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sbrdsp.c
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1 /*
2  * AAC Spectral Band Replication decoding functions
3  * Copyright (c) 2008-2009 Robert Swain ( rob opendot cl )
4  * Copyright (c) 2009-2010 Alex Converse <alex.converse@gmail.com>
5  *
6  * This file is part of Libav.
7  *
8  * Libav is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * Libav is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with Libav; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 #include "config.h"
24 #include "libavutil/attributes.h"
25 #include "sbrdsp.h"
26 
27 static void sbr_sum64x5_c(float *z)
28 {
29  int k;
30  for (k = 0; k < 64; k++) {
31  float f = z[k] + z[k + 64] + z[k + 128] + z[k + 192] + z[k + 256];
32  z[k] = f;
33  }
34 }
35 
36 static float sbr_sum_square_c(float (*x)[2], int n)
37 {
38  float sum0 = 0.0f, sum1 = 0.0f;
39  int i;
40 
41  for (i = 0; i < n; i += 2)
42  {
43  sum0 += x[i + 0][0] * x[i + 0][0];
44  sum1 += x[i + 0][1] * x[i + 0][1];
45  sum0 += x[i + 1][0] * x[i + 1][0];
46  sum1 += x[i + 1][1] * x[i + 1][1];
47  }
48 
49  return sum0 + sum1;
50 }
51 
52 static void sbr_neg_odd_64_c(float *x)
53 {
54  int i;
55  for (i = 1; i < 64; i += 2)
56  x[i] = -x[i];
57 }
58 
59 static void sbr_qmf_pre_shuffle_c(float *z)
60 {
61  int k;
62  z[64] = z[0];
63  z[65] = z[1];
64  for (k = 1; k < 32; k++) {
65  z[64+2*k ] = -z[64 - k];
66  z[64+2*k+1] = z[ k + 1];
67  }
68 }
69 
70 static void sbr_qmf_post_shuffle_c(float W[32][2], const float *z)
71 {
72  int k;
73  for (k = 0; k < 32; k++) {
74  W[k][0] = -z[63-k];
75  W[k][1] = z[k];
76  }
77 }
78 
79 static void sbr_qmf_deint_neg_c(float *v, const float *src)
80 {
81  int i;
82  for (i = 0; i < 32; i++) {
83  v[ i] = src[63 - 2*i ];
84  v[63 - i] = -src[63 - 2*i - 1];
85  }
86 }
87 
88 static void sbr_qmf_deint_bfly_c(float *v, const float *src0, const float *src1)
89 {
90  int i;
91  for (i = 0; i < 64; i++) {
92  v[ i] = src0[i] - src1[63 - i];
93  v[127 - i] = src0[i] + src1[63 - i];
94  }
95 }
96 
97 static av_always_inline void autocorrelate(const float x[40][2],
98  float phi[3][2][2], int lag)
99 {
100  int i;
101  float real_sum = 0.0f;
102  float imag_sum = 0.0f;
103  if (lag) {
104  for (i = 1; i < 38; i++) {
105  real_sum += x[i][0] * x[i+lag][0] + x[i][1] * x[i+lag][1];
106  imag_sum += x[i][0] * x[i+lag][1] - x[i][1] * x[i+lag][0];
107  }
108  phi[2-lag][1][0] = real_sum + x[ 0][0] * x[lag][0] + x[ 0][1] * x[lag][1];
109  phi[2-lag][1][1] = imag_sum + x[ 0][0] * x[lag][1] - x[ 0][1] * x[lag][0];
110  if (lag == 1) {
111  phi[0][0][0] = real_sum + x[38][0] * x[39][0] + x[38][1] * x[39][1];
112  phi[0][0][1] = imag_sum + x[38][0] * x[39][1] - x[38][1] * x[39][0];
113  }
114  } else {
115  for (i = 1; i < 38; i++) {
116  real_sum += x[i][0] * x[i][0] + x[i][1] * x[i][1];
117  }
118  phi[2][1][0] = real_sum + x[ 0][0] * x[ 0][0] + x[ 0][1] * x[ 0][1];
119  phi[1][0][0] = real_sum + x[38][0] * x[38][0] + x[38][1] * x[38][1];
