×

Endoscopic image enhancement using contrast limited adaptive histogram equalization (CLAHE) implemented in a processor

  • US 10,516,865 B2
  • Filed: 05/16/2016
  • Issued: 12/24/2019
  • Est. Priority Date: 05/17/2015
  • Status: Active Grant
First Claim
Patent Images

1. An endoscope system comprising:

  • an endoscope including a first viewing element and a second viewing element;

    a control unit operatively coupled to the endoscope by a cable, wherein the control unit comprises;

    a base board module;

    one or more processing boards that implement a contrast limited adaptive histogram equalization (CLAHE) algorithm to enhance images obtained by the first viewing element and the second viewing element, wherein the one or more processing boards perform the steps of;

    receiving a first YCbCr color space video stream from the first viewing element and a second YCbCr color space video stream from the second viewing element,converting the first YCbCr color space video stream to a first Lab color space video stream and the second YCbCr color space video stream to a second Lab color space video stream,building and storing first histogram information based on the first Lab color space video stream,building and storing second histogram information based on the second Lab color space video stream,converting the first histogram information into first cumulative distribution function values including applying a first clipping threshold to the first histogram information,converting the second histogram information into second cumulative distribution function values including applying a second clipping threshold to the second histogram information, wherein the second clipping threshold is different from the first clipping threshold,obtaining a first plurality of Lab color space frames from the first Lab color space video stream and a second plurality of Lab color space frames from the second Lab color space video stream,rearranging the first plurality of Lab color space frames to generate a plurality of first delayed Lab streams,rearranging the second plurality of Lab color space frames to generate a plurality of second delayed Lab streams,generating a first enhanced Lab stream based on the plurality of first delayed Lab streams and the first cumulative distribution function values,generating a second enhanced Lab stream based on the plurality of second delayed Lab streams and the second cumulative distribution function values, andsending output video streams indicative of the first enhanced Lab stream and the second enhanced Lab stream to a display.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×