Darrell E Jefferson

US Patent:

54265142, Jun 20, 1995

Filed:

Mar 4, 1994

Appl. No.:

8/207246

Inventors:

Darrell E. Jefferson - San Jose CA

Assignee:

Xerox Corporation - Stamford CT

International Classification:

H04N 140

US Classification:

358455

Abstract:

A system and method for creating data values suitable for producing a gray scaled approximation of a facsimile image on a lower resolution display. Facsimile image data is compressed based upon horizontal and vertical scaling factors that depend upon the number and organization of display screen pixels to be used to produce the gray scaled image verses the number and organization of pixels in the facsimile image. A conversion vector having entries in a one-to-one relationship with the display pixels of a display scan line is formed. Numerical values are then added to or subtracted from the conversion vector entries associated with the beginning and ending of the black runs of the facsimile image, as determined by using the horizontal scaling factor. The numerical values themselves depend upon how much of the conversion vector entry is spanned by the scaled black facsimile image run length. The contents of the conversion vector are then used to determine final intensity values suitable for controlling the intensity of individual pixels of a display scan line.

US Patent:

52990184, Mar 29, 1994

Filed:

Mar 20, 1992

Appl. No.:

7/856000

Inventors:

Darrell E. Jefferson - San Jose CA

Assignee:

Xerox Corporation - Stamford CT

International Classification:

H04N 712

US Classification:

3582611

Abstract:

A system and method of converting facsimile image data as received by any one of a plurality of fax cards into data stored in a file structure that assists use of the facsimile image by application software and which permits efficient processing of the image by a host computer. The data structure is composed of a file header containing information relating to the dimensions of the facsimile image as converted and stored, and pages of facsimile image data which include page headers that specify the number of pixels in each scan line. The pages further include byte-boundary-limited binary encoded run lengths and end-of-line characters at the ends of each scan line that are used to store the facsimile images. The data in representing the last run length of each scan line is not stored, but is determinable using other information in the pages. Multiple facsimile images can be stored in a single data file by storing separate images in different pages.

US Patent:

56822502, Oct 28, 1997

Filed:

Dec 20, 1994

Appl. No.:

8/359788

Inventors:

Darrell E. Jefferson - San Jose CA

Assignee:

Xerox Corporation - Stamford CT

International Classification:

H04N 712

US Classification:

358448

Abstract:

A computer implemented method of preventing the reproduction of specks while reproducing an image including specks represented via source scan lines. According to the method, on a scan like-by-scan line basis, each source scan line signal is transformed into speckless output run lengths. A source run length is selected and examined by a processor to determine whether it represents part of a speck. If the selected source run length might represent a speck, the processor determines whether the selected source run length can be protected from removal. If it cannot, the length of the selected run length and its subsequent neighbor are added to the output run length. As a result, the speck represented by the selected run length disappears from the image by merger with adjacent source run lengths. On the other hand, if the selected source run length is protected from removal, an output run length is output that represents source run length(s) previous to the selected source run length. A new output run length is then defined whose length and color are the same as the selected source run length.

US Patent:

52415899, Aug 31, 1993

Filed:

Mar 20, 1992

Appl. No.:

7/856005

Inventors:

Darrell E. Jefferson - San Jose CA

Assignee:

Xerox Corporation - Stamford CT

International Classification:

H04M 127

US Classification:

379355

Abstract:

A system and method for automatically examining and correcting telephone numbers to increase the likelihood of establishing communication between a local device, such as a fax card or modem, and a remote device. Proposed telephone numbers are identified and compared against user specified comparison templates to determine if the proposed numbers are proper for establishing communication. If they are, they are approved for dialing. However, if they are not, the proposed numbers are modified according to user specified rules which form output templates. The modified number is then approved for dialing. The system is beneficially implemented using a computer which stores a set of comparison templates and a set of associated output templates in memory. The computer compares a specified number, corrects it as required, and applies it to the local device for dialing.

US Patent:

57455961, Apr 28, 1998

Filed:

May 1, 1995

Appl. No.:

8/432215

Inventors:

Darrell E. Jefferson - San Jose CA

Assignee:

Xerox Corporation - Stanford CT

International Classification:

G06K 934
G06K 948

US Classification:

382176

Abstract:

A computer-implemented method of highlighting text regions within a first scan line signal including image regions. Text/image segmentation begins by identifying a set of edges of a possible text region within the scan line signal. Next, without reference to a second scan line signal, it is determined whether the set of edges of the possible text region first form a text region. If the set of edges form a text region, then the average pel intensity value of the text region is calculated. Afterward, the intensity values of those pels within the text region whose values differ from the average are modified.

US Patent:

20190349786, Nov 14, 2019

Filed:

May 8, 2018

Appl. No.:

15/974520

Inventors:

- Alpharetta GA, US
Lawrence Harris - Duluth GA, US
Darrell Jefferson - Roswell GA, US
James Patrick Hanley - Decatur GA, US

International Classification:

H04W 24/02
H04W 48/16
H04W 76/10
H04W 40/02
H04W 36/16

Abstract:

Systems and methods for managing nodes in mesh networks are provided. A parent node may switch PANs and coordinate the switch with its child nodes. The parent node and its child nodes may maintain timing synchronization information for a current PAN and a new PAN. The parent node and its child nodes may switch to the new PAN using the same switching time.

US Patent:

20150110108, Apr 23, 2015

Filed:

Oct 22, 2013

Appl. No.:

14/059846

Inventors:

- Alpharetta GA, US
Darrell Jefferson - Roswell GA, US

Assignee:

Landis+Gyr Innovations, Inc. - Alpharetta GA

International Classification:

H04L 12/24
H04L 12/911
H04L 29/06

US Classification:

370392

Abstract:

Systems and methods are disclosed for distributed data transmission in an RF mesh network or other data network. An exemplary system includes at least two distribution devices. A first distribution device can receive a first data message that includes a first header and payload data. The first distribution device can determine that the second distribution device is not identified in the first header as receiving the payload data. The first distribution device can generate a second data message based on determining that the second distribution device is not identified in the first header. The second data message includes the payload data and the second header. The second header identifies the second distribution device as being selected to receive the payload data. The first distribution device transmits the second data message to the second distribution device.