Patents by Inventor Anders Johannesson

Anders Johannesson 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).

  • Patent number: 9536154
    Abstract: A method of monitoring a scene by a camera (7) comprises marking a part (14) of the scene with light having a predefined spectral content and a spatial verification pattern. An analysis image is captured of the scene by a sensor sensitive to the predefined spectral content. The analysis image is segmented based on the predefined spectral content, to find a candidate image region. A spatial pattern is detected in the candidate image region, and a characteristic of the detected spatial pattern is compared to a corresponding characteristic of the spatial verification pattern. If the characteristics match, the candidate image region is identified as a verified image region corresponding to the marked part (14) of the scene. Image data representing the scene is obtained, and image data corresponding to the verified image region is processed in a first manner, and remaining image data is processed in a second manner.
    Type: Grant
    Filed: May 8, 2014
    Date of Patent: January 3, 2017
    Assignee: Axis AB
    Inventors: Markus Skans, Anders Johannesson, Jiandan Chen, Joakim Baltsen
  • Patent number: 9438814
    Abstract: The present invention relates to a method (300) for reducing stray light in an output image of a scene, said method comprising; providing (301) a camera (100) comprising a lens assembly (102, 202), providing (302) an aperture unit (103, 203) having an aperture gate (204a, 204b) in an aperture plane being orthogonal to an optical axis (OA) of said lens assembly (102, 202), said aperture gate (204a, 204b) being adjustable in said aperture plane, acquiring (303), by means of said camera (100), a plurality of images of said scene, wherein each image of said plurality of images is acquired using an unique aperture gate setting, wherein each of said unique aperture gate settings correspond to a unique combination of a position and a shape of said aperture gate (204a, 204b) in said aperture plane, analyzing (305) said plurality of images for generating data pertaining to a difference in stray light content with respect to said plurality of images, and producing (306) said output image based on said data pertaining t
    Type: Grant
    Filed: April 24, 2014
    Date of Patent: September 6, 2016
    Assignee: AXIS AB
    Inventors: Jonas Hjelmstrom, Anders Johannesson
  • Patent number: 8982228
    Abstract: An image acquisition device and a method for capturing image data is disclosed. The method comprises exposing an image sensor to light from a scene, selecting substantially all rows of sensor pixels in an image sensor in a substantially random order, starting an exposure period for each row of sensor pixels in the image sensor in the order the rows were selected, buffering the rows of sensor pixels comprised in an image frame until all rows of the image frame have registered image data for the presently captured image frame, and outputting image data representing the image frame by outputting image data from each row of sensor pixels.
    Type: Grant
    Filed: September 26, 2013
    Date of Patent: March 17, 2015
    Assignee: AXIS AB
    Inventors: Per Kannermark, Anders Johannesson
  • Patent number: 8908046
    Abstract: There is provided a method for determining the reliability of a fault detection of a camera in a camera system. According to the method data relating to environmental conditions are received (204) and compared to accessed (202) criteria relating to environmental conditions external to the camera and affecting the reliability of the fault detection test. If the received data complies with the criteria it is determined (206) that the fault detection test gives a reliable result. This is advantageous in that false fault detection tests may be identified.
    Type: Grant
    Filed: April 9, 2014
    Date of Patent: December 9, 2014
    Assignee: Axis AB
    Inventors: Anders Johannesson, Stefan Lundberg, Wilfried Rakow
  • Publication number: 20140340525
    Abstract: There is provided a method for determining the reliability of a fault detection of a camera in a camera system. According to the method data relating to environmental conditions are received (204) and compared to accessed (202) criteria relating to environmental conditions external to the camera and affecting the reliability of the fault detection test. If the received data complies with the criteria it is determined (206) that the fault detection test gives a reliable result. This is advantageous in that false fault detection tests may be identified.
