the same block, the decoded signal is output after pixel level correction is applied near the block border to reduce the level difference of the two pixels in the adjacent blocks. Thus, the level difference between blocks is smoothed, and visual image deterioration resulting from block distortion can be greatly improved.
    Type: Grant
    Filed: September 7, 1993
    Date of Patent: August 9, 1994
    Assignee: Matsushita Electric Industrial Co. Ltd.
    Inventor: Masahiro Honjo
  • Patent number: RE38574
    Abstract: A method and apparatus for reducing visibility of damping wire artifacts in aperture grill display tubes comprises a sensor device for locating the artifacts and responsively generating amplitude values, a processor for receiving the generated amplitude values and responsively calculating correction values, and a compensator device coupled to the processor for utilizing the correction values to correct said artifacts.
    Type: Grant
    Filed: December 23, 2002
    Date of Patent: August 31, 2004
    Assignee: Apple Computer, Inc.
    Inventor: Richard D. Cappels