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mlpdsp.c
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1 /*
2  * Copyright (c) 2007-2008 Ian Caulfield
3  * 2009 Ramiro Polla
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "config.h"
23 #include "libavutil/attributes.h"
24 #include "mlpdsp.h"
25 #include "mlp.h"
26 
28  int firorder, int iirorder,
29  unsigned int filter_shift, int32_t mask,
30  int blocksize, int32_t *sample_buffer)
31 {
32  int32_t *firbuf = state;
33  int32_t *iirbuf = state + MAX_BLOCKSIZE + MAX_FIR_ORDER;
34  const int32_t *fircoeff = coeff;
35  const int32_t *iircoeff = coeff + MAX_FIR_ORDER;
36  int i;
37 
38  for (i = 0; i < blocksize; i++) {
39  int32_t residual = *sample_buffer;
40  unsigned int order;
41  int64_t accum = 0;
42  int32_t result;
43 
44  for (order = 0; order < firorder; order++)
45  accum += (int64_t) firbuf[order] * fircoeff[order];
46  for (order = 0; order < iirorder; order++)
47  accum += (int64_t) iirbuf[order] * iircoeff[order];
48 
49  accum = accum >> filter_shift;
50  result = (accum + residual) & mask;
51 
52  *--firbuf = result;
53  *--iirbuf = result - accum;
54 
55  *sample_buffer = result;
56  sample_buffer += MAX_CHANNELS;
57  }
58 }
59 
61 {
63  if (ARCH_X86)
65 }