Patents by Inventor Dan S. Johnson

Dan S. Johnson 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: 7072081
    Abstract: The present invention provides a compact, portable system for capturing two dimensional images from printed and related media, as well as three dimensional scenic images, such as photographs, combining the optical features of scanning and photography. A compact, portable image capturing system is provided that is relatively simple and inexpensive, which is easy to operate, rugged, reliable, integrating the navigational and text-gathering functionalities seamlessly, transparently, and reliably, and not prone to optical misalignment, or cessation of scanning and loss of information, obviating much of the repetition of scanning efforts required by the conventional art. The present invention provides a compact, portable system for capturing both two dimensional images from printed and related media, and three dimensional scenic images, such as photographs, while providing constant user feedback of the image quality and effectiveness, during the imaging process.
    Type: Grant
    Filed: October 24, 2001
    Date of Patent: July 4, 2006
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Dan S. Johnson, Shaz Naqvi
  • Patent number: 6567570
    Abstract: An image scanner uses optical targets within the scanner to characterize imperfections of a lens system and to partially compensate for the imperfections using digital image processing. In one sample embodiment, a series of two-dimensional optical targets are placed outside the document scanning area. Each individual target is suitable for obtaining an estimate of the point-spread function for a small segment of the scan line. Each point-spread function is then used to compute a convolution kernel for the corresponding segment of the scan line. Alternatively, each point-spread function may be used in an iterative solution for a modified image. In an alternative embodiment, a two-dimensional known random pattern is provided for a target. Cross-correlation of a portion of the known random pattern with the scanned image of the same portion of known random pattern provides an estimate of the point-spread function for the portion of the scan line corresponding to the portion of the known random pattern.
    Type: Grant
    Filed: October 30, 1998
    Date of Patent: May 20, 2003
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Michael J. Steinle, Dan S. Johnson
  • Publication number: 20030076546
    Abstract: The present invention provides a compact, portable system for capturing two dimensional images from printed and related media, as well as three dimensional scenic images, such as photographs, combining the optical features of scanning and photography. A compact, portable image capturing system is provided that is relatively simple and inexpensive, which is easy to operate, rugged, reliable, integrating the navigational and text-gathering functionalities seamlessly, transparently, and reliably, and not prone to optical misalignment, or cessation of scanning and loss of information, obviating much of the repetition of scanning efforts required by the conventional art. The present invention provides a compact, portable system for capturing both two dimensional images from printed and related media, and three dimensional scenic images, such as photographs, while providing constant user feedback of the image quality and effectiveness, during the imaging process.
    Type: Application
    Filed: October 24, 2001
    Publication date: April 24, 2003
    Inventors: Dan S. Johnson, Shaz Naqvi
  • Patent number: 6542260
    Abstract: A multiple image scanner that performs a single scan of a document containing different types of images (e.g., text and graphics) and sends multiple renditions of the same document from the scanner to a host computer (e.g., one high resolution gray scale image and one low resolution high bit depth color image; or one high resolution, low bit depth gray scale or monochrome image and one low resolution, high bit depth gray scale or monochrome image; or one high resolution, low bit depth color image and one low resolution, high bit depth color image), thus greatly reducing the total amount of data sent to and processed by the host computer.
    Type: Grant
    Filed: October 28, 1997
    Date of Patent: April 1, 2003
    Assignee: Hewlett-Packard Company
    Inventors: Robert G. Gann, Steven L. Webb, Greg A. Degi, Gregory A. Brake, Kevin J. Youngers, Dan S. Johnson
  • Patent number: 6172772
    Abstract: A process for compensation for real time changes of magnification in an optics system for an image scanner. Targets having high-contrast edges, on both sides of an image to be scanned, are scanned along with the image. If magnification changes, the number of pixels between the targets may change. The pixels between the targets are filtered to generate a fixed number of pixels. Photosensor sensitivity compensation values may be separated into factory compensation values and scanner pre-scan compensation values. Factory compensation values are applied before filtering. Differences between factory compensation values and pre-scan compensation values are applied after filtering.
    Type: Grant
    Filed: July 31, 1998
    Date of Patent: January 9, 2001
    Assignee: Hewlett-Packard Company
    Inventors: Michael J. Steinle, Dan S. Johnson
  • Patent number: 6160249
    Abstract: A method of adjusting the resolution of a scan based on the scan area or the scan window size. The smaller the scan window size, the higher the scan resolution would be. The final scan resolution is a function of an initial resolution, a resolution modifier, a printer factor, and an image factor. The resolution modifier, the printer factor and the image factor are dependent on the scan window size, the system printer, and the scan image type respectively.
