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SIGGRAPH 2007 · Detailed examples

Coded Aperture Photography

Ashok Veeraraghavan, Ramesh Raskar, Amit Agrawal, Ankit Mohan, and Jack Tumblin

Camera with a patterned mask placed in the lens aperture.
Camera with a patterned mask placed in the lens aperture.

Overview

Refocus a single
coded photograph.

An aperture-plane mask shapes defocus blur so that it can be inverted. The design enables deblurring and full-resolution digital refocusing from one coded-aperture image.

01

Defocus
deblurring

The eye-chart example uses a 7 × 7 invertible amplitude mask and 21 pixels of blur. Deblurring restores small text that is washed out in the captured photograph. The blur follows the mask’s shape rather than the circular shape of a conventional out-of-focus aperture.

Eye-chart input and deblurred result using the coded aperture.
Eye-chart input and deblurred result using the coded aperture.

02

Full-resolution digital refocusing

These examples were captured with a Canon Digital Rebel XT and a 100 mm lens. After estimating layered depths, refocusing brings an out-of-focus region into focus. The captured blur follows the 7 × 7 mask pattern.

The face becomes sharp in the refocused image while the painting becomes blurred.
The face becomes sharp in the refocused image while the painting becomes blurred.
Full-resolution refocusing of the book scene.
Full-resolution refocusing of the book scene.
03

Two mask-based
designs

Coded-aperture photography is one of the two designs in the SIGGRAPH 2007 Dappled Photography paper. The other uses a high-frequency mask near the sensor to capture a light field. Light field refocusing has lower spatial resolution but does not require PSF estimation because the angular information is captured.