Lens Correction Technologies Home

ROADIS - Removal of Optical Aberrations in Digital Imaging Systems


This is the homepage for the ROADIS project, which addresses key problems in new and emerging lens correction technologies.

ROADIS is an Enterprise Ireland funded research project being undertaken at CIPA, the Centre for Image Processing and Analysis, Dublin City University, Ireland. The goal of the project is to develop a comprehensive suite of image processing algorithms and software applications, to address a number aberration correction tasks, relating to the production of very high quality digital images.

Background to the ROADIS Project


Dublin City University researchers have developed mathematically-based compensation algorithms to calibrate and remove the main optical aberrations in digital images. A number of innovations have already been patented and the research team continues to develop, refine and test new algorithms, through an on-going research programme.

Most digital optical imaging systems introduce a number of artifacts into an image. The main and best known problems include - lens distortions (often referred to as “barrel” or “pincushion” effects); lateral chromatic aberration (LCA), which shows up as a “colour fringing”; axial chromatic aberration (ACA), which produces a colour dependant blurring; image defocus, which is manifested as depth dependent blur; and vignetting, which results in a fall off in brightness around the periphery of a digital image.



Vendors of digital imaging equipment have two basic options when correcting optical problems - fix the error on the actual device itself; or post-edit the images on a computer using one of the many commercial digital photo-editing packages available.

Example uncorrected and corrected image pair showing removal of colour fringing artifacts.
The key challenge of an embedded or on-device solution is cost. The most direct approach - that of improving the actual camera lens - is very costly, as it often requires sophisticated engineering of the lens assembly. This is really only viable for high end equipment such as professional camera lenses. The research undertaken at DCU offers the option of correcting the images through novel software algorithms, implemented on the device processor, without any improvements to the actual lens. This has applications in many digital imaging devices, including digital cameras, webcams, mobile phones, digital projectors, telescopes and other specialised industrial and medical imaging devices. A software solution represents a very inexpensive and effective approach. Our software architecture has the additional flexibility of also becoming part of a desktop solution if required.

The aberration removal technologies developed by the research are described in more detail in the technology section of the website, which links to the descriptions of the aberrations types, their causes, and the solutions developed in the project.


               

Centre for Image Processing and Analysis, School of Electronic Engineering, Dublin City University, Dublin 9, Ireland