Responsive To Output Signal Patents (Class 348/228.1)
  • Patent number: 8243172
    Abstract: An SSG circuit section is composed of: a memory storing correction information for correcting a transmission characteristic of an image pickup signal in a transmission path; a readout circuit for reading out the correction information stored in the memory; and an SSG for generating a drive signal to be outputted from a driving circuit and a sampling pulse to be used in a CDS circuit, and for specifying an amplification factor of an amplifier circuit.
    Type: Grant
    Filed: April 21, 2009
    Date of Patent: August 14, 2012
    Assignee: Olympus Medical Systems Corp.
    Inventors: Hiroyuki Usami, Yutaka Fujisawa
  • Patent number: 8243165
    Abstract: A video camera includes an image sensor. The image sensor repeatedly outputs an object scene image produced on an imaging surface having a plurality of pixels lined up in a vertical direction. A driver repeatedly executes an exposing operation for exposing the imaging surface for each pixel lined up in a vertical direction. A CPU repeatedly detects a plurality of luminance values respectively corresponding to a plurality of flicker evaluation areas allocated to the imaging surface in a manner to be located at positions different from one another in a vertical direction, based on the object scene image outputted from the image sensor. Moreover, the CPU determines the presence or absence of a flicker based on the plurality of luminance values thus detected.
    Type: Grant
    Filed: November 4, 2009
    Date of Patent: August 14, 2012
    Assignee: SANYO Electric Co., Ltd.
    Inventors: Takeshi Fujiwara, Kazuhiro Tsujino, Kohei Fukugawa
  • Patent number: 8218029
    Abstract: Disclosed herein is an image taking apparatus including an image taking device, a gain adjustment circuit, and a correction circuit. The image taking device operates with timings based on a frame rate determined in advance and the total number of horizontal lines, has an electronic shutter allowing a shutter speed to be adjusted, receives light in a period equal to the shutter speed of the electronic shutter and carries out an opto-electrical conversion process on the light for every horizontal line in order to generate a predetermined signal. The gain adjustment circuit adjusts the gain of the electrical signal received from the image taking device. The correction circuit compares an image taking video signal with a reference video signal to compute a flicker component as a component oriented in the vertical direction of an image represented by the image taking video signal in a flicker correction process of eliminating flickers.
    Type: Grant
    Filed: August 25, 2009
    Date of Patent: July 10, 2012
    Assignee: Sony Corporation
    Inventor: Takahiro Nagai
  • Patent number: 8203624
    Abstract: An image-data processing apparatus includes an operation unit; a correcting unit multiplying image data generated by an image pickup device by a correction gain; a totalizing unit sequentially calculating a total pixel level for every frame from the image data; a history holding unit holding the total pixel levels of a certain number; an in-phase averaging unit detecting the total pixel levels in phase with a flicker phase corresponding to the image data that is being supplied to the correcting unit from the held total pixel levels to calculate a first average of the detected total pixel levels; an average calculating unit calculating a second average of the held total pixel levels; and a correction gain calculating unit calculating the correction gain by dividing the first average by the second average to set the correction gain in the correcting unit.
    Type: Grant
    Filed: April 8, 2010
    Date of Patent: June 19, 2012
    Assignee: Sony Corporation
    Inventor: Kazuhiro Sugeno
  • Patent number: 8194152
    Abstract: Methods for estimating illumination parameters under flickering lighting conditions are disclosed. Illumination parameters, such as phase and contrast, of a intensity-varying light source may be estimated by capturing a sequence of video images, either prior to or after a desired still image to be processed. The relative average light intensities of the adjacently-captured images are calculated and used to estimate the illumination parameters applicable to the desired still image. The estimated illumination parameters may be used to calculate the point spread function of a still image for image de-blurring processing. The estimated illumination parameters may also be used to synchronize the exposure timing of a still image to the time when there is the most light, as well as for use in motion estimation during view/video modes.
    Type: Grant
    Filed: July 29, 2009
    Date of Patent: June 5, 2012
    Assignee: CSR Technology, Inc.
    Inventors: Victor Pinto, Artemy Baxansky, Meir Tzur
  • Patent number: 8189070
    Abstract: Several methods and apparatuses for implementing automatic exposure mechanisms for image capturing devices are described. In one embodiment, an automatic exposure mechanism can use data from a light meter of an image capturing device to determine a metered exposure value associated with incident light. The automatic exposure mechanism can determine a rule based exposure value based on a predetermined rule and exposure settings (e.g., a predetermined light sensitivity of a capture media and a predetermined f-number of the image capturing device). The automatic exposure mechanisms can select either the metered exposure value or the rule based exposure value to set an exposure setting for the image capturing device.
    Type: Grant
    Filed: June 5, 2009
    Date of Patent: May 29, 2012
    Assignee: Apple Inc.
