Patents by Inventor Ramakrishna Kakarala

Ramakrishna Kakarala has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20230087541
    Abstract: A method and apparatus for embedding a digital watermark in image content that is not visible to the human eye is performed on single-sensor digital camera images (often called ‘raw’ images) from a pixel-array. The raw image is transformed to generate preprocessed image coefficients, a watermark message is encrypted using a first key; the encrypted watermark message is randomized using a second key to form a watermark; and the watermark is embedded in randomly selected preprocessed image coefficients.
    Type: Application
    Filed: September 17, 2021
    Publication date: March 23, 2023
    Inventors: Wenshou Chen, Guansong Liu, Boyd Fowler, Ramakrishna Kakarala, Yiyi Ren
  • Patent number: 11144746
    Abstract: A fingerprint sensing apparatus with in-sensor fingerprint enrollment and verification. The sensing apparatus includes a fingerprint sensor configured to generate sensor data in response to user contact with a sensing region and a processing system operable in at least a first mode and a second mode. When operating in the first mode, the processing system is configured to detect a fingerprint of the user based on the sensor data. When operating in the second mode, the processing system is configured to process gesture inputs based on the sensor data. In some implementations, while operating in the second mode, the processing system may selectively authenticate the user based on the gesture inputs and enable the user to enroll or manage fingerprints on the sensing apparatus when the user is authenticated.
    Type: Grant
    Filed: March 17, 2020
    Date of Patent: October 12, 2021
    Assignee: SYNAPTICS INCORPORATED
    Inventors: Kio Kim, Ramakrishna Kakarala, Marcia Tsuchiya
  • Publication number: 20210295012
    Abstract: A fingerprint sensing apparatus with in-sensor fingerprint enrollment and verification. The sensing apparatus includes a fingerprint sensor configured to generate sensor data in response to user contact with a sensing region and a processing system operable in at least a first mode and a second mode. When operating in the first mode, the processing system is configured to detect a fingerprint of the user based on the sensor data. When operating in the second mode, the processing system is configured to process gesture inputs based on the sensor data. In some implementations, while operating in the second mode, the processing system may selectively authenticate the user based on the gesture inputs and enable the user to enroll or manage fingerprints on the sensing apparatus when the user is authenticated.
    Type: Application
    Filed: March 17, 2020
    Publication date: September 23, 2021
    Inventors: Kio KIM, Ramakrishna KAKARALA, Marcia TSUCHIYA
  • Patent number: 9324159
    Abstract: The present invention relates to a method for tracking the motion of a device across a surface. The method repeats the following steps: (a) acquiring, using the device, an input image showing an input area of the surface; (b) comparing the input image to a plurality of current reference images to estimate the displacement between the input image and each current reference image; (c) deciding whether to update each current reference image based on the displacements estimated in step (b), and if said decision is positive, updating the current reference image to form an updated reference image; and (d) determining, based on the displacements, the motion of the device across the surface from an area shown in a previously acquired image to the input area. The previously acquired image may be a previously acquired input image or one of the current reference images.
    Type: Grant
    Filed: July 16, 2012
    Date of Patent: April 26, 2016
    Assignee: Nanyang Technological University
    Inventor: Ramakrishna Kakarala
  • Patent number: 9052759
    Abstract: Embodiments of an apparatus are described. In one embodiment, the apparatus is an optical navigation circuit. In particular, the optical navigation circuit may be part of an optical navigation device. The optical navigation circuit includes an image sensor, dynamic reconfiguration logic, and a digital signal processor. The image sensor includes a pixel array to generate a plurality of electrical signals corresponding to incident light at the pixel array. The dynamic reconfiguration logic is coupled to the image sensor. The dynamic reconfiguration logic is configured to receive the plurality of electrical signals from the pixel array and to generate a plurality of reconfigured electrical signals based on the plurality of electrical signals from the pixel array. The digital signal processor is coupled to the dynamic reconfiguration logic. The digital signal processor is configured to receive the plurality of reconfigured electrical signals from the dynamic reconfiguration logic.
    Type: Grant
    Filed: April 11, 2007
    Date of Patent: June 9, 2015
    Assignee: Avago Technologies General IP (Singapore) Pte. Ltd.
