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Defocus Blur

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Computer Vision

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Synonyms

Out of focus blur

Related Concepts

Definition

Defocus blur is a loss of sharpness that occurs due to integrating light over the area of an aperture when the source of the area being captured is not on the image focal plane, i.e., the area is “out of focus.” The amount of blur that is visible in an image is a function of the lens aperture, the object and focal depth, and the camera pixel (or grain) size.

Background

Image blur can be described by a point spread function (PSF). A PSF models how an imaging system captures a single point in the world – it literally describes how a point “spreads” across an image. An entire image is then made up of a sum of the individual images of every scene point, where each point’s image is affected by the PSF associated with that point. For an image to be “in focus” means that one ideally does not want any image blur at a particular depth of the scene. Thus the PSF should be...

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Author information

Authors and Affiliations

  1. Microsoft Research, Redmond, WA, USA

    Neel Joshi

Authors
  1. Neel Joshi
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Corresponding author

Correspondence to Neel Joshi .

Section Editor information

  1. Osaka University, Suita, Japan

    Yasuyuki Matsushita

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Joshi, N. (2020). Defocus Blur. In: Computer Vision. Springer, Cham. https://doi.org/10.1007/978-3-030-03243-2_511-1

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  • DOI: https://doi.org/10.1007/978-3-030-03243-2_511-1

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  • Publisher Name: Springer, Cham

  • Print ISBN: 978-3-030-03243-2

  • Online ISBN: 978-3-030-03243-2

  • eBook Packages: Springer Reference Computer SciencesReference Module Computer Science and Engineering

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