    Inventors: Ralph Brunner, Monique Perez Relova
  • Patent number: 8169503
    Abstract: It is determined whether or not flicker has occurred in an image signal obtained on the basis of an output signal of an image pickup element. If it is determined that flicker has occurred, a flicker correction method is selected according to a gain value set in the image signal.
    Type: Grant
    Filed: September 30, 2008
    Date of Patent: May 1, 2012
    Assignee: Canon Kabushiki Kaisha
    Inventor: Muneyoshi Maeda
  • Patent number: 8149291
    Abstract: An image capture apparatus sets an amount of exposure on an image sensor based on luminance information on an object field, calculates an expected signal level value that is an expected value of luminance signal level that is expected to be output from the image sensor when the image sensor is exposed at the set amount of exposure, compares the expected signal level value with an actual signal level value that is an actual value of luminance signal level output from the image sensor when the image sensor is exposed at the set amount of exposure, and sets a gain based on a result of the comparison.
    Type: Grant
    Filed: May 6, 2005
    Date of Patent: April 3, 2012
    Assignee: Canon Kabushiki Kaisha
    Inventor: Kenji Kyuma
  • Patent number: 8130280
    Abstract: An electronic camera includes: an imaging device that captures a subject image and outputs image signals; an image synthesizing device that performs image synthesis to generate a single image by using a plurality of sets of image signals obtained on different imaging conditions by the imaging device; and a control device that determines whether or not to perform the image synthesis with the image synthesizing device based on a predetermined determination condition, and, when it is determined to perform the image synthesis, controls the image synthesizing device so as to perform the image synthesis.
    Type: Grant
    Filed: September 22, 2008
    Date of Patent: March 6, 2012
    Assignee: Nikon Corporation
    Inventors: Kazuharu Imafuji, Toshiharu Matsuda, Kimio Uematsu
  • Patent number: 8115828
    Abstract: An image processing apparatus includes: an integrating unit integrating an input image signal over a time interval equal to one horizontal period or longer; a normalizing unit normalizing an integrated value obtained by the integrating unit, or a difference value in the integrated value between adjacent fields or frames; an extracting unit extracting a spectrum of the normalized integrated value or difference value; an estimating unit estimating a flicker component on a field-by-field basis or frame-by-frame basis from the extracted spectrum; a detecting unit detecting a deviation of the latest flicker component, from the estimated latest flicker component and one or more flicker components estimated in the past; a correcting unit correcting the latest flicker component on the basis of the detected deviation of the flicker component; and a computing unit computing a corrected flicker component and the input image signal so as to cancel out the corrected flicker component.
    Type: Grant
    Filed: February 27, 2009
    Date of Patent: February 14, 2012
    Assignee: Sony Corporation
    Inventor: Masanori Mikami
  • Publication number: 20120002074
    Abstract: An apparatus and a method which enable effective removal of flicker are provided. Under an illumination environment such as a fluorescent lamp with luminance variation, flicker that occurs in images shot with an X-Y address scanning type imaging device such as a CMOS is effectively removed or reduced. The integral value of the row-by-row signal intensity of an image to be corrected from which to remove flicker is calculated, and this integral value is used to detect flicker components contained in individual rows of an image frame. The detected flicker components represent data according to the actual flicker waveform of the illumination, and a correction process is executed using flicker correction coefficients formed by an anti-phase pattern of the flicker components. Effective flicker removal becomes possible through this process.
    Type: Application
    Filed: January 5, 2011
    Publication date: January 5, 2012
    Inventors: Shigeyuki Baba, Shinichi Yoshimura
  • Patent number: 8040393
    Abstract: A plurality of flicker detection frames are formed by dividing an image into a plurality of frames. A flicker detection circuit performs detection of luminance data for each of the flicker detection frames. The differences between the luminance data of the preceding frame and the current frame, and between the luminance data of the current frame and the following frame with respect to each of the flicker detection frames are taken, a flicker component is extracted, and the flicker frequency is calculated, by a flicker frequency determination program in a microcomputer. Then, the space between the flicker detection frames in which a crest or trough of the extracted flicker component appears is measured, and the results are converted into the flicker frequency. The frame rate of the image pickup signals is controlled so as not to be synchronized with the flicker frequency.
    Type: Grant
    Filed: March 19, 2007
    Date of Patent: October 18, 2011
    Assignee: Sony Corporation
    Inventors: Katsumi Katoh, Eiji Machishima, Toshiaki Kodake
  • Patent number: 8040423
    Abstract: An image-pickup apparatus for picking up an image using a solid-state image pickup device.
