denoise                 package:rwt                 R Documentation

_W_a_v_e_l_e_t-_b_a_s_e_d _D_e_n_o_i_s_i_n_g

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

     Denoise the signal 'x' using the 2-band wavelet system described
     by the filter 'h' using either the traditional discrete wavelet
     transform (DWT) or the linear shift invariant discrete wavelet
     transform (also known as the undecimated DWT (UDWT)).

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

     denoise(x, h, type, option)
     denoise.dwt(x, h, option = default.dwt.option)
     denoise.udwt(x, h, option = default.udwt.option)

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

       x: 1D or 2D signal to be denoised

       h: Scaling filter to be applied

    type: Type of transform. Valid values are:

            'DWT.TRANSFORM.TYPE'
            'UDWT.TRANSFORM.TYPE'

  option: List containing desired transformation settings

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

     The transformation settings in the 'option' list are:

     _t_h_r_e_s_h_o_l_d._l_o_w._p_a_s_s._p_a_r_t: Logical flag. If 'TRUE', threshold the
          low-pass component.

     _t_h_r_e_s_h_o_l_d._m_u_l_t_i_p_l_i_e_r: 'thld = c*MAD(noise_estimate)' 

     _v_a_r_i_a_n_c_e._e_s_t_i_m_a_t_o_r: Valid values are:

            MAD.VARIANCE.ESTIMATOR  Mean absolute deviation
            STD.VARIANCE.ESTIMATOR  Classical numerical std estimate


     _t_h_r_e_s_h_o_l_d._t_y_p_e: Valid values are:

            SOFT.THRESHOLD.TYPE  Soft thresholding
            HARD.THRESHOLD.TYPE  Hard thresholding


     _n_u_m._d_e_c_o_m_p_r_e_s_s_i_o_n._l_e_v_e_l_s: Number of levels in wavelet
          decomposition. Setting this to 'MAX.DECOMPOSITION' will allow
          maximal decomposition.

     _t_h_r_e_s_h_o_l_d: Actual threshold to use. Setting this to anything but
          'CALC.THRESHOLD.TO.USE' will disable the 'variance.estimator'
          setting.

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

     Returns a list with components: 

      xd: Estimate of noise free signal

      xn: Estimated noise signal ('x'-'xd')

  option: List of actual parameters used. It is configured the same way
          as the input option list with an additional element -
          'option[[7]] = type'. 

_N_o_t_e:

     Both 'denoise.dwt' and 'denoise.udwt' are convenience routines
     that call the 'denoise' routine with appropriate default
     arguments.

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

     P. Roebuck, roebuck@mdanderson.org

_R_e_f_e_r_e_n_c_e_s:

     ~put references to the literature/web site here ~

_E_x_a_m_p_l_e_s:

     sig <- makesig(SIGNAL.DOPPLER)
     h <- daubcqf(6)
     ret.dwt <- denoise.dwt(sig$x, h$h.0)