    Type: Application
    Filed: April 9, 2014
    Publication date: November 20, 2014
    Applicant: Axis AB
    Inventors: Anders Johannesson, Stefan Lundberg, Wilfried Rakow
  • Publication number: 20140334676
    Abstract: A method of monitoring a scene by a camera (7) comprises marking a part (14) of the scene with light having a predefined spectral content and a spatial verification pattern. An analysis image is captured of the scene by a sensor sensitive to the predefined spectral content. The analysis image is segmented based on the predefined spectral content, to find a candidate image region. A spatial pattern is detected in the candidate image region, and a characteristic of the detected spatial pattern is compared to a corresponding characteristic of the spatial verification pattern. If the characteristics match, the candidate image region is identified as a verified image region corresponding to the marked part (14) of the scene. Image data representing the scene is obtained, and image data corresponding to the verified image region is processed in a first manner, and remaining image data is processed in a second manner.
    Type: Application
    Filed: May 8, 2014
    Publication date: November 13, 2014
    Applicant: Axis AB
    Inventors: Markus SKANS, Anders Johannesson, Jiandan Chen, Joakim Baltsen
  • Publication number: 20140320686
    Abstract: The present invention relates to a method (300) for reducing stray light in an output image of a scene, said method comprising; providing (301) a camera (100) comprising a lens assembly (102, 202), providing (302) an aperture unit (103, 203) having an aperture gate (204a, 204b) in an aperture plane being orthogonal to an optical axis (OA) of said lens assembly (102, 202), said aperture gate (204a, 204b) being adjustable in said aperture plane, acquiring (303), by means of said camera (100), a plurality of images of said scene, wherein each image of said plurality of images is acquired using an unique aperture gate setting, wherein each of said unique aperture gate settings correspond to a unique combination of a position and a shape of said aperture gate (204a, 204b) in said aperture plane, analyzing (305) said plurality of images for generating data pertaining to a difference in stray light content with respect to said plurality of images, and producing (306) said output image based on said data pertaining t
    Type: Application
    Filed: April 24, 2014
    Publication date: October 30, 2014
    Applicant: Axis AB
    Inventors: Jonas HJELMSTROM, Anders Johannesson
  • Patent number: 8848198
    Abstract: A method for determining a tilt of an image sensor surface plane in a camera in relation to a lens reference plane of the camera includes sending light onto the image sensor, receiving light reflected from the image sensor, identifying an interference pattern in the reflected light, identifying a feature of the interference pattern, and determining the tilt of the image sensor surface plane based on a position of the feature identified in the interference pattern.
    Type: Grant
    Filed: July 19, 2012
    Date of Patent: September 30, 2014
    Assignee: Axis AB
    Inventors: Jonas Hjelmström, Anders Johannesson
  • Publication number: 20140092277
    Abstract: An image acquisition device and a method for capturing image data is disclosed. The method comprises exposing an image sensor to light from a scene, selecting substantially all rows of sensor pixels in an image sensor in a substantially random order, starting an exposure period for each row of sensor pixels in the image sensor in the order the rows were selected, buffering the rows of sensor pixels comprised in an image frame until all rows of the image frame have registered image data for the presently captured image frame, and outputting image data representing the image frame by outputting image data from each row of sensor pixels.
    Type: Application
    Filed: September 26, 2013
    Publication date: April 3, 2014
    Applicant: AXIS AB
    Inventors: Per KANNERMARK, Anders JOHANNESSON
  • Publication number: 20130021617
    Abstract: A method for determining a tilt of an image sensor surface plane in a camera in relation to a lens reference plane of the camera includes sending light onto the image sensor, receiving light reflected from the image sensor, identifying an interference pattern in the reflected light, identifying a feature of the interference pattern, and determining the tilt of the image sensor surface plane based on a position of the feature identified in the interference pattern.
    Type: Application
    Filed: July 19, 2012
    Publication date: January 24, 2013
    Applicant: AXIS AB
    Inventors: Jonas Hjelmström, Anders Johannesson
  • Patent number: 7692700
    Abstract: A method used for the compensation of vignetting in digital cameras has been achieved. The compensation for vignetting is done in two steps. The first step is done during production of the camera unit and involves taking and analyzing an image of a test screen, preferably a gray test screen. This results in a set of e.g. 5×5 coefficients describing a polynomial surface. The second step is done for each image that is taken by the camera and involves calculating and applying a gain-table based on polynomial coefficients to all pixels of the image to compensate vignetting.