    Type: Grant
    Filed: October 8, 1998
    Date of Patent: December 12, 2000
    Assignee: Hewlett-Packard Company
    Inventors: Steven L. Webb, Dan S. Johnson
  • Patent number: 6148117
    Abstract: A method for image processing combining a device-specific image processing kernel operation with a general image processing kernel operation. Device specific parameters are sent from a host computer to an imaging device. The imaging device selects appropriate device-specific convolution coefficients. The host computer selects additional kernel operations. In a first example embodiment, the device-specific coefficients are then uploaded to the host computer and the host computer convolves the host-specified operations with the device-specific operations. The combined kernel is then downloaded to the imaging device. In an alternative embodiment, the host-specified operations are downloaded to the imaging device for combining. The combined kernels are then used by the imaging device for convolution operations on an image. As a result, host computer software can modify a kernel operation within an imaging device with minimal knowledge of device-specific parameters such as native resolution.
    Type: Grant
    Filed: December 27, 1996
    Date of Patent: November 14, 2000
    Assignee: Hewlett-Packard Company
    Inventors: Patricia D. Lopez, Dan S. Johnson, Nancy K. Mundelius
  • Patent number: 5920407
    Abstract: An imaging system for applying separate color tonemaps comprises an optical scanning assembly configured to scan an object and produce image data having a first resolution that corresponds to a color characteristic. A memory device associated with the imaging system stores a look-up table that corresponds to a predetermined transfer function. An image data processor operatively associated with the memory device and the optical scanning assembly alters the resolution of the image data having the first resolution to produce image data having a second resolution, the second resolution being less than the first resolution, and also applies the image data having the second resolution to the look-up table to look up LowPoint image data having a third resolution, the third resolution being greater than the second resolution.
    Type: Grant
    Filed: January 9, 1997
    Date of Patent: July 6, 1999
    Assignee: Hewlett-Packard Company
    Inventors: Michael D Erickson, Dan S Johnson
  • Patent number: 5483053
    Abstract: A method of scanning an object at a predetermined resolution along the scanning direction with color scanner apparatus having M linear photosensors positioned in parallel, spaced-apart relation and being exposed for a predetermined exposure time, may comprise the steps of calculating an exposure delay time for each of (M-1) slave linear photosensors. Then, at a start scan time, a master linear photosensor is exposed to light from the illuminated scan line for the predetermined exposure time. However, the slave linear photosensors are not necessarily exposed at the start scan time. Instead, the first exposure for each of the slave linear photosensors is delayed for a time equivalent to the exposure delay time calculated for each respective slave linear photosensor.
    Type: Grant
    Filed: September 27, 1994
    Date of Patent: January 9, 1996
    Assignee: Hewlett-Packard Company
    Inventors: Dan S. Johnson, Wayne G. Phillips
  • Patent number: 5237627
    Abstract: Disclosed is a system of optical character recognition that first segments a page image into character images. A set of features is extracted and compared to proto-features from a template in order to classify a character, and convert it into a character code. This comparison is performed by comparing each feature of a character image to each proto-feature of each template to create a match rating list which is sorted in descending order. The top match rating and any close ratings are selected and output. To create the ratings, the angles and lengths of the features and proto-features are compared and then the result is normalized to a specific range of values.
    Type: Grant
    Filed: June 27, 1991
    Date of Patent: August 17, 1993
    Assignee: Hewlett-Packard Company
    Inventors: Dan S. Johnson, Mark D. Seaman
  • Patent number: 5212739
    Abstract: Disclosed is a method of optical character recognition that first segments a graphical page image into word images. The method obtains a set of features by extracting smaller outlines of the dark regions in the word images, and then further dissecting each of the smaller outlines into small sections called micro-features. Micro-features are simply sections of character outlines, therefore, they can easily be extracted from the outlines of an entire word without any knowledge about character segmentation boundaries. Micro-features are extracted from an outline by finding the local extremities of the outline and then defining a micro-feature between each pair of sequential extremities. Once extracted, the micro-features are compared to micro-features from an ideal character in order to classify a character, and convert it into a character code.
    Type: Grant
    Filed: April 24, 1992
    Date of Patent: May 18, 1993
    Assignee: Hewlett-Packard Company
    Inventor: Dan S. Johnson
  • Patent number: 4802030
    Abstract: A solution to accurately aligning a read-write head over a previously written data track on both a write protected and not write protected tape is disclosed. A control unit, preferably a programmed microprocessor, electronically provides a sequence of control outputs to move the tape and step the head to locate an edge of the tape. The control unit then moves the head a fixed distance to be over a selected data track. A threshold circuit controls the readout of data from the head of the tape in such a way as to improve edge find reliability.
    Type: Grant
    Filed: June 25, 1986
    Date of Patent: January 31, 1989
    Assignee: Hewlett-Packard Company
    Inventors: Steven G. Henry, Dan S. Johnson, Kurt E. Spears, Mark E. Wanger