    Type: Grant
    Filed: August 2, 2005
    Date of Patent: October 18, 2011
    Assignee: Sony Corporation
    Inventor: Yutaka Sato
  • Patent number: 8031237
    Abstract: A technique of acquiring a width obtaining an appropriate exposure with minimum restrictions, while accurately correcting flickering is provided. An exposure control method includes integrating a video signal obtained by shooting a subject by means of a CMOS imaging element as input video signal over not less than a horizontal period, normalizing the integral value or the difference value of the integral value between neighboring fields or frames, extracting the integral value or the difference value after the normalization as flicker spectrum, determining, based on the extracted flicker spectrum, the presence or absence of a flicker component contained in the video signal obtained by the imaging element and controlling the exposure value, using a program diagram for preferentially employing the shutter speed less liable to produce flickering when it is determined that the video signal contains a flicker component.
    Type: Grant
    Filed: August 24, 2006
    Date of Patent: October 4, 2011
    Assignee: Sony Corporation
    Inventor: Tsukasa Kirisawa
  • Patent number: 8004578
    Abstract: To automatically detect and correct flickers in a video capture device, a frame number generator receives a plurality of frames and generates frame numbers. A storage device stores brightness values of partial pixels of a frame numbered 1. An extractor extracts brightness values of partial pixels of a frame numbered N. A difference summation device computes differences of the brightness values of the partial pixels of the frames numbered 1 and numbered N and sums up the differences to generate a brightness difference summation signal. A flicker detector detects a banding value in the brightness difference summation signal. A flicker corrector uses the banding value and the frame numbers to find a fixed frequency flicker effect in the frames, and generates a flicker correction signal when the fixed frequency flicker effect in the frames is found.
    Type: Grant
    Filed: May 28, 2008
    Date of Patent: August 23, 2011
    Assignee: Sunplus mMedia Inc.
    Inventor: Kun-Yuan Chao
  • Patent number: 8004575
    Abstract: Methods and systems for automatically detecting the presence or absence of a bright object in the field of view of a video camera and/or for adaptively modifying video camera exposure level. A video camera system may be configured to enter and exit an adaptive exposure modification mode upon detection of the presence of a bright object in the field of view of a video camera.
    Type: Grant
    Filed: May 3, 2006
    Date of Patent: August 23, 2011
    Assignee: UTC Fire & Security Americas Corporation, Inc.
    Inventors: Joseph M. Justiss, Michael J. Horowitz
  • Patent number: 7995112
    Abstract: An image-processing apparatus includes an integration section to integrate an image signal in more than one unit of horizontal synchronization period; an interpolation section to carry out an interpolation on the basis of integration values output by the integration section in order to generate integration values corresponding to a predetermined number of sampling positions set in advance during at least one period of flickers appearing on a screen under a fluorescent lamp; a normalization section to normalize an integration value output by the interpolation section or to normalize a difference value between integration values output by the interpolation section as integration values for adjacent fields or frames, respectively; a frequency analysis section to extract a spectrum of normalized integration value or difference values output by the normalization section; and a flicker inference section to infer a flicker component from the spectrum extracted by the frequency analysis section.
    Type: Grant
    Filed: June 12, 2006
    Date of Patent: August 9, 2011
    Assignee: Sony Corporation
    Inventors: Masaya Kinoshita, Seijiro Inaba, Keizo Gomi
  • Patent number: 7978240
    Abstract: There is provided an imaging unit: including an image sensor with a number of pixels arranged in a matrix, the pixels having color pixels where color filters are disposed, and white pixels where the color filters are not disposed; a sampling circuit section for sampling pixel signals generated in the image sensor; and a main controller for controlling the image sensor and/or the sampling circuit section to sample the pixel signals generated in the white pixels or the pixel signals generated in the color pixels sequentially in a time-series manner.
    Type: Grant
    Filed: October 2, 2006
    Date of Patent: July 12, 2011
    Assignee: Konica Minolta Photo Imaging, Inc.
    Inventors: Toshihito Kido, Jun Minakuti, Haruki Nakayama, Dai Shintani, Tsutomu Honda
  • Patent number: 7965323
    Abstract: A circuit includes a luminance average value output unit for extracting luminance values from pixel data of the first and the second frames to generate first luminance average values for pixel lines of the first frame and second luminance average values for pixel lines of the second frame, a flicker curve generating unit for subtracting the second luminance average values from the first luminance average values, thereby generating a flicker curve, and a flicker detecting unit for extracting a plurality of local minimum points from the flicker curve, calculating a distance between each two neighboring local minimum points of the extracted local minimum points, and determining whether the flicker is present based on the distances and the frequency numbers of the distances.
    Type: Grant
    Filed: December 21, 2006
    Date of Patent: June 21, 2011
    Assignee: Crosstek Capital, LLC
    Inventors: Pyeong-Woo Lee, Chae-Sung Kim, Jeong-Guk Lee
  • Patent number: 7920175
    Abstract: An object of this invention is to suppress both the influence of a change in image quality by flicker and the influence of degradation of the image quality by a camera shake when an electronic still camera takes a picture under illumination having flicker. In an electronic still camera which captures a plurality of low-luminance images and composites them into one image of correct exposure, when the exposure time is shorter than the flicker interval of illumination light, the center of the exposure time is made to substantially coincide with the maximum value of the light quantity of illumination light. When the exposure time is longer than the flicker interval of illumination light, the exposure time is set again to a natural number multiple of the flicker interval.
