Libav
dcadsp.c
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1 /*
2  * Copyright (c) 2004 Gildas Bazin
3  * Copyright (c) 2010 Mans Rullgard <mans@mansr.com>
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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  * Libav 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 Libav; 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 "libavutil/intreadwrite.h"
25 #include "dcadsp.h"
26 
27 static void int8x8_fmul_int32_c(float *dst, const int8_t *src, int scale)
28 {
29  float fscale = scale / 16.0;
30  int i;
31  for (i = 0; i < 8; i++)
32  dst[i] = src[i] * fscale;
33 }
34 
35 static inline void
36 dca_lfe_fir(float *out, const float *in, const float *coefs,
37  int decifactor, float scale)
38 {
39  float *out2 = out + decifactor;
40  const float *cf0 = coefs;
41  const float *cf1 = coefs + 256;
42  int j, k;
43 
44  /* One decimated sample generates 2*decifactor interpolated ones */
45  for (k = 0; k < decifactor; k++) {
46  float v0 = 0.0;
47  float v1 = 0.0;
48  for (j = 0; j < 256 / decifactor; j++) {
49  float s = in[-j];
50  v0 += s * *cf0++;
51  v1 += s * *--cf1;
52  }
53  *out++ = v0 * scale;
54  *out2++ = v1 * scale;
55  }
56 }
57 
58 static void dca_qmf_32_subbands(float samples_in[32][8], int sb_act,
59  SynthFilterContext *synth, FFTContext *imdct,
60  float synth_buf_ptr[512],
61  int *synth_buf_offset, float synth_buf2[32],
62  const float window[512], float *samples_out,
63  float raXin[32], float scale)
64 {
65  int i;
66  int subindex;
67 
68  for (i = sb_act; i < 32; i++)
69  raXin[i] = 0.0;
70 
71  /* Reconstructed channel sample index */
72  for (subindex = 0; subindex < 8; subindex++) {
73  /* Load in one sample from each subband and clear inactive subbands */
74  for (i = 0; i < sb_act; i++) {
75  unsigned sign = (i - 1) & 2;
76  uint32_t v = AV_RN32A(&samples_in[i][subindex]) ^ sign << 30;
77  AV_WN32A(&raXin[i], v);
78  }
79 
80  synth->synth_filter_float(imdct, synth_buf_ptr, synth_buf_offset,
81  synth_buf2, window, samples_out, raXin, scale);
82  samples_out += 32;
83  }
84 }
85 
86 static void dca_lfe_fir0_c(float *out, const float *in, const float *coefs,
87  float scale)
88 {
89  dca_lfe_fir(out, in, coefs, 32, scale);
90 }
91 
92 static void dca_lfe_fir1_c(float *out, const float *in, const float *coefs,
93  float scale)
94 {
95  dca_lfe_fir(out, in, coefs, 64, scale);
96 }
97 
99 {
100  s->lfe_fir[0] = dca_lfe_fir0_c;
101  s->lfe_fir[1] = dca_lfe_fir1_c;
106 }