FFmpeg
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 FFmpeg.
7  *
8  * FFmpeg 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  * FFmpeg 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 FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 #define USE_FIXED 0
24 
25 #include "aac.h"
26 #include "config.h"
27 #include "libavutil/attributes.h"
28 #include "libavutil/intfloat.h"
29 #include "sbrdsp.h"
30 
31 static float sbr_sum_square_c(float (*x)[2], int n)
32 {
33  float sum0 = 0.0f, sum1 = 0.0f;
34  int i;
35 
36  for (i = 0; i < n; i += 2)
37  {
38  sum0 += x[i + 0][0] * x[i + 0][0];
39  sum1 += x[i + 0][1] * x[i + 0][1];
40  sum0 += x[i + 1][0] * x[i + 1][0];
41  sum1 += x[i + 1][1] * x[i + 1][1];
42  }
43 
44  return sum0 + sum1;
45 }
46 
47 static void sbr_neg_odd_64_c(float *x)
48 {
49  union av_intfloat32 *xi = (union av_intfloat32*) x;
50  int i;
51  for (i = 1; i < 64; i += 4) {
52  xi[i + 0].i ^= 1U << 31;
53  xi[i + 2].i ^= 1U << 31;
54  }
55 }
56 
57 static void sbr_qmf_pre_shuffle_c(float *z)
58 {
59  union av_intfloat32 *zi = (union av_intfloat32*) z;
60  int k;
61  zi[64].i = zi[0].i;
62  zi[65].i = zi[1].i;
63  for (k = 1; k < 31; k += 2) {
64  zi[64 + 2 * k + 0].i = zi[64 - k].i ^ (1U << 31);
65  zi[64 + 2 * k + 1].i = zi[ k + 1].i;
66  zi[64 + 2 * k + 2].i = zi[63 - k].i ^ (1U << 31);
67  zi[64 + 2 * k + 3].i = zi[ k + 2].i;
68  }
69 
70  zi[64 + 2 * 31 + 0].i = zi[64 - 31].i ^ (1U << 31);
71  zi[64 + 2 * 31 + 1].i = zi[31 + 1].i;
72 }
73 
74 static void sbr_qmf_post_shuffle_c(float W[32][2], const float *z)
75 {
76  const union av_intfloat32 *zi = (const union av_intfloat32*) z;
77  union av_intfloat32 *Wi = (union av_intfloat32*) W;
78  int k;
79  for (k = 0; k < 32; k += 2) {
80  Wi[2 * k + 0].i = zi[63 - k].i ^ (1U << 31);
81  Wi[2 * k + 1].i = zi[ k + 0].i;
82  Wi[2 * k + 2].i = zi[62 - k].i ^ (1U << 31);
83  Wi[2 * k + 3].i = zi[ k + 1].i;
84  }
85 }
86 
87 static void sbr_qmf_deint_neg_c(float *v, const float *src)
88 {
89  const union av_intfloat32 *si = (const union av_intfloat32*)src;
90  union av_intfloat32 *vi = (union av_intfloat32*)v;
91  int i;
92  for (i = 0; i < 32; i++) {
93  vi[ i].i = si[63 - 2 * i ].i;
94  vi[63 - i].i = si[63 - 2 * i - 1].i ^ (1U << 31);
95  }
96 }
97 
98 #if 0
99  /* This code is slower because it multiplies memory accesses.