    Type: Grant
    Filed: January 13, 2006
    Date of Patent: April 5, 2011
    Assignee: Canon Kabushiki Kaisha
    Inventor: Masahiro Kawarada
  • Patent number: 7911502
    Abstract: A digital camera includes an image pickup device; a focal plane shutter including a shutter leading curtain and a shutter trailing curtain; a timer for measuring exposure time; a shutter controller which commences measurement of an exposure time when the shutter leading curtain starts traveling, and drives the shutter trailing curtain upon completing the exposure time measurement; and a charge readout controller which reads out electric charges accumulated by the image pickup device during the exposure time at least twice, first before the shutter trailing curtain commences traveling upon the shutter leading curtain commencing traveling and second upon the shutter trailing curtain commencing traveling. The charge readout controller carries out the electric charge readout, before the shutter trailing curtain commences traveling, at a scanning speed in synchronization with a travel speed of the shutter leading curtain in a same direction of the traveling shutter leading curtain.
    Type: Grant
    Filed: October 1, 2007
    Date of Patent: March 22, 2011
    Assignee: Hoya Corporation
    Inventor: Shinichi Suzuki
  • Patent number: 7893974
    Abstract: An information processing apparatus for correcting chromatic aberration of video data, includes a white saturation pixel detecting unit for detecting a white saturation pixel having white saturation using a G signal of the video data composed of an RGB signal, a spatial signal processing unit for performing a spatial signal process on the RGB signal across a plurality of lines, a color signal generating unit for generating a color signal from the RGB signal processed by the spatial signal processing unit, a white saturation distribution information generating unit for generating white saturation distribution information representing a distribution of the white saturation pixels detected by the white saturation pixel detecting unit, and a chromatic aberration correcting unit for correcting a chromatic aberration of the color signal generated by the color signal generating unit, using the white saturation distribution information generated by the white saturation distribution information generating unit.
    Type: Grant
    Filed: October 26, 2006
    Date of Patent: February 22, 2011
    Assignee: Sony Corporation
    Inventor: Takuya Chiba
  • Patent number: 7839440
    Abstract: There is provided an imaging unit: including an image sensor with a number of pixels arranged in a matrix, the pixels having color pixels where color filters are disposed, and white pixels where the color filters are not disposed; a sampling circuit section for sampling pixel signals generated in the image sensor; and a main controller for controlling the image sensor and/or the sampling circuit section to sample the pixel signals generated in the white pixels or the pixel signals generated in the color pixels sequentially in a time-series manner.
    Type: Grant
    Filed: October 2, 2006
    Date of Patent: November 23, 2010
    Assignee: Konica Minolta Photo Imaging, Inc.
    Inventors: Toshihito Kido, Jun Minakuti, Haruki Nakayama, Dai Shintani, Tsutomu Honda
  • Patent number: 7796164
    Abstract: There is provided a signal reading apparatus that reads an output signal from a solid-state image sensing device. The apparatus includes a plurality of measuring means that respectively measures pixel data included in the output signal from the solid-state image sensing device and a timing generator that generates a clock signal showing a timing at which each of the plurality of measuring means measures the pixel data from the solid-state image sensing device and respectively supplies the clock signal to the plurality of measuring means in order to make the plurality of measuring means sequentially measure the pixel data from the solid-state image sensing device by means of an interleaving operation.
    Type: Grant
    Filed: December 12, 2006
    Date of Patent: September 14, 2010
    Assignee: Advantest Corporation
    Inventor: Hiroki Kimura
  • Patent number: 7750950
    Abstract: An image combined high sensitivity image and low sensitivity image is provided with well-adjusted white balance and broad dynamic range. The image is obtained by multiplying the combined data by total gain that depends on scene. A white balance is adjusted with gain value calculated from of high output image data. Lv value representing luminance is calculated and compared with a threshold to decide whether or not the high sensitivity image and the low sensitivity image should be combined. First gamma correction unit performs gamma-correction for the image signal derived from the high sensitivity signal with first gamma character, second gamma correction unit performs gamma-correction for the image signal derived from the low sensitivity signal with second gamma character that is different from the first gamma character, and addition unit combines the image signal from the first gamma correction unit and the image signal from the second gamma correction unit.
