imwr.imwdc            package:wavethresh            R Documentation

_I_n_v_e_r_s_e _t_w_o-_d_i_m_e_n_s_i_o_n_a_l _d_i_s_c_r_e_t_e _w_a_v_e_l_e_t _t_r_a_n_s_f_o_r_m.

_D_e_s_c_r_i_p_t_i_o_n:

     Inverse two-dimensional discrete wavelet transform.

_U_s_a_g_e:

     imwr.imwdc(imwd, verbose=FALSE, ...

_A_r_g_u_m_e_n_t_s:

    imwd: An object of class 'imwdc'. This type of object is returned
          by 'threshold.imwd' and is a 'compress.imwd' compressed
          version of an 'imwd' object.

 verbose: If this argument is true then informative messages are
          printed detailing the computations to be performed

     ...: other arguments to supply to the 'imwr' function which is
          called after uncompressing the imwdc object.

_D_e_t_a_i_l_s:

     This function merely uncompresses the supplied 'imwdc.object' and
     passes the resultant 'imwd' object to the 'imwr.imwd' function.

     This function is a method for the generic function 'imwr' for
     class 'imwdc.object'. It can be invoked by calling 'imwr' for an
     object of the appropriate class, or directly by calling imwr.imwdc
     regardless of the class of the object.

_V_a_l_u_e:

     A matrix, of dimension determined by the original data set
     supplied to the initial decomposition (more precisely, determined
     by the 'nlevels' component of the 'imwdc.object'). This matrix is
     the highest resolution level of the reconstruction.

_R_E_L_E_A_S_E:

     Version 3.5.3 Copyright Guy Nason 1994

_S_e_e _A_l_s_o:

     'compress.imwd', 'imwd', 'imwd.object', 'imwr'.

_E_x_a_m_p_l_e_s:

     #
     # Do a decomposition, thresholding, then exact reconstruction
     # Look at the error
     #
     # Test image is just some sort of  square matrix whose side length
     # is a power of two.
     #
     #max( abs(imwr(threshold(imwd(test.image))) - test.image))
     # [1] 62.34
     #
     # The answer is not zero (see contrasting example in the help page for
     # imwr.imwd because we have thresholded the
     # 2D wavelet transform here.

