Changes between Version 12 and Version 13 of libpipi/research/filters


Ignore:
Timestamp:
Oct 22, 2008, 3:23:35 PM (11 years ago)
Author:
Sam Hocevar
Comment:

LaTeX shit

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  • libpipi/research/filters

    v12 v13  
    55The usual way to create a Gaussian kernel is to evaluate a Gaussian function at the center of each cell:
    66
    7  k[i][j] = exp(-(i²+j²)/2σ)
     7{{{
     8#!latex
     9$k_{i,j} = e^{-\dfrac{i^2+j^2}{2\sigma}}$
     10}}}
    811
    912This usually works well, except when the kernel is thin (σ < 1). It gets worse when using our generalised kernel:
    1013
    11  k[i][j] = exp(-((i×cosθ-j×sinθ-dx)²+(j×cosθ+i×sinθ-dy)²)/2σ)
     14{{{
     15#!latex
     16$k_{i,j} = e^{-\dfrac{(i\cos\theta-j\sin\theta-dx)^2+(j\cos\theta+i\sin\theta-dy)^2}{2\sigma}}$
     17}}}
    1218
    1319{{{