image analysis Image analysis or imagery analysis is the extraction of meaningful information from images; mainly from digital images by means of digital image processing techniques. Image analysis tasks can be as simple as reading bar coded tags or as soph ...

, a resel (from ''res''olution ''el''ement) represents the actual

spatial resolution In physics and geosciences, the term spatial resolution refers to distance between independent measurements, or the physical dimension that represents a pixel of the image. While in some instruments, like cameras and telescopes, spatial resolut ...

in an image or a volumetric dataset. The number of resels in the image may be lower or equal to the number of pixel/voxels in the image. In an actual image the resels can vary across the image and indeed the local resolution can be expressed as "resels per

pixel In digital imaging, a pixel (abbreviated px), pel, or picture element is the smallest addressable element in a raster image, or the smallest point in an all points addressable display device. In most digital display devices, pixels are the ...

" (or "resels per

voxel In 3D computer graphics, a voxel represents a value on a regular grid in three-dimensional space. As with pixels in a 2D bitmap, voxels themselves do not typically have their position (i.e. coordinates) explicitly encoded with their values. I ...

"). In functional neuroimaging analysis, an

estimate Estimation (or estimating) is the process of finding an estimate or approximation, which is a value that is usable for some purpose even if input data may be incomplete, uncertain, or unstable. The value is nonetheless usable because it is de ...

of the number of resels together with

random field In physics and mathematics, a random field is a random function over an arbitrary domain (usually a multi-dimensional space such as \mathbb^n). That is, it is a function f(x) that takes on a random value at each point x \in \mathbb^n(or some other ...

theory is used in

statistical inference Statistical inference is the process of using data analysis to infer properties of an underlying distribution of probability.Upton, G., Cook, I. (2008) ''Oxford Dictionary of Statistics'', OUP. . Inferential statistical analysis infers properti ...

. Keith Worsley has proposed an estimate for the number of resels/roughness. The word "resel" is related to the words "

", "

texel Texel (; Texels dialect: ) is a municipality and an island with a population of 13,643 in North Holland, Netherlands. It is the largest and most populated island of the West Frisian Islands in the Wadden Sea. The island is situated north of Den ...

", and "

", and Waldo R. Tobler is probably among the first to use the word.

References

Bibliography

* Keith J. Worsley,
An unbiased estimator for the roughness of a multivariate Gaussian random field
',

Technical report A technical report (also scientific report) is a document that describes the process, progress, or results of technical or scientific research or the state of a technical or scientific research problem. It might also include recommendations and c ...

, 2000 July. * * {{Cite journal , doi = 10.1111/j.1538-4632.1985.tb00846.x , author = Waldo R. Tobler, S. Kennedy , title = Smooth multidimensional interpolation , journal = Geographical Analysis , volume = 17 , issue = 3 , pages = 251–257 , date = July 1985 , doi-access= free Image processing Computer graphics

See also

References

Bibliography