    Inventors: Ramakrishna Kakarala, Annette C. Grot, David W. Dolfi
  • Patent number: 8913232
    Abstract: Two or more spatial filters are used in determining velocity based on speckle translation. A light source may be turned on, turned off, or both for a variable amount of time during operation. The velocity may then be determined with trend identification, correlation, recursive frequency estimation, or measurement bandwidth variation. A confidence level may also be calculated for the measured velocity, and the measured velocity reported or used only when the calculated confidence level meets or exceeds a given value.
    Type: Grant
    Filed: November 23, 2009
    Date of Patent: December 16, 2014
    Assignee: Avago Technologies General IP (Singapore) Pte. Ltd.
    Inventors: Susan Hunter, Charles D. Hoke, Ramakrishna Kakarala, John S. Wenstrand
  • Publication number: 20140161320
    Abstract: The present invention relates to a method for tracking the motion of a device across a surface. The method repeats the following steps: (a) acquiring, using the device, an input image showing an input area of the surface; (b) comparing the input image to a plurality of current reference images to estimate the displacement between the input image and each current reference image; (c) deciding whether to update each current reference image based on the displacements estimated in step (b), and if said decision is positive, updating the current reference image to form an updated reference image; and (d) determining, based on the displacements, the motion of the device across the surface from an area shown in a previously acquired image to the input area. The previously acquired image may be a previously acquired input image or one of the current reference images.
    Type: Application
    Filed: July 16, 2012
    Publication date: June 12, 2014
    Applicant: Nanyang Technological University
    Inventor: Ramakrishna Kakarala
  • Patent number: 8279179
    Abstract: An a data input system includes an encoded pad having position encoding and a data input device adapted to image a portion of the encoded pad to determine position and orientation of the data input device relative to the encoded pad. The encoding pad includes a plurality of correlation windows. Each correlation window includes a primary encoding marker in form of vertical line segment and a set of secondary encoding markers in form of diagonal line segments, at least one diagonal line segment intersecting the vertical line segment at an intersection angle. Spacing of the diagonal line segments encodes the X-axis position of the input device relative to the encoding pad. Intersection angle encodes the Y-axis position of the input device relative to the encoding pad. Angle of the primary encoding marker vertical line segment within the frame of the captured image encodes the angular orientation of the input device relative to the axes of the encoded pad.
    Type: Grant
    Filed: June 3, 2009
    Date of Patent: October 2, 2012
    Assignee: Avago Technologies ECBU IP (Singapore) Pte. Ltd.
    Inventors: Richard L. Baer, Ramakrishna Kakarala, Dietrich W. Vook, Xuemei Zhang, Izhak Baharav, Paul L. Corredoura
  • Patent number: 8264461
    Abstract: An apparatus for controlling the position of a screen pointer includes an at least partially coherent light source for illuminating an imaging surface, thereby generating reflected images. The apparatus includes a navigation sensor for generating digital images based on the reflected images, performing a movement computation based on the digital images, generating movement data based on the movement computation that is indicative of relative motion between the imaging surface and the apparatus, wherein the movement computation has a low sensitivity to effects in the digital images caused by particle contamination.
    Type: Grant
    Filed: April 1, 2008
    Date of Patent: September 11, 2012
    Assignee: Avago Technologies ECBU IP (Singapore) Pte. Ltd.
    Inventors: Michael J. Brosnan, Ramakrishna Kakarala, Roopinder Singh Grewal, Mark M. Butterworth, Vincent C. Moyer, Tong Xie, Marshall T. Depue
  • Patent number: 7974489
    Abstract: An optical imaging system with dynamic buffer management is described. Embodiments of the optical imaging system include an image sensor, a buffer, and a buffer mode controller. The image sensor includes a pixel array to read out a plurality of pixel lines for a frame of an image. The buffer is configured to store a plurality of buffer values corresponding to a plurality of pixel values for each of the pixel lines. The buffer mode controller is configured to dynamically switch between an accumulation mode and an averaging mode. The accumulation mode facilitates a computation of each buffer value according to a sum value of the corresponding pixel value and a corresponding previous buffer value. The averaging mode facilitates a computation of each buffer value according to an average value of a normalized value of the corresponding pixel value and the corresponding previous buffer value.
    Type: Grant
    Filed: May 30, 2007
    Date of Patent: July 5, 2011
    Assignee: Avago Technologies ECBU IP (Singapore) Pte. Ltd.