    Type: Grant
    Filed: November 30, 2006
    Date of Patent: July 6, 2010
    Assignee: Fujifilm Corporation
    Inventors: Masaya Tamaru, Koichi Sakamoto, Koji Ichikawa, Masahiko Sugimoto, Manabu Hyodo, Kazuhiko Takemura, Hirokazu Kobayashi
  • Patent number: 7679654
    Abstract: An image sensor comprising a number of light sensor circuits each representing a unit pixel and capable of outputting a sensor signal corresponding to a photo current produced in a photoelectric converting element in proportion to light falling thereon, which is provided with a way of detecting a period and a phase of flicker in light from a light source and a way of determining timing of obtaining the maximum brightness of the light source based on the flicker detection signal and reading sensor signals from respective pixels at the timing determined. This image sensor can easily prevent the effect of flicker resulting from flicker of the light source to an image taken and displayed by the image sensor with no need for adjusting the time of accumulating a charge in the capacitor in accord with incident light thereon and compensating an image signal to be displayed.
    Type: Grant
    Filed: March 7, 2005
    Date of Patent: March 16, 2010
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventor: Sukeyuki Shinotsuka
  • Patent number: 7679655
    Abstract: An image-data processing apparatus corrects flicker in each image-data frame. The apparatus includes a threshold generator that generates a threshold; an integrator that integrates values of extracted pixel data of a selected range in each frame on the basis of the threshold; a storage unit that stores integrated values of frames; an average calculator that calculates an average value of the image data on the basis of the integrated values; a gain calculator that divides the average value by an integrated value associated with a target frame, thereby calculating a reference correction gain; a comparator that checks whether pixel data in the target frame are in the selected range; a correction-gain output unit that outputs a correction gain on the basis of the comparison; and a corrector that corrects each piece of the pixel data in the selected range on the basis of the correction gain.
    Type: Grant
    Filed: September 5, 2007
    Date of Patent: March 16, 2010
    Assignee: Sony Corporation
    Inventors: Kazuhiro Sugeno, Koji Kamiya, Seiji Sato
  • Patent number: 7675552
    Abstract: Even in case the shutter speed is high, a flicker can be corrected accurately. A flicker correction method in which a flicker is corrected by predicting, from a present input frame image, a flicker component in an image of a next frame and adding a correction value to the next frame image on the basis of the predicted flicker component includes holding a plurality of flicker data, calculating the correction value by combining a plurality of flicker data together at a ratio set correspondingly to a shutter speed and frame rate, and adding the calculated correction value to the input image signal.
    Type: Grant
    Filed: March 15, 2006
    Date of Patent: March 9, 2010
    Assignee: Sony Corporation
    Inventors: Noriyuki Ono, Motohiro Nakasuji, Yoshiaki Nishide, Hiromasa Ikeyama
  • Patent number: 7663669
    Abstract: An imaging apparatus includes an integrating unit to integrate pixel values of pixels in each of a plurality of areas of an image; a holding unit to hold integration values generated by the integrating unit; an operating unit to operate a waveform of a differential value between integration values of the same areas in two images having a phase difference of flicker of 180 degrees; an extracting unit to extract phase and amplitude of the flicker on the basis of the waveform operated by the operating unit; a selecting unit to select a waveform of the flicker on the basis of shutter speed of the imaging apparatus; and a correcting unit configured to correct the pixel values of the pixels by using a correction value based on the flicker waveform selected by the selecting unit and the phase and amplitude extracted by the extracting unit.
    Type: Grant
    Filed: December 12, 2006
    Date of Patent: February 16, 2010
    Assignee: Sony Corporation
    Inventor: Hidenori Kushida
  • Patent number: 7656431
    Abstract: A video signal processing apparatus that reduces the degree of occurrences of false colors and of differing line concentration by performing knee processing properly, thereby providing desirable video signals. In the apparatus, at the occasion of generating luminance signals and color differences based on the result of knee processing, it is possible to properly generate a luminance signal which is derived from the addition result of pixels which are next to each other and generate a color difference signal which is derived from a difference of the pixels next to each other, achieved by performing the knee processing while keeping the signal level ratio at least between the pixels next to each other on video signals made up of color components arranged on a pixel by pixel basis. In this way, it is possible to keep a balance in hue of a color signal even after being subjected to knee processing.
    Type: Grant
    Filed: March 26, 2003
    Date of Patent: February 2, 2010
    Assignee: Panasonic Corporation
    Inventors: Masayuki Serizawa, Kenji Tabei
  • Patent number: 7656437
    Abstract: An apparatus and a method for efficiently executing correction of false color, such as purple fringe, caused by chromatic aberration and for generating and outputting high-quality image data are provided. A white-saturated pixel is detected from image data, a false-color-pixel detection area is set around the detected white-saturated pixel, and pixels having color corresponding to false color such as purple fringe are detected from the set area. The detected pixels are determined as false-color pixels and correction processing based on the values of the surrounding pixels is performed on the determined false-color pixels. With this configuration, an area of false color such as purple fringe generated in the neighborhood of a white-saturated pixel can be efficiently detected, pixel values can be partially corrected, and high-quality image data can be generated and output without affecting the entire image.
