![]() ![]() We provide 24 carefully designed synthetic, densely sampled 4D light fields with highly accurate disparity ground truth. To overcome these difficulties, we propose a novel light field benchmark. The performance of newly proposed methods is often demonstrated qualitatively on a handful of images, making quantitative comparison and targeted progress very difficult. ![]() In the emergent light field community, a comparable benchmark and evaluation methodology is still missing. In computer vision communities such as stereo, optical flow, or visual tracking, commonly accepted and widely used benchmarks have enabled objective comparison and boosted scientific progress. We demonstrate this using an array of 30 videoresolution cameras initial homographies and shifts are performed on per-camera FPGAs, and additions and a final warp are performed on 3 PCs. Being able to vary the focus by simply shifting and adding images is relatively simple to implement in hardware and facilitates a real-time implementation. This shear-warp factorization permits these tilted focal planes to be synthesized as efficiently as frontoparallel planes. We also show that there are camera configurations and families of tilted focal planes for which the warps can be factorized into an initial homography followed by shifts. We characterize the warps using a new rank- 1 constraint that lets us focus on any plane, without having to perform a metric calibration of the cameras. In this paper, we analyze the warps required for tilted focal planes and arbitrary camera configurations. If the cameras lie on a plane, it has been previously shown that after an initial homography, one can move the focus through a family of planes that are parallel to the camera plane by merely shifting and adding the images. This provides the ability to see through partial occluders such as foliage and crowds, making it a potentially powerful tool for surveillance. Synthetic aperture focusing consists of warping and adding together the images in a 4D light field so that objects lying on a specified surface are aligned and thus in focus, while objects lying of this surface are misaligned and hence blurred. We have used our prototype to take hundreds of light field photographs, and we present examples of portraits, high-speed action and macro close-ups. To the photographer, the plenoptic camera operates exactly like an ordinary hand-held camera. These capabilities argue for a different strategy in designing photo- graphic imaging systems. Especially in the macrophotography regime, we demonstrate that we can also com- pute synthetic photographs from a range of different viewpoints. This property allows us to extend the depth of field of the camera without reducing the aperture, en- abling shorter exposures and lower image noise. We show that a linear increase in the resolution of images under each microlens results in a linear increase in the sharpness of the refocused photographs. By re-sorting the measured rays of light to where they would have terminated in slightly different, synthetic cameras, we can compute sharp photographs focused at different depths. Each microlens measures not just the total amount of light deposited at that location, but how much light ar- rives along each ray. This is achieved by in- serting a microlens array between the sensor and main lens, creat- ing a plenoptic camera. This paper presents a camera that samples the 4D light field on its sensor in a single photographic exposure. In addition to refocusing, light fields also enable the user to interact with the viewpoint, which can be easily included in the proposed generalized shift-and-sum framework.įor more results, including videos, go to Further, we show that the inclusion of depth information allows for intuitive interactive methods for placement of the refocus plane. For this purpose we introduce a generalized shift-and-sum framework. ![]() In this paper, we address the interactivity of a lesser-known light field operation: refocus to a non-frontoparallel plane, simulating the result of traditional tilt-shift photography. A common interactive method for such an operation utilizes disparity estimations, readily available from the light field, to allow the user to point-and-click on the image to chose the location of the refocus plane. One of the earliest and most common light field operations is digital refocus, enabling the user to choose the focus and depth-of-field for the image after capture. Since their introduction more than two decades ago, light fields have gained considerable interest in graphics and vision communities due to their ability to provide the user with interactive visual content.
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