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sipr16k.c
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1 /*
2  * SIPR decoder for the 16k mode
3  *
4  * Copyright (c) 2008 Vladimir Voroshilov
5  * Copyright (c) 2009 Vitor Sessak
6  *
7  * This file is part of FFmpeg.
8  *
9  * FFmpeg is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU Lesser General Public
11  * License as published by the Free Software Foundation; either
12  * version 2.1 of the License, or (at your option) any later version.
13  *
14  * FFmpeg is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17  * Lesser General Public License for more details.
18  *
19  * You should have received a copy of the GNU Lesser General Public
20  * License along with FFmpeg; if not, write to the Free Software
21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22  */
23 
24 #include <math.h>
25 
26 #include "sipr.h"
27 #include "libavutil/attributes.h"
28 #include "libavutil/common.h"
29 #include "libavutil/float_dsp.h"
30 #include "libavutil/mathematics.h"
31 #include "lsp.h"
32 #include "celp_filters.h"
33 #include "acelp_vectors.h"
34 #include "acelp_pitch_delay.h"
35 #include "acelp_filters.h"
36 #include "celp_filters.h"
37 
38 #include "sipr16kdata.h"
39 
40 /**
41  * Convert an lsf vector into an lsp vector.
42  *
43  * @param lsf input lsf vector
44  * @param lsp output lsp vector
45  */
46 static void lsf2lsp(const float *lsf, double *lsp)
47 {
48  int i;
49 
50  for (i = 0; i < LP_FILTER_ORDER_16k; i++)
51  lsp[i] = cosf(lsf[i]);
52 }
53 
54 static void dequant(float *out, const int *idx, const float *cbs[])
55 {
56  int i;
57 
58  for (i = 0; i < 4; i++)
59  memcpy(out + 3*i, cbs[i] + 3*idx[i], 3*sizeof(float));
60 
61  memcpy(out + 12, cbs[4] + 4*idx[4], 4*sizeof(float));
62 }
63 
64 static void lsf_decode_fp_16k(float* lsf_history, float* isp_new,
65  const int* parm, int ma_pred)
66 {
67  int i;
68  float isp_q[LP_FILTER_ORDER_16k];
69 
70  dequant(isp_q, parm, lsf_codebooks_16k);
71 
72  for (i = 0; i < LP_FILTER_ORDER_16k; i++) {
73  isp_new[i] = (1 - qu[ma_pred]) * isp_q[i]
74  + qu[ma_pred] * lsf_history[i]
75  + mean_lsf_16k[i];
76  }
77 
78  memcpy(lsf_history, isp_q, LP_FILTER_ORDER_16k * sizeof(float));
79 }
80 
81 static int dec_delay3_1st(int index)
82 {
83  if (index < 390) {
84  return index + 88;
85  } else
86  return 3 * index - 690;
87 }
88 
89 static int dec_delay3_2nd(int index, int pit_min, int pit_max,
90  int pitch_lag_prev)
91 {
92  if (index < 62) {
93  int pitch_delay_min = av_clip(pitch_lag_prev - 10,
94  pit_min, pit_max - 19);
95  return 3 * pitch_delay_min + index - 2;
96  } else
97  return 3 * pitch_lag_prev;
98 }
99 
100 static void postfilter(float *out_data, float* synth, float* iir_mem,
101  float* filt_mem[2], float* mem_preemph)
102 {
103  float buf[30 + LP_FILTER_ORDER_16k];
104  float *tmpbuf = buf + LP_FILTER_ORDER_16k;
105  float s;
106  int i;
107 
108  for (i = 0; i < LP_FILTER_ORDER_16k; i++)
109  filt_mem[0][i] = iir_mem[i] * ff_pow_0_5[i];
110 
111  memcpy(tmpbuf - LP_FILTER_ORDER_16k, mem_preemph,
112  LP_FILTER_ORDER_16k*sizeof(*buf));
113 
114  ff_celp_lp_synthesis_filterf(tmpbuf, filt_mem[1], synth, 30,
115  LP_FILTER_ORDER_16k);
116 
117  memcpy(synth - LP_FILTER_ORDER_16k, mem_preemph,
118  LP_FILTER_ORDER_16k * sizeof(*synth));
119 
120  ff_celp_lp_synthesis_filterf(synth, filt_mem[0], synth, 30,
121  LP_FILTER_ORDER_16k);
122 
123  memcpy(out_data + 30 - LP_FILTER_ORDER_16k,
124  synth + 30 - LP_FILTER_ORDER_16k,
125  LP_FILTER_ORDER_16k * sizeof(*synth));
126 
127  ff_celp_lp_synthesis_filterf(out_data + 30, filt_mem[0],
128  synth + 30, 2 * L_SUBFR_16k - 30,
129  LP_FILTER_ORDER_16k);
130 
131 
132  memcpy(mem_preemph, out_data + 2*L_SUBFR_16k - LP_FILTER_ORDER_16k,
133  LP_FILTER_ORDER_16k * sizeof(*synth));
134 
135  FFSWAP(float *, filt_mem[0], filt_mem[1]);
136  for (i = 0, s = 0; i < 30; i++, s += 1.0/30)
137  out_data[i] = tmpbuf[i] + s * (synth[i] - tmpbuf[i]);
138 }
139 
140 /**
141  * Floating point version of ff_acelp_lp_decode().
