fir_filter_with_buffer.h

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/* -*- c++ -*- */
/*
 * Copyright 2010,2012 Free Software Foundation, Inc.
 *
 * This file is part of GNU Radio
 *
 * GNU Radio is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 3, or (at your option)
 * any later version.
 *
 * GNU Radio is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with GNU Radio; see the file COPYING.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street,
 * Boston, MA 02110-1301, USA.
 */

#ifndef INCLUDED_FILTER_FIR_FILTER_WITH_BUFFER_H
#define INCLUDED_FILTER_FIR_FILTER_WITH_BUFFER_H

#include <filter/api.h>
#include <vector>
#include <gr_complex.h>

namespace gr {
  namespace filter {
    namespace kernel {

      /*!
       * \brief FIR with internal buffer for float input, float output and float taps.
       * \ingroup filter
       */
      class FILTER_API fir_filter_with_buffer_fff
      {
      private:
        std::vector<float> d_taps;
        unsigned int  d_ntaps;
        float        *d_buffer_ptr;
        float        *d_buffer;
        unsigned int  d_idx;
        float       **d_aligned_taps;
        float        *d_output;
        int           d_align;
        int           d_naligned;

      public:
      
        // CONSTRUCTORS

        /*!
         * \brief construct new FIR with given taps.
         *
         * Note that taps must be in forward order, e.g., coefficient 0 is
         * stored in new_taps[0], coefficient 1 is stored in
         * new_taps[1], etc.
         */
        fir_filter_with_buffer_fff(const std::vector<float> &taps);

        ~fir_filter_with_buffer_fff();

        // MANIPULATORS

        /*!
         * \brief compute a single output value.
         *
         * \p input is a single input value of the filter type
         *
         * \returns the filtered input value.
         */
        float filter(float input);

        /*!
         * \brief compute a single output value; designed for decimating filters.
         *
         * \p input is a single input value of the filter type. The value of dec is the
         *    decimating value of the filter, so input[] must have dec valid values.
         *    The filter pushes dec number of items onto the circ. buffer before computing
         *    a single output.
         *
         * \returns the filtered input value.
         */
        float filter(const float input[], unsigned long dec);

        /*!
         * \brief compute an array of N output values.
         *
         * \p input must have (n - 1 + ntaps()) valid entries.
         * input[0] .. input[n - 1 + ntaps() - 1] are referenced to compute the output values.
         */
        void filterN(float output[],
                     const float input[],
                     unsigned long n);

        /*!
         * \brief compute an array of N output values, decimating the input
         *
         * \p input must have (decimate * (n - 1) + ntaps()) valid entries.
         * input[0] .. input[decimate * (n - 1) + ntaps() - 1] are referenced to
         * compute the output values.
         */
        void filterNdec(float output[], const float input[],
                        unsigned long n, unsigned long decimate);

        // ACCESSORS

        /*!
         * \return number of taps in filter.
         */
        unsigned int ntaps() const { return d_ntaps; }

        /*!
         * \brief install \p new_taps as the current taps.
         */
        void set_taps(const std::vector<float> &taps);

        /*!
         * \return current taps
         */
        std::vector<float> taps() const;
      };


      /**************************************************************/


      /*!
       * \brief FIR with internal buffer for gr_complex input, gr_complex output and gr_complex taps.
       * \ingroup filter
       */
      class FILTER_API fir_filter_with_buffer_ccc
      {
      private:
        std::vector<gr_complex> d_taps;
        unsigned int  d_ntaps;
        gr_complex   *d_buffer_ptr;
        gr_complex   *d_buffer;
        unsigned int  d_idx;
        gr_complex  **d_aligned_taps;
        gr_complex   *d_output;
        int           d_align;
        int           d_naligned;

      public:
      
        // CONSTRUCTORS

        /*!
         * \brief construct new FIR with given taps.
         *
         * Note that taps must be in forward order, e.g., coefficient 0 is
         * stored in new_taps[0], coefficient 1 is stored in
         * new_taps[1], etc.
         */
        fir_filter_with_buffer_ccc(const std::vector<gr_complex> &taps);

        ~fir_filter_with_buffer_ccc();

        // MANIPULATORS

        /*!
         * \brief compute a single output value.
         *
         * \p input is a single input value of the filter type
         *
         * \returns the filtered input value.
         */
        gr_complex filter(gr_complex input);

