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sbrdsp_fixed.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  * Note: Rounding-to-nearest used unless otherwise stated
23  *
24  */
25 
26 #define USE_FIXED 1
27 
28 #include "aac.h"
29 #include "config.h"
30 #include "libavutil/attributes.h"
31 #include "libavutil/intfloat.h"
32 #include "sbrdsp.h"
33 
34 static SoftFloat sbr_sum_square_c(int (*x)[2], int n)
35 {
36  SoftFloat ret;
37  int64_t accu = 0;
38  int i, nz, round;
39 
40  for (i = 0; i < n; i += 2) {
41  // Larger values are inavlid and could cause overflows of accu.
42  av_assert2(FFABS(x[i + 0][0]) >> 29 == 0);
43  accu += (int64_t)x[i + 0][0] * x[i + 0][0];
44  av_assert2(FFABS(x[i + 0][1]) >> 29 == 0);
45  accu += (int64_t)x[i + 0][1] * x[i + 0][1];
46  av_assert2(FFABS(x[i + 1][0]) >> 29 == 0);
47  accu += (int64_t)x[i + 1][0] * x[i + 1][0];
48  av_assert2(FFABS(x[i + 1][1]) >> 29 == 0);
49  accu += (int64_t)x[i + 1][1] * x[i + 1][1];
50  }
51 
52  i = (int)(accu >> 32);
53  if (i == 0) {
54  nz = 1;
55  } else {
56  nz = 0;
57  while (FFABS(i) < 0x40000000) {
58  i <<= 1;
59  nz++;
60  }
61  nz = 32 - nz;
62  }
63 
64  round = 1 << (nz-1);
65  i = (int)((accu + round) >> nz);
66  i >>= 1;
67  ret = av_int2sf(i, 15 - nz);
68 
69  return ret;
70 }
71 
72 static void sbr_neg_odd_64_c(int *x)
73 {
74  int i;
75  for (i = 1; i < 64; i += 2)
76  x[i] = -x[i];
77 }
78 
79 static void sbr_qmf_pre_shuffle_c(int *z)
80 {
81  int k;
82  z[64] = z[0];
83  z[65] = z[1];
84  for (k = 1; k < 32; k++) {
85  z[64+2*k ] = -z[64 - k];
86  z[64+2*k+1] = z[ k + 1];
87  }
88 }
89 
90 static void sbr_qmf_post_shuffle_c(int W[32][2], const int *z)
91 {
92  int k;
93  for (k = 0; k < 32; k++) {
94  W[k][0] = -z[63-k];
95  W[k][1] = z[k];
96  }
97 }
98 
99 static void sbr_qmf_deint_neg_c(int *v, const int *src)
100 {
101  int i;
102  for (i = 0; i < 32; i++) {
103  v[ i] = ( src[63 - 2*i ] + 0x10) >> 5;
104  v[63 - i] = (-src[63 - 2*i - 1] + 0x10) >> 5;
105  }
106 }
107 
109 {
110  int nz, mant, expo, round;
111  int i = (int)(accu >> 32);
112  if (i == 0) {
113  nz = 1;
114  } else {
115  nz = 0;
116  while (FFABS(i) < 0x40000000) {
117  i <<= 1;
118  nz++;
119  }
120  nz = 32-nz;
121  }
122 
123  round = 1 << (nz-1);
124  mant = (int)((accu + round) >> nz);
125  mant = (mant + 0x40)>>7;
126  mant <<= 6;
127  expo = nz + 15;
128  return av_int2sf(mant, 30 - expo);
129 }
130 
131 static av_always_inline void autocorrelate(const int x[40][2], SoftFloat phi[3][2][2], int lag)
132 {
133  int i;
134  int64_t real_sum, imag_sum;
135  int64_t accu_re = 0, accu_im = 0;
136 
137  if (lag) {
138  for (i = 1; i < 38; i++) {
139  accu_re += (int64_t)x[i][0] * x[i+lag][0];
140  accu_re += (int64_t)x[i][1] * x[i+lag][1];
141  accu_im += (int64_t)x[i][0] * x[i+lag][1];
142  accu_im -= (int64_t)x[i][1] * x[i+lag][0];
143  }
144 
145  real_sum = accu_re;
146  imag_sum = accu_im;
147 
148  accu_re += (int64_t)x[ 0][0] * x[lag][0];
149  accu_re += (int64_t)x[ 0][1] * x[lag][1];
150  accu_im += (int64_t)x[ 0][0] * x[lag][1];
151  accu_im -= (int64_t)x[ 0][1] * x[lag][0];
152 
153  phi[2-lag][1][0] = autocorr_calc(accu_re);
154  phi[2-lag][1][1] = autocorr_calc(accu_im);
155 
156  if (lag == 1) {
157  accu_re = real_sum;
