filter2               package:EBImage               R Documentation

_2_D _C_o_n_v_o_l_u_t_i_o_n _F_i_l_t_e_r

_D_e_s_c_r_i_p_t_i_o_n:

     2D convolution-based linear filter for images and matrix data.

_U_s_a_g_e:

       ## S4 methods for signatures 'x=Image' or 'x=array' and
       ## 'filter=matrix' or 'filter=missing'
       filter2(x, filter, ...)
       
       ## S4 method for signature 'Image':
       sharpen2(x, ...)
       
       mkball(n=15, pow=1)
       mkbox(n=15)

_A_r_g_u_m_e_n_t_s:

       x: An object of 'Image' in Grayscale mode, a numeric  'array' or
          a 'matrix'. 

  filter: A square matrix with odd dimensions. 

       n: The size of the filter matrix (odd number). 

     pow: The power of the function used to fill in the matrix. 

     ...: Reserved. 

_D_e_t_a_i_l_s:

     The convolution filter is based on 'fft' transforms.

     If 'x' is an 'array', the filter is applied per frame (as to
     images).

     'sharpen2' uses 'filter2' to sharpen grayscale images by
     subtracting a slightly blurred image with the center pixel
     excluded.

_V_a_l_u_e:

     'filter2' and '' return a transformed object of the same class as 
     'x'.

     'mkball' and 'mkbox' return a square matrix that can be used for 
     'filter2'.

_A_u_t_h_o_r(_s):

     'filter2' author: Gregoire Pau, gpau@ebi.ac.uk, 2007

     'sharpen2' author: Oleg Sklyar, osklyar@ebi.ac.uk, 2007

_S_e_e _A_l_s_o:

     ' Image, fft '

