Class Filters


  • public class Filters
    extends java.lang.Object
    Filters
    Version:
    $Revision: 1.2 $
    Author:
    Jim Lawrence, helloNetwork.com, Marc Gimpel, Wimba S.A. (mgimpel@horizonwimba.com)
    • Constructor Summary

      Constructors 
      Constructor Description
      Filters()
      Constructor
    • Method Summary

      All Methods Static Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      static void bw_lpc​(float gamma, float[] lpc_in, float[] lpc_out, int order)
      bw_lpc
      void comb_filter​(float[] exc, int esi, float[] new_exc, int nsi, int nsf, int pitch, float[] pitch_gain, float comb_gain)
      Comb Filter
      static void filter_mem2​(float[] x, int xs, float[] num, float[] den, float[] y, int ys, int N, int ord, float[] mem, int ms)
      filter_mem2
      static void filter_mem2​(float[] x, int xs, float[] num, float[] den, int N, int ord, float[] mem, int ms)
      filter_mem2
      void fir_mem_up​(float[] x, float[] a, float[] y, int N, int M, float[] mem)
      fir_mem_up
      static void fir_mem2​(float[] x, int xs, float[] num, float[] y, int ys, int N, int ord, float[] mem)
      fir_mem2
      static void iir_mem2​(float[] x, int xs, float[] den, float[] y, int ys, int N, int ord, float[] mem)
      iir_mem2
      void init()
      Initialisation
      static void qmf_decomp​(float[] xx, float[] aa, float[] y1, float[] y2, int N, int M, float[] mem)
      Quadrature Mirror Filter to Split the band in two.
      static void residue_percep_zero​(float[] xx, int xxs, float[] ak, float[] awk1, float[] awk2, float[] y, int N, int ord)
      residue_percep_zero
      static void syn_percep_zero​(float[] xx, int xxs, float[] ak, float[] awk1, float[] awk2, float[] y, int N, int ord)
      syn_percep_zero
      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
    • Field Detail

      • last_pitch

        private int last_pitch
      • last_pitch_gain

        private float[] last_pitch_gain
      • smooth_gain

        private float smooth_gain
      • xx

        private float[] xx
    • Constructor Detail

      • Filters

        public Filters()
        Constructor
    • Method Detail

      • init

        public void init()
        Initialisation
      • bw_lpc

        public static final void bw_lpc​(float gamma,
                                        float[] lpc_in,
                                        float[] lpc_out,
                                        int order)
        bw_lpc
        Parameters:
        gamma -
        lpc_in -
        lpc_out -
        order -
      • filter_mem2

        public static final void filter_mem2​(float[] x,
                                             int xs,
                                             float[] num,
                                             float[] den,
                                             int N,
                                             int ord,
                                             float[] mem,
                                             int ms)
        filter_mem2
        Parameters:
        x -
        xs -
        num -
        den -
        N -
        ord -
        mem -
        ms -
      • filter_mem2

        public static final void filter_mem2​(float[] x,
                                             int xs,
                                             float[] num,
                                             float[] den,
                                             float[] y,
                                             int ys,
                                             int N,
                                             int ord,
                                             float[] mem,
                                             int ms)
        filter_mem2
        Parameters:
        x -
        xs -
        num -
        den -
        y -
        ys -
        N -
        ord -
        mem -
        ms -
      • iir_mem2

        public static final void iir_mem2​(float[] x,
                                          int xs,
                                          float[] den,
                                          float[] y,
                                          int ys,
                                          int N,
                                          int ord,
                                          float[] mem)
        iir_mem2
        Parameters:
        x -
        xs -
        den -
        y -
        ys -
        N -
        ord -
        mem -
      • fir_mem2

        public static final void fir_mem2​(float[] x,
                                          int xs,
                                          float[] num,
                                          float[] y,
                                          int ys,
                                          int N,
                                          int ord,
                                          float[] mem)
        fir_mem2
        Parameters:
        x -
        xs -
        num -
        y -
        ys -
        N -
        ord -
        mem -
      • syn_percep_zero

        public static final void syn_percep_zero​(float[] xx,
                                                 int xxs,
                                                 float[] ak,
                                                 float[] awk1,
                                                 float[] awk2,
                                                 float[] y,
                                                 int N,
                                                 int ord)
        syn_percep_zero
        Parameters:
        xx -
        xxs -
        ak -
        awk1 -
        awk2 -
        y -
        N -
        ord -
      • residue_percep_zero

        public static final void residue_percep_zero​(float[] xx,
                                                     int xxs,
                                                     float[] ak,
                                                     float[] awk1,
                                                     float[] awk2,
                                                     float[] y,
                                                     int N,
                                                     int ord)
        residue_percep_zero
        Parameters:
        xx -
        xxs -
        ak -
        awk1 -
        awk2 -
        y -
        N -
        ord -
      • fir_mem_up

        public void fir_mem_up​(float[] x,
                               float[] a,
                               float[] y,
                               int N,
                               int M,
                               float[] mem)
        fir_mem_up
        Parameters:
        x -
        a -
        y -
        N -
        M -
        mem -
      • comb_filter

        public void comb_filter​(float[] exc,
                                int esi,
                                float[] new_exc,
                                int nsi,
                                int nsf,
                                int pitch,
                                float[] pitch_gain,
                                float comb_gain)
        Comb Filter
        Parameters:
        exc - - decoded excitation
        esi -
        new_exc - - enhanced excitation
        nsi -
        nsf - - sub-frame size
        pitch - - pitch period
        pitch_gain - - pitch gain (3-tap)
        comb_gain - - gain of comb filter
      • qmf_decomp

        public static final void qmf_decomp​(float[] xx,
                                            float[] aa,
                                            float[] y1,
                                            float[] y2,
                                            int N,
                                            int M,
                                            float[] mem)
        Quadrature Mirror Filter to Split the band in two. A 16kHz signal is thus divided into two 8kHz signals representing the low and high bands. (used by wideband encoder)
        Parameters:
        xx -
        aa -
        y1 -
        y2 -
        N -
        M -
        mem -