158  accu_im = imag_sum;
159  accu_re += (int64_t)x[38][0] * x[39][0];
160  accu_re += (int64_t)x[38][1] * x[39][1];
161  accu_im += (int64_t)x[38][0] * x[39][1];
162  accu_im -= (int64_t)x[38][1] * x[39][0];
163 
164  phi[0][0][0] = autocorr_calc(accu_re);
165  phi[0][0][1] = autocorr_calc(accu_im);
166  }
167  } else {
168  for (i = 1; i < 38; i++) {
169  accu_re += (int64_t)x[i][0] * x[i][0];
170  accu_re += (int64_t)x[i][1] * x[i][1];
171  }
172  real_sum = accu_re;
173  accu_re += (int64_t)x[ 0][0] * x[ 0][0];
174  accu_re += (int64_t)x[ 0][1] * x[ 0][1];
175 
176  phi[2][1][0] = autocorr_calc(accu_re);
177 
178  accu_re = real_sum;
179  accu_re += (int64_t)x[38][0] * x[38][0];
180  accu_re += (int64_t)x[38][1] * x[38][1];
181 
182  phi[1][0][0] = autocorr_calc(accu_re);
183  }
184 }
185 
186 static void sbr_autocorrelate_c(const int x[40][2], SoftFloat phi[3][2][2])
187 {
188  autocorrelate(x, phi, 0);
189  autocorrelate(x, phi, 1);
190  autocorrelate(x, phi, 2);
191 }
192 
193 static void sbr_hf_gen_c(int (*X_high)[2], const int (*X_low)[2],
194  const int alpha0[2], const int alpha1[2],
195  int bw, int start, int end)
196 {
197  int alpha[4];
198  int i;
199  int64_t accu;
200 
201  accu = (int64_t)alpha0[0] * bw;
202  alpha[2] = (int)((accu + 0x40000000) >> 31);
203  accu = (int64_t)alpha0[1] * bw;
204  alpha[3] = (int)((accu + 0x40000000) >> 31);
205  accu = (int64_t)bw * bw;
206  bw = (int)((accu + 0x40000000) >> 31);
207  accu = (int64_t)alpha1[0] * bw;
208  alpha[0] = (int)((accu + 0x40000000) >> 31);
209  accu = (int64_t)alpha1[1] * bw;
210  alpha[1] = (int)((accu + 0x40000000) >> 31);
211 
212  for (i = start; i < end; i++) {
213  accu = (int64_t)X_low[i][0] * 0x20000000;
214  accu += (int64_t)X_low[i - 2][0] * alpha[0];
215  accu -= (int64_t)X_low[i - 2][1] * alpha[1];
216  accu += (int64_t)X_low[i - 1][0] * alpha[2];
217  accu -= (int64_t)X_low[i - 1][1] * alpha[3];
218  X_high[i][0] = (int)((accu + 0x10000000) >> 29);
219 
220  accu = (int64_t)X_low[i][1] * 0x20000000;
221  accu += (int64_t)X_low[i - 2][1] * alpha[0];
222  accu += (int64_t)X_low[i - 2][0] * alpha[1];
223  accu += (int64_t)X_low[i - 1][1] * alpha[2];
224  accu += (int64_t)X_low[i - 1][0] * alpha[3];
225  X_high[i][1] = (int)((accu + 0x10000000) >> 29);
226  }
227 }
228 
229 static void sbr_hf_g_filt_c(int (*Y)[2], const int (*X_high)[40][2],
230  const SoftFloat *g_filt, int m_max, intptr_t ixh)
231 {
232  int m, r;
233  int64_t accu;
234 
235  for (m = 0; m < m_max; m++) {
236  r = 1 << (22-g_filt[m].exp);
237  accu = (int64_t)X_high[m][ixh][0] * ((g_filt[m].mant + 0x40)>>7);
238  Y[m][0] = (int)((accu + r) >> (23-g_filt[m].exp));
239 
240  accu = (int64_t)X_high[m][ixh][1] * ((g_filt[m].mant + 0x40)>>7);
241  Y[m][1] = (int)((accu + r) >> (23-g_filt[m].exp));
242  }
243 }
244 
245 static av_always_inline void sbr_hf_apply_noise(int (*Y)[2],
246  const SoftFloat *s_m,
247  const SoftFloat *q_filt,
248  int noise,
249  int phi_sign0,
250  int phi_sign1,
251  int m_max)
252 {
253  int m;
254 
255  for (m = 0; m < m_max; m++) {
256  int y0 = Y[m][0];
257  int y1 = Y[m][1];
258  noise = (noise + 1) & 0x1ff;
259  if (s_m[m].mant) {
260  int shift, round;
261 
262  shift = 22 - s_m[m].exp;
263  if (shift < 30) {
