|Image Processing Toolbox User's Guide|
The operation called correlation is closely related to convolution. In correlation, the value of an output pixel is also computed as a weighted sum of neighboring pixels. The difference is that the matrix of weights, in this case called the correlation kernel, is not rotated during the computation. The filter design functions in the Image Processing Toolbox return correlation kernels.
The following figure shows how to compute the (2,4) output pixel of the correlation of
h is a correlation kernel instead of a convolution kernel, using these steps:
The (2,4) output pixel from the correlation is
Computing the (2,4) Output of Correlation
|Convolution||Filtering Using imfilter|
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