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 "mlpdsp.h"
24 #include "mlp.h"
25 
27  int firorder, int iirorder,
28  unsigned int filter_shift, int32_t mask, int blocksize,
29  int32_t *sample_buffer)
30 {
31  int32_t *firbuf = state;
32  int32_t *iirbuf = state + MAX_BLOCKSIZE + MAX_FIR_ORDER;
33  const int32_t *fircoeff = coeff;
34  const int32_t *iircoeff = coeff + MAX_FIR_ORDER;
35  int i;
36 
37  for (i = 0; i < blocksize; i++) {
38  int32_t residual = *sample_buffer;
39  unsigned int order;
40  int64_t accum = 0;
41  int32_t result;
42 
43  for (order = 0; order < firorder; order++)
44  accum += (int64_t) firbuf[order] * fircoeff[order];
45  for (order = 0; order < iirorder; order++)
46  accum += (int64_t) iirbuf[order] * iircoeff[order];
47 
48  accum = accum >> filter_shift;
49  result = (accum + residual) & mask;
50 
51  *--firbuf = result;
52  *--iirbuf = result - accum;
53 
54  *sample_buffer = result;
55  sample_buffer += MAX_CHANNELS;
56  }
57 }
58 
60 {
62  if (ARCH_X86)
64 }
#define MAX_FIR_ORDER
The maximum number of taps in IIR and FIR filters.
Definition: mlp.h:64
static const uint16_t mask[17]
Definition: lzw.c:37
#define ARCH_X86
Definition: config.h:35
static void ff_mlp_filter_channel(int32_t *state, const int32_t *coeff, int firorder, int iirorder, unsigned int filter_shift, int32_t mask, int blocksize, int32_t *sample_buffer)
Definition: mlpdsp.c:26
#define MAX_BLOCKSIZE
void(* mlp_filter_channel)(int32_t *state, const int32_t *coeff, int firorder, int iirorder, unsigned int filter_shift, int32_t mask, int blocksize, int32_t *sample_buffer)
Definition: mlpdsp.h:28
int32_t
synthesis window for stochastic i
void ff_mlpdsp_init_x86(MLPDSPContext *c)
Definition: x86/mlpdsp.c:177
#define MAX_CHANNELS
Definition: aac.h:42
static const double coeff[2][5]
Definition: vf_ow.c:64
static uint32_t state
Definition: trasher.c:27
static double c[64]
void ff_mlpdsp_init(MLPDSPContext *c)
Definition: mlpdsp.c:59