    Type: Grant
    Filed: April 25, 2005
    Date of Patent: February 2, 2010
    Assignee: Sony Corporation
    Inventors: Rui Yamada, Mitsuharu Ohki
  • Patent number: 7646412
    Abstract: A dc level control method for holding a dc level of a clamp portion in an electric signal to be a prescribed value is disclosed, wherein the method comprises the steps of: comparing a dc level of a sampling interval in said electric signal with a predetermined reference value to obtain a difference between said dc level and said reference value using an A/D converting section for dc level comparison which has a lower bit resolution than an A/D converting section for digital signal processing of said electric signal; and feeding back a clamp signal to said electric signal so that said obtained difference between said dc level and said reference value substantially becomes zero. This method is suitable for applying to a signal processing system for a solid state imaging apparatus.
    Type: Grant
    Filed: June 11, 2007
    Date of Patent: January 12, 2010
    Assignee: Sony Corporation
    Inventors: Yasuaki Hisamatsu, Tsutomu Haruta, Ken Koseki
  • Patent number: 7639285
    Abstract: It is now possible to correct flicker without the risk of correcting flicker by error if a moving subject exists in the scene by using values detected in the past in order to prevent degradation of image quality from taking place. The integral value obtained by integrating an input video signal that includes a flicker component over not less than a horizontal period and the difference value between integral values of adjacent fields or frames is normalized. Then, the amplitude component and the phase component of the flicker component are estimated. A flicker coefficient for canceling the amplitude component and the phase component of the flicker component estimated is generated on the basis of the probability of being under the lighting of a fluorescent lamp. The flicker coefficient and the input video signal are computationally determined to obtain a video signal with a reduced flicker component.
    Type: Grant
    Filed: September 7, 2006
    Date of Patent: December 29, 2009
    Assignee: Sony Corporation
    Inventors: Hirofumi Nomura, Masahiro Ito
  • Patent number: 7605359
    Abstract: An apparatus for measuring the power frequency of a light source includes a photo-sensor, a modulator, and a logic unit. The photo-sensor generates an electrical signal that is responsive to light incident thereon from the light source. The modulator generates a modulated signal based on the electrical signal that toggles at a rate substantially proportional to the power frequency of the light source. The logic unit is coupled to receive the modulated signal and determine its toggling frequency.
    Type: Grant
    Filed: September 14, 2007
    Date of Patent: October 20, 2009
    Assignee: OmniVision Technologies, Inc.
    Inventors: Tiejun Dai, Jingzhou Zhang, Liping Deng
  • Patent number: 7598987
    Abstract: A gain control circuit includes a light detector for generating an amount of current based on received light and a first switch for controlling the amount of current from the light detector delivered to a node. The gain control circuit also includes a charge storage element for providing an amount of capacitance to the node and a second switch for controlling the amount of capacitance provided to the node. The gain control circuit further includes an output interface for delivering an output signal based on the amount of current and the amount of capacitance at the node. The light detector may include multiple photodiodes, and the first switch may include a pair of NMOS switching transistors coupled to at least one photodiode. Also, the charge storage element may include multiple capacitors, and the second switch may include a PMOS transistor and an NMOS transistor coupled to each capacitor.
    Type: Grant
    Filed: November 29, 2005
    Date of Patent: October 6, 2009
    Assignee: STMicroelectronics Asia Pacific Pte. Ltd.
    Inventors: Yann Denis Desprez-Le Goarant, Chee Weng Yee
  • Patent number: 7595830
    Abstract: In an imaging device having an all-pixel read mode for reading signals from all pixels and a pixel downsampling read mode for reading signals by appropriately discarding pixels, adjacent ones of pixels use a floating diffusion capacitance, an amplifying transistor, a reset switch and a selection switch in common. In the pixel downsampling read mode, not only a primary capacitance but also a photodiode in each pixel to be discarded are used as capacitances for storing signal charges transferred from transfer switches. This makes it possible to lower the gate voltage of the amplifying transistor as compared with the case of using only the primary capacitance as a capacitance for storing signal charges transferred from a transfer switch to reduce the sensitivity of the pixels, thereby reducing the occurrence of flicker.
    Type: Grant
    Filed: October 27, 2006
    Date of Patent: September 29, 2009
    Assignee: Funai Electric Co., Ltd.
    Inventors: Masaya Oita, Hiromichi Tanaka, Masafumi Kimata
  • Publication number: 20090128660
    Abstract: An apparatus for measuring the power frequency of a light source includes a photo-sensitive transistor, a modulators and a logic unit. The photo-sensitive transistor generates an electrical signal that is responsive to light incident thereon from the light source. The modulator generates a modulated signal based on the electrical signal that toggles at a rate substantially proportional to the power frequency of the light source. The logic unit is coupled to receive the modulated signal and determine its toggling frequency.
    Type: Application
    Filed: November 19, 2007
    Publication date: May 21, 2009
    Applicant: OMNIVISION TECHNOLOGIES, INC.
