1. Generalized Autofocus Daniel Vaquero 1,2, Natasha Gelfand 1, Marius Tico 1, Kari Pulli 1, Matthew Turk 2 1 Nokia Research Center, Palo Alto 2 University of California, Santa Barbara

2. All-in-Focus Imaging Images focused at different distances (focal stack) Daniel Vaquero

3. What is our work about? The capture process for focal stacks –For fusion, we use existing techniques, but we do it on-camera Our scenario, typical in camera phones and low-end consumer cameras –Fixed lens aperture –Handheld camera –Limited memory and processing power Daniel Vaquero

4. Contrast-based Passive Autofocus Sharp! Daniel Vaquero

5. Our Method: Generalized Autofocus Contribution: autofocus for focal stacks Find the minimal set of required images to generate an all-in-focus composite –The choice of this set depends on the scene Why is minimizing the number of images important? –Faster capture –Less sensitive to motion –Requires less memory and processing power depth Daniel Vaquero

6. Approach 1) Lens sweep from near focus to far focus –capture metering stack of low-resolution images 2) Analyze sharpness 3) Plane-sweep algorithm to determine the minimal set of required images, runs in linear time 4) Recapture minimal set in high resolution 5) Perform all-in-focus fusion Implementation –Nokia N900 smartphone + Frankencamera + enblend Daniel Vaquero

8. Thank you! Daniel Vaquero www.cs.ucsb.edu/~daniel ilab.cs.ucsb.edu More details: 8:30-10:00 p.m. Poster Session II-2 (Keauhou 1)