    Type: Grant
    Filed: March 4, 2003
    Date of Patent: April 6, 2010
    Assignee: Digital Imaging Systems GmbH
    Inventors: Anders Johannesson, Ingemar Larsson
  • Publication number: 20080165262
    Abstract: A method for reducing smear effect in an image sensor is presented. Firstly, a first charge level value from a first set of covered elements and a second charge level value from a second set of covered elements are received. Secondly, the first and the second charge level values are compared. Thirdly, if a difference resulting from said comparing said first and said second charge level values is outside a predetermined interval, camera settings are adjusted.
    Type: Application
    Filed: November 8, 2007
    Publication date: July 10, 2008
    Applicant: AXIS AB
    Inventors: Per Kannermark, Anders Johannesson, Daniel Anderberg
  • Patent number: 7224833
    Abstract: A method for a fast color saturation control of digital color images using one color saturation factor has been achieved. Said method can be performed in any color space having three primaries as e.g. the R-G-B or in the CMY color space without the requirement to convert all the pixels of said color image into another color space as e.g. HSI to perform the color saturation control. Thus a significant computational effort for the conversion of the pixels from one color space into another and back can be avoided. Saving computational effort saves time and reduces the electrical power consumption. Right after the color saturation control process the corrected images can be viewed, if the colors are not satisfactory the process can be easily repeated using a modified color saturation factor. Said method can be used for new pictures taken by a digital camera as well as for downloaded pictures from any source. Additionally said method of color saturation control can be combined with a color correction process.
    Type: Grant
    Filed: October 15, 2002
    Date of Patent: May 29, 2007
    Assignee: Dialog Imaging Systems GmbH
    Inventors: Anders Johannesson, Ingemar Larsson
  • Patent number: 7158170
    Abstract: A test system and a related method to perform optical and electrical tests, to adjust the focus and to seal the lens of digital fixed-focus cameras have been achieved. Said test system is especially suited for miniature camera module to be built into consumer electronic devices as mobile phones, PDAs, etc. Said test system comprises three parts, a control system, an auto-focus head, and a XYZ robot. Said auto-focus head executes the adjustment of the focus, identifies hot pixels and black level, tests the saturation level, identifies cold pixels, tests dust particles and white, blue, red, and infrared color levels. As last step the auto-focus applies glue to fix the focused lens of the camera module. Said XYZ robot performs is moving the camera modules to be tested in XY direction and is approaching the lens system of the auto-focus head in Z direction. Said control system has interfaces to both, XYZ robot and auto-focus hand and is comprising interfaces and a frame grabber.
    Type: Grant
    Filed: May 8, 2003
    Date of Patent: January 2, 2007
    Assignee: Dialog Imaging Systems GmbH
    Inventors: Lars Gustavsson, Anders Johannesson, Henrik Telander
  • Patent number: 7146040
    Abstract: A method and a system for an automatic white balancing of color images being exposed to different illuminants have been achieved. The color information from the sensor color channels is measured and averaged over all pixels belonging to each of the colors of the color array used. The result is equivalent to what color a 1-pixel camera would see if pointed to the same scene. From this “statistical pixel” the ratios of the colors involved are calculated. Pictures taken in different illuminants as e.g. daylight, fluorescent light or incandescent light can then be separated due to their location in different categories in a space defined by said ratios of the colors involved. Each category has predefined white balance factors, which are applied to the image now.
    Type: Grant
    Filed: October 21, 2002
    Date of Patent: December 5, 2006
    Assignee: Dialog Imaging Systems GmbH
    Inventors: Anders Johannesson, Ingemar Larsson
  • Publication number: 20050018908
    Abstract: A method for compressing a digital image composed of a matrix of pixels to provide a compressed digital representation of said image of a predetermined size, the quality of the compressed digital representation being affected by a compression quality factor Q and the method including the fol-lowing steps: for a particular image producing device, developing a mathematical model defining a relationship between the content of the digital image and Q, developing said mathematical model by repeatedly compressing a set of digital test images with varying Q until each test image is compressed to a predetermined size, determining a metric M representing the content of the digital image, applying said metric M in said mathematical model to obtain an image determined quality factor Qmod and compressing the digital image using said quality factor Qmod.