    Inventors: Tiejun Dai, Sohei Manabe, Hongtao Yao, Jingzhou Zhang, Liping Deng
  • Patent number: 7502054
    Abstract: A method for detecting the presence of flicker in video images includes obtaining luminance data from sampled image fields and analyzing the luminance data to obtain a digital number characterizing the brightness of the luminance data. Frequency analysis is performed on a time-series of digital numbers collected over multiple sampled image fields to provide a signal indicative of the spectral energy at a flicker frequency band and a signal indicative of the spectral energy at a non-flicker frequency band. A ratio of the two spectral energy signals is computed as the flicker detect indicator. Multiple flicker detect indicators are accumulated to generate a flicker present signal. In one embodiment, the flicker detect indicator is accumulated only when the ratio has a value greater than a first threshold and the flicker present signal is asserted only when the number of flicker detect indicator signals accumulated exceeds an entry value.
    Type: Grant
    Filed: December 20, 2004
    Date of Patent: March 10, 2009
    Assignee: PIXIM, Inc.
    Inventors: Paul E. Kalapathy, Michael Frank
  • Patent number: 7489347
    Abstract: A flicker noise detecting method that shortens the time for detecting flicker noise. The method sets two of a plurality of horizontal lines forming a frame as average brightness calculation regions that are separated from each other by the predetermined number of the horizontal lines, calculates an average brightness of the two average brightness calculation regions for each of three frames, multiplies each average brightness by a product sum calculation coefficient, and adds the products to generate a sum and generate a detection signal of flicker noise based on the sum. The product sum calculation coefficient is obtained by plotting one cycle of a sine wave and one cycle of a cosine wave at intervals of ?/3.
    Type: Grant
    Filed: September 20, 2004
    Date of Patent: February 10, 2009
    Assignee: Fujitsu Microelectronics Limited
    Inventors: Hiroshi Daiku, Asao Kokubo
  • Publication number: 20080284870
    Abstract: An image pickup apparatus capable of performing favorable focusing operation when image signals are read out from an image pickup device at a high speed while flickers are occurring. Flickers are detected from image signals outputted from the image pickup device, while the image signals outputted from the image pickup device is stored. The image signals outputted from the image pickup device and the image signals stored in a first memory are synthesized depending on the flicker detection result. A position of a focus lens is adjusted by selectively using any one of the image signals outputted from the image pickup device and the synthesized image signal. When the image pickup device performs reading images in a cycle longer than a flicker cycle, image synthesis is performed depending on the brightness of the image signals outputted from the image pickup device.
    Type: Application
    Filed: May 13, 2008
    Publication date: November 20, 2008
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Takaaki Yokoi
  • Patent number: 7411615
    Abstract: An image pickup apparatus comprises an image pickup unit including a plurality of photoelectric conversion units for picking up an image of an object; and a filter, arranged on the image pickup unit, for reducing a light amount that causes a flicker.
    Type: Grant
    Filed: September 12, 2003
    Date of Patent: August 12, 2008
    Assignee: Canon Kabushiki Kaisha
    Inventor: Seiji Hashimoto
  • Patent number: 7397503
    Abstract: Methods for reducing artifacts caused by illuminant flicker are provided. One such method comprises: providing pixel circuits; and operating the pixel circuits in a bi-directional mode during which first information corresponding to a scene is acquired in forward row-sequential order of the pixel circuits and then second information corresponding to the scene is acquired in a reverse row-sequential order of the pixel circuits. Systems also are provided.
    Type: Grant
    Filed: July 28, 2003
    Date of Patent: July 8, 2008
    Assignee: Micron Technology, Inc.
    Inventors: Richard L. Baer, Ramakrishna Kakarala
  • Patent number: 7307657
    Abstract: In a video signal processing method of processing a luminance signal of a video signal generated by causing a CCD to receive light transmitted through color filters, a control signal yf1 is generated by calculating Cy/Y using a complementary color signal Cy and a luminance signal Y, and coring correction is performed to the luminance signal by using the control signal yf1. The characteristic difference between the color filters is suppressed, and, as a result, flickers are suppressed from being generated.
    Type: Grant
    Filed: March 13, 2003
    Date of Patent: December 11, 2007
    Assignee: Victor Company of Japan, Limited
    Inventor: Hiroyuki Miyahara
  • Patent number: 7298401
    Abstract: Method and apparatus for removing image artifacts from an image of a scene illuminated by a periodically varying light source such as a fluorescent light source. The image is represented by image data, and the method has the steps of determining a flicker function and processing the image data using the flicker function to remove the image artifacts from the image. The method and apparatus operate on data of a single image, do not require any additional input other than values of the flicker and frame periods, and do not require that the flicker be independently monitored. The method and apparatus is suitable for removing image artifacts from an image represented by image data collected by a CMOS image sensor utilizing a rolling shutter.
