HOME  |  NEWS  |  BLOGS  |  MESSAGES  |  FEATURES  |  VIDEOS  |  WEBINARS  |  INDUSTRIES  |  FOCUS ON FUNDAMENTALS
  |  REGISTER  |  LOGIN  |  HELP
Comment
jbswindle
User Rank
Silver
Re: March 20 - Day THREE: Improving Image Understanding by Improving Image Quality
jbswindle   3/20/2013 2:35:36 PM
NO RATINGS
What about correction for optical, mechanical, and pixel vignetting effects?  In analog days this kind of shading error was corrected with scaled parabola signals added to the baseband video at horizontal and vertical rates.  Gradient shading errors were corrected with scaled saw tooth signals added to the baseband video at horizontal and vertical rates.  Feature extraction such as that required for OCR might benefit from shading correction.  OCR binarization algorythms attempt to deal with adjacent pixel levels changed due desired feature brightness dealing with both noise and background brightness changes (perhaps due to background artwork).  I haven't seen anything about shading correction outside of telecine/live studio video camera enviornments.

What, if anything, is done either in the camera itself or in digital post processing to correct shading errors or, indeed, is shading correction even desirable in computer vision processing?

Thank you for a very informative presentation.



Partner Zone
Latest Analysis
A researcher from The Ohio State University has designed objects that harness vibrations from the movement of swaying buildings or bridges to provide alternative energy.
Oak Ridge National Laboratory has developed a carbon fiber production method it wants to share with you: a faster, cheaper, greener method for manufacturing industrial-grade structural carbon fiber.
This slideshow includes several versions of multi-materials machines, two different composites processes including one at microscale, and two vastly different metals processes. Potential game-changers down the line include three microscale processes.
Members of the IEEE Computer Society name cybersecurity as the top technology affecting their industries.
Hosted CAD or PDM systems is an emerging technology that offers many advantages over traditional on premise workstation CAD configurations and is making many companies rethink how to deliver future CAD software solutions.
More:Blogs|News
Quick Poll
The Continuing Education Center offers engineers an entirely new way to get the education they need to formulate next-generation solutions.
Jan 11 - 15, Designing ARM Devices Using Segger Tools
SEMESTERS: 1  |  2  |  3  |  4  |  5  |  6 |  7 | 8 | 9


Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.
Learn More   |   Login   |   Archived Classes
Twitter Feed
Design News Twitter Feed
Like Us on Facebook

Technology Marketplace

Copyright © 2016 UBM Canon, A UBM company, All rights reserved. Privacy Policy | Terms of Service