100  * It is left for educational purposes and because it may offer
101  * a better reference for writing arch-specific DSP functions. */
102 static av_always_inline void autocorrelate(const float x[40][2],
103  float phi[3][2][2], int lag)
104 {
105  int i;
106  float real_sum = 0.0f;
107  float imag_sum = 0.0f;
108  if (lag) {
109  for (i = 1; i < 38; i++) {
110  real_sum += x[i][0] * x[i+lag][0] + x[i][1] * x[i+lag][1];
111  imag_sum += x[i][0] * x[i+lag][1] - x[i][1] * x[i+lag][0];
112  }
113  phi[2-lag][1][0] = real_sum + x[ 0][0] * x[lag][0] + x[ 0][1] * x[lag][1];
114  phi[2-lag][1][1] = imag_sum + x[ 0][0] * x[lag][1] - x[ 0][1] * x[lag][0];
115  if (lag == 1) {
116  phi[0][0][0] = real_sum + x[38][0] * x[39][0] + x[38][1] * x[39][1];
117  phi[0][0][1] = imag_sum + x[38][0] * x[39][1] - x[38][1] * x[39][0];
118  }
119  } else {
120  for (i = 1; i < 38; i++) {
121  real_sum += x[i][0] * x[i][0] + x[i][1] * x[i][1];
122  }
123  phi[2][1][0] = real_sum + x[ 0][0] * x[ 0][0] + x[ 0][1] * x[ 0][1];
124  phi[1][0][0] = real_sum + x[38][0] * x[38][0] + x[38][1] * x[38][1];
125  }
126 }
127 
128 static void sbr_autocorrelate_c(const float x[40][2], float phi[3][2][2])
129 {
130  autocorrelate(x, phi, 0);
131  autocorrelate(x, phi, 1);
132  autocorrelate(x, phi, 2);
133 }
134 #else
135 static void sbr_autocorrelate_c(const float x[40][2], float phi[3][2][2])
136 {
137  float real_sum2 = x[0][0] * x[2][0] + x[0][1] * x[2][1];
138  float imag_sum2 = x[0][0] * x[2][1] - x[0][1] * x[2][0];
139  float real_sum1 = 0.0f, imag_sum1 = 0.0f, real_sum0 = 0.0f;
140  int i;
141  for (i = 1; i < 38; i++) {
142  real_sum0 += x[i][0] * x[i ][0] + x[i][1] * x[i ][1];
143  real_sum1 += x[i][0] * x[i + 1][0] + x[i][1] * x[i + 1][1];
144  imag_sum1 += x[i][0] * x[i + 1][1] - x[i][1] * x[i + 1][0];
145  real_sum2 += x[i][0] * x[i + 2][0] + x[i][1] * x[i + 2][1];
146  imag_sum2 += x[i][0] * x[i + 2][1] - x[i][1] * x[i + 2][0];
147  }
148  phi[2 - 2][1][0] = real_sum2;
149  phi[2 - 2][1][1] = imag_sum2;
150  phi[2 ][1][0] = real_sum0 + x[ 0][0] * x[ 0][0] + x[ 0][1] * x[ 0][1];
151  phi[1 ][0][0] = real_sum0 + x[38][0] * x[38][0] + x[38][1] * x[38][1];
152  phi[2 - 1][1][0] = real_sum1 + x[ 0][0] * x[ 1][0] + x[ 0][1] * x[ 1][1];
153  phi[2 - 1][1][1] = imag_sum1 + x[ 0][0] * x[ 1][1] - x[ 0][1] * x[ 1][0];
154  phi[0 ][0][0] = real_sum1 + x[38][0] * x[39][0] + x[38][1] * x[39][1];
155  phi[0 ][0][1] = imag_sum1 + x[38][0] * x[39][1] - x[38][1] * x[39][0];
156 }
157 #endif
158 
159 static void sbr_hf_gen_c(float (*X_high)[2], const float (*X_low)[2],
160  const float alpha0[2], const float alpha1[2],
161  float bw, int start, int end)
162 {
163  float alpha[4];
164  int i;
165 
166  alpha[0] = alpha1[0] * bw * bw;
167  alpha[1] = alpha1[1] * bw * bw;
168  alpha[2] = alpha0[0] * bw;
169  alpha[3] = alpha0[1] * bw;
170 
171  for (i = start; i < end; i++) {
172  X_high[i][0] =
173  X_low[i - 2][0] * alpha[0] -
174  X_low[i - 2][1] * alpha[1] +
175  X_low[i - 1][0] * alpha[2] -
176  X_low[i - 1][1] * alpha[3] +
177  X_low[i][0];
178  X_high[i][1] =
179  X_low[i - 2][1] * alpha[0] +
180  X_low[i - 2][0] * alpha[1] +
