311 research outputs found

    Near-invariant blur for depth and 2D motion via time-varying light field analysis

    Full text link
    Recently, several camera designs have been proposed for either making defocus blur invariant to scene depth or making motion blur invariant to object motion. The benefit of such invariant capture is that no depth or motion estimation is required to remove the resultant spatially uniform blur. So far, the techniques have been studied separately for defocus and motion blur, and object motion has been assumed 1D (e.g., horizontal). This article explores a more general capture method that makes both defocus blur and motion blur nearly invariant to scene depth and in-plane 2D object motion. We formulate the problem as capturing a time-varying light field through a time-varying light field modulator at the lens aperture, and perform 5D (4D light field + 1D time) analysis of all the existing computational cameras for defocus/motion-only deblurring and their hybrids. This leads to a surprising conclusion that focus sweep, previously known as a depth-invariant capture method that moves the plane of focus through a range of scene depth during exposure, is near-optimal both in terms of depth and 2D motion invariance and in terms of high-frequency preservation for certain combinations of depth and motion ranges. Using our prototype camera, we demonstrate joint defocus and motion deblurring for moving scenes with depth variation

    Compressive light field photography using overcomplete dictionaries and optimized projections

    Full text link
    Light field photography has gained a significant research interest in the last two decades; today, commercial light field cameras are widely available. Nevertheless, most existing acquisition approaches either multiplex a low-resolution light field into a single 2D sensor image or require multiple photographs to be taken for acquiring a high-resolution light field. We propose a compressive light field camera architecture that allows for higher-resolution light fields to be recovered than previously possible from a single image. The proposed architecture comprises three key components: light field atoms as a sparse representation of natural light fields, an optical design that allows for capturing optimized 2D light field projections, and robust sparse reconstruction methods to recover a 4D light field from a single coded 2D projection. In addition, we demonstrate a variety of other applications for light field atoms and sparse coding, including 4D light field compression and denoising.Natural Sciences and Engineering Research Council of Canada (NSERC postdoctoral fellowship)United States. Defense Advanced Research Projects Agency (DARPA SCENICC program)Alfred P. Sloan Foundation (Sloan Research Fellowship)United States. Defense Advanced Research Projects Agency (DARPA Young Faculty Award

    The effect of solar flare on agriculture

    No full text
    A demo project for how to make astronomy research in OSF。This project contains raw data and analysis scripts for the paper"Impact of Stellar Superflares on Planetary Habitability", by Yosuke A. Yamashiki, Hiroyuki Maehara, Vladimir Airapetian, Yuta Notsu, Tatsuhiko Sato, Shota Notsu, Ryusuke Kuroki, Keiya Murashima, Hiroaki Sato,Kosuke Namekata, Takanori Sasaki, Thomas B. Scott, Hina Bando, Subaru Nashimoto, Fuka Takagi, Cassandra Ling, Daisaku Nogami, Kazunari Shibata(Astrophysical Journal

    The effect of solar flare on agriculture

    No full text
    A demo project for how to make astronomy research in OSF。This project contains raw data and analysis scripts for the paper"Impact of Stellar Superflares on Planetary Habitability", by Yosuke A. Yamashiki, Hiroyuki Maehara, Vladimir Airapetian, Yuta Notsu, Tatsuhiko Sato, Shota Notsu, Ryusuke Kuroki, Keiya Murashima, Hiroaki Sato,Kosuke Namekata, Takanori Sasaki, Thomas B. Scott, Hina Bando, Subaru Nashimoto, Fuka Takagi, Cassandra Ling, Daisaku Nogami, Kazunari Shibata(Astrophysical Journal
    corecore