264  round = 1 << (shift-1);
265  y0 += (s_m[m].mant * phi_sign0 + round) >> shift;
266  y1 += (s_m[m].mant * phi_sign1 + round) >> shift;
267  }
268  } else {
269  int shift, round, tmp;
270  int64_t accu;
271 
272  shift = 22 - q_filt[m].exp;
273  if (shift < 30) {
274  round = 1 << (shift-1);
275 
276  accu = (int64_t)q_filt[m].mant * ff_sbr_noise_table_fixed[noise][0];
277  tmp = (int)((accu + 0x40000000) >> 31);
278  y0 += (tmp + round) >> shift;
279 
280  accu = (int64_t)q_filt[m].mant * ff_sbr_noise_table_fixed[noise][1];
281  tmp = (int)((accu + 0x40000000) >> 31);
282  y1 += (tmp + round) >> shift;
283  }
284  }
285  Y[m][0] = y0;
286  Y[m][1] = y1;
287  phi_sign1 = -phi_sign1;
288  }
289 }
290 
291 #include "sbrdsp_template.c"
static int shift(int a, int b)
Definition: sonic.c:82
static int noise(AVBSFContext *ctx, AVPacket *out)
Definition: noise_bsf.c:37
static av_always_inline SoftFloat autocorr_calc(int64_t accu)
Definition: sbrdsp_fixed.c:108
static void sbr_autocorrelate_c(const int x[40][2], SoftFloat phi[3][2][2])
Definition: sbrdsp_fixed.c:186
Macro definitions for various function/variable attributes.
#define av_assert2(cond)
assert() equivalent, that does lie in speed critical code.
Definition: avassert.h:63
static void sbr_hf_g_filt_c(int(*Y)[2], const int(*X_high)[40][2], const SoftFloat *g_filt, int m_max, intptr_t ixh)
Definition: sbrdsp_fixed.c:229
#define Y
Definition: vf_boxblur.c:76
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:90
int32_t mant
Definition: softfloat.h:35
unsigned m
Definition: audioconvert.c:187
static SoftFloat sbr_sum_square_c(int(*x)[2], int n)
Definition: sbrdsp_fixed.c:34
static double alpha(void *priv, double x, double y)
Definition: vf_geq.c:99
static av_always_inline void autocorrelate(const int x[40][2], SoftFloat phi[3][2][2], int lag)
Definition: sbrdsp_fixed.c:131
const char * r
Definition: vf_curves.c:107
static av_always_inline av_const double round(double x)
Definition: libm.h:444
static void sbr_qmf_post_shuffle_c(int W[32][2], const int *z)
Definition: sbrdsp_fixed.c:90
static av_always_inline void sbr_hf_apply_noise(int(*Y)[2], const SoftFloat *s_m, const SoftFloat *q_filt, int noise, int phi_sign0, int phi_sign1, int m_max)
Definition: sbrdsp_fixed.c:245
#define FFABS(a)
Absolute value, Note, INT_MIN / INT64_MIN result in undefined behavior as they are not representable ...
Definition: common.h:72
AAC definitions and structures.
int n
Definition: avisynth_c.h:547
#define src
Definition: vp9dsp.c:530
static void sbr_neg_odd_64_c(int *x)
Definition: sbrdsp_fixed.c:72
#define W(a, i, v)
Definition: jpegls.h:122
static void sbr_qmf_pre_shuffle_c(int *z)
Definition: sbrdsp_fixed.c:79
int32_t exp
Definition: softfloat.h:36
static uint8_t tmp[8]
Definition: des.c:38
static void sbr_qmf_deint_neg_c(int *v, const int *src)
Definition: sbrdsp_fixed.c:99
static av_const SoftFloat av_int2sf(int v, int frac_bits)
Converts a mantisse and exponent to a SoftFloat.
Definition: softfloat.h:176
void INT64 start
Definition: avisynth_c.h:553
#define av_always_inline
Definition: attributes.h:39
static void sbr_hf_gen_c(int(*X_high)[2], const int(*X_low)[2], const int alpha0[2], const int alpha1[2], int bw, int start, int end)
Definition: sbrdsp_fixed.c:193