        /*!
         * \brief compute a single output value; designed for decimating filters.
         *
         * \p input is a single input value of the filter type. The value of dec is the
         *    decimating value of the filter, so input[] must have dec valid values.
         *    The filter pushes dec number of items onto the circ. buffer before computing
         *    a single output.
         *
         * \returns the filtered input value.
         */
        gr_complex filter(const gr_complex input[], unsigned long dec);

        /*!
         * \brief compute an array of N output values.
         *
         * \p input must have (n - 1 + ntaps()) valid entries.
         * input[0] .. input[n - 1 + ntaps() - 1] are referenced to compute the output values.
         */
        void filterN(gr_complex output[],
                     const gr_complex input[],
                     unsigned long n);

        /*!
         * \brief compute an array of N output values, decimating the input
         *
         * \p input must have (decimate * (n - 1) + ntaps()) valid entries.
         * input[0] .. input[decimate * (n - 1) + ntaps() - 1] are referenced to
         * compute the output values.
         */
        void filterNdec(gr_complex output[], const gr_complex input[],
                        unsigned long n, unsigned long decimate);

        // ACCESSORS

        /*!
         * \return number of taps in filter.
         */
        unsigned int ntaps() const { return d_ntaps; }

        /*!
         * \brief install \p new_taps as the current taps.
         */
        void set_taps(const std::vector<gr_complex> &taps);

        /*!
         * \return current taps
         */
        std::vector<gr_complex> taps() const;
      };


      /**************************************************************/


      /*!
       * \brief FIR with internal buffer for gr_complex input, gr_complex output and gr_complex taps.
       * \ingroup filter
       */
      class FILTER_API fir_filter_with_buffer_ccf
      {
      private:
        std::vector<float> d_taps;
        unsigned int  d_ntaps;
        gr_complex   *d_buffer_ptr;
        gr_complex   *d_buffer;
        unsigned int  d_idx;
        float       **d_aligned_taps;
        gr_complex   *d_output;
        int           d_align;
        int           d_naligned;

      public:
      
        // CONSTRUCTORS

        /*!
         * \brief construct new FIR with given taps.
         *
         * Note that taps must be in forward order, e.g., coefficient 0 is
         * stored in new_taps[0], coefficient 1 is stored in
         * new_taps[1], etc.
         */
        fir_filter_with_buffer_ccf(const std::vector<float> &taps);

        ~fir_filter_with_buffer_ccf();

        // MANIPULATORS

        /*!
         * \brief compute a single output value.
         *
         * \p input is a single input value of the filter type
         *
         * \returns the filtered input value.
         */
        gr_complex filter(gr_complex input);

        /*!
         * \brief compute a single output value; designed for decimating filters.
         *
         * \p input is a single input value of the filter type. The value of dec is the
         *    decimating value of the filter, so input[] must have dec valid values.
         *    The filter pushes dec number of items onto the circ. buffer before computing
         *    a single output.
         *
         * \returns the filtered input value.
         */
        gr_complex filter(const gr_complex input[], unsigned long dec);

        /*!
         * \brief compute an array of N output values.
         *
         * \p input must have (n - 1 + ntaps()) valid entries.
         * input[0] .. input[n - 1 + ntaps() - 1] are referenced to compute the output values.
         */
        void filterN(gr_complex output[],
                     const gr_complex input[],
                     unsigned long n);

        /*!
         * \brief compute an array of N output values, decimating the input
         *
         * \p input must have (decimate * (n - 1) + ntaps()) valid entries.
         * input[0] .. input[decimate * (n - 1) + ntaps() - 1] are referenced to
         * compute the output values.
         */
        void filterNdec(gr_complex output[], const gr_complex input[],
                        unsigned long n, unsigned long decimate);

        // ACCESSORS

        /*!
         * \return number of taps in filter.
         */
        unsigned int ntaps() const { return d_ntaps; }

        /*!
         * \brief install \p new_taps as the current taps.
         */
        void set_taps(const std::vector<float> &taps);

        /*!
         * \return current taps
         */
        std::vector<float> taps() const;
      };


    } /* namespace kernel */
  } /* namespace filter */
} /* namespace gr */

#endif /* INCLUDED_FILTER_FIR_FILTER_WITH_BUFFER_H */