181  X_low[i - 1][1] * alpha[2] +
182  X_low[i - 1][0] * alpha[3] +
183  X_low[i][1];
184  }
185 }
186 
187 static void sbr_hf_g_filt_c(float (*Y)[2], const float (*X_high)[40][2],
188  const float *g_filt, int m_max, intptr_t ixh)
189 {
190  int m;
191 
192  for (m = 0; m < m_max; m++) {
193  Y[m][0] = X_high[m][ixh][0] * g_filt[m];
194  Y[m][1] = X_high[m][ixh][1] * g_filt[m];
195  }
196 }
197 
198 static av_always_inline void sbr_hf_apply_noise(float (*Y)[2],
199  const float *s_m,
200  const float *q_filt,
201  int noise,
202  float phi_sign0,
203  float phi_sign1,
204  int m_max)
205 {
206  int m;
207 
208  for (m = 0; m < m_max; m++) {
209  float y0 = Y[m][0];
210  float y1 = Y[m][1];
211  noise = (noise + 1) & 0x1ff;
212  if (s_m[m]) {
213  y0 += s_m[m] * phi_sign0;
214  y1 += s_m[m] * phi_sign1;
215  } else {
216  y0 += q_filt[m] * ff_sbr_noise_table[noise][0];
217  y1 += q_filt[m] * ff_sbr_noise_table[noise][1];
218  }
219  Y[m][0] = y0;
220  Y[m][1] = y1;
221  phi_sign1 = -phi_sign1;
222  }
223 }
224 
225 #include "sbrdsp_template.c"
W
@ W
Definition: vf_addroi.c:26
av_intfloat32::i
uint32_t i
Definition: intfloat.h:28
intfloat.h
U
#define U(x)
Definition: vp56_arith.h:37
autocorrelate
static av_always_inline void autocorrelate(const int x[40][2], SoftFloat phi[3][2][2], int lag)
Definition: sbrdsp_fixed.c:146
sbr_hf_gen_c
static void sbr_hf_gen_c(float(*X_high)[2], const float(*X_low)[2], const float alpha0[2], const float alpha1[2], float bw, int start, int end)
Definition: sbrdsp.c:159
xi
#define xi(width, name, var, range_min, range_max, subs,...)
Definition: cbs_h2645.c:404
sbr_qmf_pre_shuffle_c
static void sbr_qmf_pre_shuffle_c(float *z)
Definition: sbrdsp.c:57
src
#define src
Definition: vp8dsp.c:255
aac.h
av_intfloat32
Definition: intfloat.h:27
sbr_qmf_deint_neg_c
static void sbr_qmf_deint_neg_c(float *v, const float *src)
Definition: sbrdsp.c:87
ff_sbr_noise_table
const INTFLOAT ff_sbr_noise_table[][2]
window coefficients for analysis/synthesis QMF banks
Definition: aacsbrdata.h:271
sbr_hf_apply_noise
static av_always_inline void sbr_hf_apply_noise(float(*Y)[2], const float *s_m, const float *q_filt, int noise, float phi_sign0, float phi_sign1, int m_max)
Definition: sbrdsp.c:198
sbrdsp.h
sbr_sum_square_c
static float sbr_sum_square_c(float(*x)[2], int n)
Definition: sbrdsp.c:31
attributes.h
sbr_autocorrelate_c
static void sbr_autocorrelate_c(const float x[40][2], float phi[3][2][2])
Definition: sbrdsp.c:135
Y
#define Y
Definition: boxblur.h:37
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:271
av_always_inline
#define av_always_inline
Definition: attributes.h:49
sbr_qmf_post_shuffle_c
static void sbr_qmf_post_shuffle_c(float W[32][2], const float *z)
Definition: sbrdsp.c:74
sbr_hf_g_filt_c
static void sbr_hf_g_filt_c(float(*Y)[2], const float(*X_high)[40][2], const float *g_filt, int m_max, intptr_t ixh)
Definition: sbrdsp.c:187
noise
static int noise(AVBSFContext *ctx, AVPacket *pkt)
Definition: noise_bsf.c:121
alpha
static const int16_t alpha[]
Definition: ilbcdata.h:55
sbrdsp_template.c
sbr_neg_odd_64_c
static void sbr_neg_odd_64_c(float *x)
Definition: sbrdsp.c:47