    Inventors: Ramakrishna Kakarala, Alexander C. Schneider
  • Patent number: 7969410
    Abstract: Apparatus and method of optically detecting click events are described. Images of a contact surface are captured at respective capture times. The captured images are convolved with a two-dimensional circularly symmetric spatial bandpass filter to produce corresponding filtered images each including a set of pixels with respective pixel value magnitudes. Based on the pixel value magnitudes of the corresponding filtered images, each of the capture times is assigned to one of an in-contact time class during which the contact surface is determined to be in-contact with a user's finger and an out-of-contact time class during which the contact surface is determined to be out-of-contact with the user's finger. A select signal indicating that the contact surface has been touched to make a selection is generated based on a click event predicate defining at least one condition on the time classes respectively assigned to successive ones of the capture times.
    Type: Grant
    Filed: August 23, 2006
    Date of Patent: June 28, 2011
    Assignee: Avago Technologies General IP (Singapore) Pte. Ltd.
    Inventor: Ramakrishna Kakarala
  • Patent number: 7737947
    Abstract: A system, method, and device for tracking motion across a surface by creating an interference pattern by reflecting light from the surface. There is produced, as a result of sensor moving across the surface, at least one signal pattern corresponding to a detection of a dimension of the interference pattern. This detected dimension is associated with an assumed dimensional value to determine a distance traveled by the sensor.
    Type: Grant
    Filed: October 16, 2003
    Date of Patent: June 15, 2010
    Assignee: Avago Technologies ECBU IP (Singapore) Pte. Ltd.
    Inventors: Dale W. Schroeder, Marshall T. DePue, Ramakrishna Kakarala, Tong Xie, Gregory D. VanWiggeren
  • Publication number: 20100066680
    Abstract: Two or more spatial filters are used in determining velocity based on speckle translation. A light source may be turned on, turned off, or both for a variable amount of time during operation. The velocity may then be determined with trend identification, correlation, recursive frequency estimation, or measurement bandwidth variation. A confidence level may also be calculated for the measured velocity, and the measured velocity reported or used only when the calculated confidence level meets or exceeds a given value.
    Type: Application
    Filed: November 23, 2009
    Publication date: March 18, 2010
    Applicant: Avago Technologies General IP (Singapore) Pte. Ltd.
    Inventors: Susan Hunter, Charles D. Hoke, Ramakrishna Kakarala, John S. Wenstrand
  • Patent number: 7646373
    Abstract: Two or more spatial filters are used in determining velocity based on speckle translation. A light source may be turned on, turned off, or both for a variable amount of time during operation. The velocity may then be determined with trend identification, correlation, recursive frequency estimation, or measurement bandwidth variation. A confidence level may also be calculated for the measured velocity, and the measured velocity reported or used only when the calculated confidence level meets or exceeds a given value.
    Type: Grant
    Filed: December 17, 2004
    Date of Patent: January 12, 2010
    Assignee: Avago Technologies General IP (Singapore) Pte. Ltd.
    Inventors: Susan Hunter, Charles D. Hoke, Ramakrishna Kakarala, John S. Wenstrand
  • Patent number: 7613329
    Abstract: An apparatus for controlling the position of a screen pointer includes a light source for illuminating an imaging surface, thereby generating reflected images. The apparatus includes a navigation sensor for generating digital images based on the reflected images, detecting defective pixel locations in the digital images, and generating movement data based on the digital images that is indicative of relative motion between the imaging surface and the apparatus.
    Type: Grant
    Filed: March 8, 2004
    Date of Patent: November 3, 2009
    Assignee: Avago Technologies ECBU IP (Singapore) Pte. Ltd.
    Inventors: Roopinder Singh Grewal, Ramakrishna Kakarala
  • Publication number: 20090237274
    Abstract: An a data input system includes an encoded pad having position encoding and a data input device adapted to image a portion of the encoded pad to determine position and orientation of the data input device relative to the encoded pad. The encoding pad includes a plurality of correlation windows. Each correlation window includes a primary encoding marker in form of vertical line segment and a set of secondary encoding markers in form of diagonal line segments, at least one diagonal line segment intersecting the vertical line segment at an intersection angle. Spacing of the diagonal line segments encodes the X-axis position of the input device relative to the encoding pad. Intersection angle encodes the Y-axis position of the input device relative to the encoding pad. Angle of the primary encoding marker vertical line segment within the frame of the captured image encodes the angular orientation of the input device relative to the axes of the encoded pad.