    Type: Grant
    Filed: August 10, 2001
    Date of Patent: November 20, 2007
    Assignee: Micron Technology, Inc.
    Inventor: Richard L. Baer
  • Patent number: 7289144
    Abstract: A flicker detection apparatus takes in a plurality of images having different shutter times from the image sensing element and judges whether flicker occurs or not based on a variation of flicker components extracted from these images so that the accuracy of flicker detection on picking up a normal image can be improved.
    Type: Grant
    Filed: March 19, 2003
    Date of Patent: October 30, 2007
    Assignee: Seiko Epson Corporation
    Inventor: Shinichi Arazaki
  • Patent number: 7280135
    Abstract: There are provided a pixel array capable of detecting and removing a flicker noise, an image sensor employing the pixel array and an automatic flicker noise detecting method capable of effectively detecting and removing the flicker noise of the image sensor. For the purpose, a pixel array of an image sensor includes a pixel group, having N×M number of unit pixels, for detecting an image signal, N and M being integers, and a pixel column, allocated along a row direction of the pixel group, for detecting an average frequency of a corresponding pixel row to thereby detect the flicker noise.
    Type: Grant
    Filed: July 30, 2003
    Date of Patent: October 9, 2007
    Assignee: Hynix Semiconductor Inc.
    Inventor: Chae-Sung Kim
  • Patent number: 7277127
    Abstract: A method of capturing an image of a scene includes providing an imaging device having an array of pixels. Each pixel is configured to provide a pixel output. The method also includes determining a frequency of light produced by a light source illuminating the scene and capturing an image of the scene using the pixel array. A first capture time for one or more pixels in the array is different from a second capture time of one or more other pixels in the array. The method further includes, for each pixel in the array, determining a relative phase of the light with respect to the capture time of the pixel, determining a compensating gain based on the relative phase of the light and the frequency of the light, and adjusting the pixel output of the pixel in relation to the compensating gain.
    Type: Grant
    Filed: September 9, 2005
    Date of Patent: October 2, 2007
    Assignee: TransChip, Inc.
    Inventors: German Voronov, Eugene Fainstain
  • Patent number: 7248289
    Abstract: A plurality of flicker detection frames are formed by dividing an image into a plurality of frames. A flicker detection circuit performs detection of luminance data for each of the flicker detection frames. The differences between the luminance data of the preceding frame and the current frame, and between the luminance data of the current frame and the following frame with respect to each of the flicker detection frames are taken, a flicker component is extracted, and the flicker frequency is calculated, by a flicker frequency determination program in a microcomputer. Then, the space between the flicker detection frames in which a crest or trough of the extracted flicker component appears is measured, and the results are converted into the flicker frequency. The frame rate of the image pickup signals is controlled so as not to be synchronized with the flicker frequency.
    Type: Grant
    Filed: November 14, 2002
    Date of Patent: July 24, 2007
    Assignee: Sony Corporation
    Inventors: Katsumi Katoh, Eiji Machishima, Toshiaki Kodake
  • Patent number: 7151563
    Abstract: A digital camera has an adjustment value creating part configured to create an adjustment value for adjusting a white balance of an image, and an adjusting part configured to adjust the white balance of the image based on an adjustment value output from the adjustment value creating part. The adjustment value creating part comprises a calculating part configured to calculate a first adjustment value based on image data obtained by taking a subject image, an evaluating part configured to evaluate a reliability of the first adjustment value, an adjustment value correcting part configured to correct the first adjustment value based on input data when the evaluating part evaluates that the reliability of the first adjustment value is low, and create a second adjustment value, and an adjustment value outputting part configured to output the second adjustment value to the adjusting part.
    Type: Grant
    Filed: May 29, 2002
    Date of Patent: December 19, 2006
    Assignee: Olympus Optical Co., Ltd.
    Inventor: Masayu Higuchi
  • Patent number: RE43085
    Abstract: An adaptive color enhancer applies different scale factors to different pixels in a digital image. More color enhancement occurs for bright pixels and for dim pixels than for average-intensity pixels. Also, more color enhancement is applied to the more colorful pixels while less color enhancement is applied to dull, less-colorful pixels. Rather than enhance all pixels to the same extent, the bright, colorful pixels are enhanced further than the average. Likewise, dim areas are color enhanced more than average. A calculation unit receives a YUV pixel. The Y value is compared to range limits and a piece-wise-linear (PWL) function generates an intermediate scale factor. The absolute values of the U and V color values are combined to create a colorfulness factor. The colorfulness factor is also used with a PWL function and the intermediate scale factor to generate a final scale factor for that pixel. The final scale factor is then multiplied by the U and V values of the pixel to generate a color-corrected pixel.
    Type: Grant
    Filed: April 13, 2006
    Date of Patent: January 10, 2012
    Assignee: Faust Communications, LLC
    Inventors: Tao Lin, Tianhua Tang