Assertion: defocus blur | /r/HasProperty | convolution
Facets:
value: by a uniform disk
type: OTHER
value: to a first approximation
type: OTHER
Source sentences:
text: To a first approximation, defocus blur is convolution by a uniform disk, a more computationally intensive operation than the "standard" Gaussian blur; the former produces sharp circles around highlights whereas the latter is a much softer effect.