    Type: Application
    Filed: June 3, 2009
    Publication date: September 24, 2009
    Applicant: AVAGO TECHNOLOGIES ECBU IP (SINGAPORE) PTE. LTD.
    Inventors: Richard L. Baer, Ramakrishna Kakarala, Dietrich W. Vook, Xuemei Zhang, Izhak Baharav, Paul L. Corredoura
  • Patent number: 7567341
    Abstract: A technique for adapting an optical navigation device for navigation on a transparent structure such as a glass plate involves establishing a navigation window for navigation tracking, detecting reflected light within the navigation window, generating an output signal in response to the detected light, and adjusting a characteristic of the navigation window in response to the output signal. An optical navigation device includes an illumination system configured to output light, an image sensor configured to generate an output signal related to a detected portion of the light, and a transparent structure adapter module configured to adjust a navigation window of the image sensor in response to the output signal to adapt the optical navigation device for use directly on an opaque surface or for use on a transparent structure that is located between the optical navigation device and the opaque surface.
    Type: Grant
    Filed: September 28, 2007
    Date of Patent: July 28, 2009
    Assignee: Avago Technologies ECBU IP (Singapore) Pte. ltd.
    Inventors: David W. Dolfi, Ramakrishna Kakarala, Annette Claire Grot
  • Patent number: 7557799
    Abstract: An a data input system includes an encoded pad having position encoding and a data input device adapted to image a portion of the encoded pad to determine position and orientation of the data input device relative to the encoded pad. The encoding pad includes a plurality of correlation windows. Each correlation window includes a primary encoding marker in form of vertical line segment and a set of secondary encoding markers in form of diagonal line segments, at least one diagonal line segment intersecting the vertical line segment at an intersection angle. Spacing of the diagonal line segments encodes the X-axis position of the input device relative to the encoding pad. Intersection angle encodes the Y-axis position of the input device relative to the encoding pad. Angle of the primary encoding marker vertical line segment within the frame of the captured image encodes the angular orientation of the input device relative to the axes of the encoded pad.
    Type: Grant
    Filed: June 17, 2004
    Date of Patent: July 7, 2009
    Assignee: Avago Technologies ECBU IP (Singapore) Pte. Ltd.
    Inventors: Richard L. Baer, Ramakrishna Kakarala, Dietrich W. Vook, Xuemei Zhang, Izhak Baharav, Paul L. Corredoura
  • Publication number: 20080298696
    Abstract: An optical imaging system with dynamic buffer management is described. Embodiments of the optical imaging system include an image sensor, a buffer, and a buffer mode controller. The image sensor includes a pixel array to read out a plurality of pixel lines for a frame of an image. The buffer is configured to store a plurality of buffer values corresponding to a plurality of pixel values for each of the pixel lines. The buffer mode controller is configured to dynamically switch between an accumulation mode and an averaging mode. The accumulation mode facilitates a computation of each buffer value according to a sum value of the corresponding pixel value and a corresponding previous buffer value. The averaging mode facilitates a computation of each buffer value according to an average value of a normalized value of the corresponding pixel value and the corresponding previous buffer value.
    Type: Application
    Filed: May 30, 2007
    Publication date: December 4, 2008
    Inventors: Ramakrishna Kakarala, Alexander C. Schneider
  • Patent number: 7460688
    Abstract: A digital image sensor comprising an array of pixels and a processor is provided. The array of pixels comprises a current pixel in a first color plane that is configured to produce a current sensor value, a first plurality of pixels in the first color plane that is configured to produce a first plurality of sensor values, and a second plurality of pixels in the second color plane that is configured to produce a second plurality of sensor values. The processor is configured to generate a plurality of estimate values using the first plurality of sensor values and a plurality of intensity ratios associated with the second plurality of sensor values, and the processor is configured to determine whether the current pixel is defective using the plurality of estimate values and the current sensor value.
    Type: Grant
    Filed: December 9, 2004
    Date of Patent: December 2, 2008
    Assignee: Aptina Imaging Corporation
    Inventors: John H. Stanback, Xuemei Zhang, Ramakrishna Kakarala, Bond Yu Pong Ying