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normxcorr2

Normalized two-dimensional cross-correlation

Syntax

Description

C = normxcorr2(TEMPLATE,A) computes the normalized cross-correlation of the matrices TEMPLATE and A. The matrix A must be larger than the matrix TEMPLATE for the normalization to be meaningful. The values of TEMPLATE cannot all be the same. The resulting matrix C contains the correlation coefficients, which can range in value from -1.0 to 1.0.

Class Support

The input matrices can be of class uint8, uint16, or double.

Algorithm

normxcorr2 uses the following general procedure:

  1. Calculate cross-correlation in the spatial or the frequency domain, depending on size of images.
  2. Calculate local sums by precomputing running sums. [1]
  3. Use local sums to normalize the cross-correlation to get correlation coefficients. [2]

Example

See Also

corrcoef

References

[1]  Lewis, J. P., "Fast Normalized Cross-Correlation," Industrial Light & Magic, <http://www.idiom.com/~zilla/Papers/nvisionInterface/nip.html>

[2]  Haralick, Robert M., and Linda G. Shapiro, Computer and Robot Vision, Volume II, Addison-Wesley, 1992, pp. 316-317.


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