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67 lines
1.8 KiB
C++
67 lines
1.8 KiB
C++
1 year ago
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/*
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* Project 25 IMBE Encoder/Decoder Fixed-Point implementation
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* Developed by Pavel Yazev E-mail: pyazev@gmail.com
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* Version 1.0 (c) Copyright 2009
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*
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* This is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 3, or (at your option)
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* any later version.
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*
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* The software is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
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* See the GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this; see the file COPYING. If not, write to the Free
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* Software Foundation, Inc., 51 Franklin Street, Boston, MA
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* 02110-1301, USA.
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*/
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#include "typedef.h"
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#include "globals.h"
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#include "imbe.h"
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#include "aux_sub.h"
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#include "basic_op.h"
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#include "math_sub.h"
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#include "dc_rmv.h"
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#define CNST_0_99_Q1_15 0x7EB8
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//-----------------------------------------------------------------------------
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// PURPOSE:
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// High-pass filter to remove DC
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//
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//
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// INPUT:
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// *sigin - pointer to input signal buffer
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// *sigout - pointer to output signal buffer
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// *mem - pointer to filter's memory element
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// len - number of input signal samples
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//
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// OUTPUT:
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// None
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//
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// RETURN:
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// Saved filter state in mem
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//
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//-----------------------------------------------------------------------------
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void dc_rmv(Word16 *sigin, Word16 *sigout, Word32 *mem, Word16 len)
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{
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Word32 L_tmp, L_mem;
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L_mem = *mem;
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while(len--)
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{
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L_tmp = L_deposit_h(*sigin++);
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L_mem = L_add(L_mem, L_tmp);
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*sigout++ = round(L_mem);
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L_mem = L_mpy_ls(L_mem, CNST_0_99_Q1_15);
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L_mem = L_sub(L_mem, L_tmp);
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}
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*mem = L_mem;
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}
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