    Type: Application
    Filed: November 6, 2002
    Publication date: January 27, 2005
    Inventors: Anders Johannesson, Ingemar Larsson
  • Publication number: 20040189812
    Abstract: A test system and a related method to perform optical and electrical tests, to adjust the focus and to seal the lens of digital fixed-focus cameras have been achieved. Said test system is especially suited for miniature camera module to be built into consumer electronic devices as mobile phones, PDAs, etc. Said test system comprises three parts, a control system, an auto-focus head, and a XYZ robot. Said auto-focus head executes the adjustment of the focus, identifies hot pixels and black level, tests the saturation level, identifies cold pixels, tests dust particles and white, blue, red, and infrared color levels. As last step the auto-focus applies glue to fix the focused lens of the camera module. Said XYZ robot performs is moving the camera modules to be tested in XY direction and is approaching the lens system of the auto-focus head in Z direction. Said control system has interfaces to both, XYZ robot and auto-focus hand and is comprising interfaces and a frame grabber.
    Type: Application
    Filed: May 8, 2003
    Publication date: September 30, 2004
    Applicant: Dialog Semiconductor Gmbh
    Inventors: Lars Gustavsson, Anders Johannesson, Henrik Telander
  • Publication number: 20040155970
    Abstract: A method used for the compensation of vignetting in digital cameras has been achieved. The compensation for vignetting is done in two steps. The first step is done during production of the camera unit and involves taking and analyzing an image of a test screen, preferably a gray test screen. This results in a set of e.g. 5×5 coefficients describing a polynomial surface. The second step is done for each image that is taken by the camera and involves calculating and applying a gain-table based on polynomial coefficients to all pixels of the image to compensate vignetting.
    Type: Application
    Filed: March 4, 2003
    Publication date: August 12, 2004
    Applicant: Dialog Semiconductor GmbH
    Inventors: Anders Johannesson, Ingemar Larsson
  • Publication number: 20040057615
    Abstract: A method and a system for an automatic white balancing of color images being exposed to different illuminants have been achieved. The color information from the sensor color channels is measured and averaged over all pixels belonging to each of the colors of the color array used. The result is equivalent to what color a 1-pixel camera would see if pointed to the same scene. From this “statistical pixel” the ratios of the colors involved are calculated. Pictures taken in different illuminants as e.g. daylight, fluorescent light or incandescent light can then be separated due to their location in different categories in a space defined by said ratios of the colors involved. Each category has predefined white balance factors, which are applied to the image now.
    Type: Application
    Filed: October 21, 2002
    Publication date: March 25, 2004
    Applicant: Dialong Semiconductor GmbH.
    Inventors: Anders Johannesson, Ingemar Larsson
  • Publication number: 20040057060
    Abstract: A method for a fast color saturation control of digital color images using one color saturation factor has been achieved. Said method can be performed in any color space having three primaries as e.g. the R-G-B or in the CMY color space without the requirement to convert all the pixels of said color image into another color space as e.g. HSI to perform the color saturation control. Thus a significant computational effort for the conversion of the pixels from one color space into another and back can be avoided. Saving computational effort saves time and reduces the electrical power consumption. Right after the color saturation control process the corrected images can be viewed, if the colors are not satisfactory the process can be easily repeated using a modified color saturation factor. Said method can be used for new pictures taken by a digital camera as well as for downloaded pictures from any source. Additionally said method of color saturation control can be combined with a color correction process.
    Type: Application
    Filed: October 15, 2002
    Publication date: March 25, 2004
    Applicant: Dialog Semiconductor GmbH.
    Inventors: Anders Johannesson, Ingemar Larsson