120  }
121 }
122 
123 static void sbr_autocorrelate_c(const float x[40][2], float phi[3][2][2])
124 {
125  autocorrelate(x, phi, 0);
126  autocorrelate(x, phi, 1);
127  autocorrelate(x, phi, 2);
128 }
129 
130 static void sbr_hf_gen_c(float (*X_high)[2], const float (*X_low)[2],
131  const float alpha0[2], const float alpha1[2],
132  float bw, int start, int end)
133 {
134  float alpha[4];
135  int i;
136 
137  alpha[0] = alpha1[0] * bw * bw;
138  alpha[1] = alpha1[1] * bw * bw;
139  alpha[2] = alpha0[0] * bw;
140  alpha[3] = alpha0[1] * bw;
141 
142  for (i = start; i < end; i++) {
143  X_high[i][0] =
144  X_low[i - 2][0] * alpha[0] -
145  X_low[i - 2][1] * alpha[1] +
146  X_low[i - 1][0] * alpha[2] -
147  X_low[i - 1][1] * alpha[3] +
148  X_low[i][0];
149  X_high[i][1] =
150  X_low[i - 2][1] * alpha[0] +
151  X_low[i - 2][0] * alpha[1] +
152  X_low[i - 1][1] * alpha[2] +
153  X_low[i - 1][0] * alpha[3] +
154  X_low[i][1];
155  }
156 }
157 
158 static void sbr_hf_g_filt_c(float (*Y)[2], const float (*X_high)[40][2],
159  const float *g_filt, int m_max, intptr_t ixh)
160 {
161  int m;
162 
163  for (m = 0; m < m_max; m++) {
164  Y[m][0] = X_high[m][ixh][0] * g_filt[m];
165  Y[m][1] = X_high[m][ixh][1] * g_filt[m];
166  }
167 }
168 
169 static av_always_inline void sbr_hf_apply_noise(float (*Y)[2],
170  const float *s_m,
171  const float *q_filt,
172  int noise,
173  float phi_sign0,
174  float phi_sign1,
175  int m_max)
176 {
177  int m;
178 
179  for (m = 0; m < m_max; m++) {
180  float y0 = Y[m][0];
181  float y1 = Y[m][1];
182  noise = (noise + 1) & 0x1ff;
183  if (s_m[m]) {
184  y0 += s_m[m] * phi_sign0;
185  y1 += s_m[m] * phi_sign1;
186  } else {
187  y0 += q_filt[m] * ff_sbr_noise_table[noise][0];
188  y1 += q_filt[m] * ff_sbr_noise_table[noise][1];
189  }
190  Y[m][0] = y0;
191  Y[m][1] = y1;
192  phi_sign1 = -phi_sign1;
193  }
194 }
195 
196 static void sbr_hf_apply_noise_0(float (*Y)[2], const float *s_m,
197  const float *q_filt, int noise,
198  int kx, int m_max)
199 {
200  sbr_hf_apply_noise(Y, s_m, q_filt, noise, 1.0, 0.0, m_max);
201 }
202 
203 static void sbr_hf_apply_noise_1(float (*Y)[2], const float *s_m,
204  const float *q_filt, int noise,
205  int kx, int m_max)
206 {
207  float phi_sign = 1 - 2 * (kx & 1);
208  sbr_hf_apply_noise(Y, s_m, q_filt, noise, 0.0, phi_sign, m_max);
209 }
210 
211 static void sbr_hf_apply_noise_2(float (*Y)[2], const float *s_m,
212  const float *q_filt, int noise,
213  int kx, int m_max)
214 {
215  sbr_hf_apply_noise(Y, s_m, q_filt, noise, -1.0, 0.0, m_max);
216 }
217 
218 static void sbr_hf_apply_noise_3(float (*Y)[2], const float *s_m,
219  const float *q_filt, int noise,
220  int kx, int m_max)
221 {
222  float phi_sign = 1 - 2 * (kx & 1);
223  sbr_hf_apply_noise(Y, s_m, q_filt, noise, 0.0, -phi_sign, m_max);
224 }
225 
227 {
228  s->sum64x5 = sbr_sum64x5_c;
236  s->hf_gen = sbr_hf_gen_c;
238 
243 
244  if (ARCH_ARM)
246  if (ARCH_X86)
248 }