142  */
143 static void acelp_lp_decodef(float *lp_1st, float *lp_2nd,
144  const double *lsp_2nd, const double *lsp_prev)
145 {
146  double lsp_1st[LP_FILTER_ORDER_16k];
147  int i;
148 
149  /* LSP values for first subframe (3.2.5 of G.729, Equation 24) */
150  for (i = 0; i < LP_FILTER_ORDER_16k; i++)
151  lsp_1st[i] = (lsp_2nd[i] + lsp_prev[i]) * 0.5;
152 
153  ff_acelp_lspd2lpc(lsp_1st, lp_1st, LP_FILTER_ORDER_16k >> 1);
154 
155  /* LSP values for second subframe (3.2.5 of G.729) */
156  ff_acelp_lspd2lpc(lsp_2nd, lp_2nd, LP_FILTER_ORDER_16k >> 1);
157 }
158 
159 /**
160  * Floating point version of ff_acelp_decode_gain_code().
161  */
162 static float acelp_decode_gain_codef(float gain_corr_factor, const float *fc_v,
163  float mr_energy, const float *quant_energy,
164  const float *ma_prediction_coeff,
165  int subframe_size, int ma_pred_order)
166 {
167  mr_energy += avpriv_scalarproduct_float_c(quant_energy, ma_prediction_coeff,
168  ma_pred_order);
169 
170  mr_energy = gain_corr_factor * exp(M_LN10 / 20. * mr_energy) /
171  sqrt((0.01 + avpriv_scalarproduct_float_c(fc_v, fc_v, subframe_size)));
172  return mr_energy;
173 }
174 
175 #define DIVIDE_BY_3(x) ((x) * 10923 >> 15)
176 
178  float *out_data)
179 {
181  float *synth = ctx->synth_buf + LP_FILTER_ORDER_16k;
182  float lsf_new[LP_FILTER_ORDER_16k];
183  double lsp_new[LP_FILTER_ORDER_16k];
184  float Az[2][LP_FILTER_ORDER_16k];
185  float fixed_vector[L_SUBFR_16k];
186  float pitch_fac, gain_code;
187 
188  int i;
189  int pitch_delay_3x;
190 
191  float *excitation = ctx->excitation + 292;
192 
193  lsf_decode_fp_16k(ctx->lsf_history, lsf_new, params->vq_indexes,
194  params->ma_pred_switch);
195 
197 
198  lsf2lsp(lsf_new, lsp_new);
199 
200  acelp_lp_decodef(Az[0], Az[1], lsp_new, ctx->lsp_history_16k);
201 
202  memcpy(ctx->lsp_history_16k, lsp_new, LP_FILTER_ORDER_16k * sizeof(double));
203 
204  memcpy(synth - LP_FILTER_ORDER_16k, ctx->synth,
205  LP_FILTER_ORDER_16k * sizeof(*synth));
206 
207  for (i = 0; i < SUBFRAME_COUNT_16k; i++) {
208  int i_subfr = i * L_SUBFR_16k;
209  AMRFixed f;
210  float gain_corr_factor;
211  int pitch_delay_int;
212  int pitch_delay_frac;
213 
214  if (!i) {
215  pitch_delay_3x = dec_delay3_1st(params->pitch_delay[i]);
216  } else
217  pitch_delay_3x = dec_delay3_2nd(params->pitch_delay[i],
219  ctx->pitch_lag_prev);
220 
221  pitch_fac = gain_pitch_cb_16k[params->gp_index[i]];
222  f.pitch_fac = FFMIN(pitch_fac, 1.0);
223  f.pitch_lag = DIVIDE_BY_3(pitch_delay_3x+1);
224  ctx->pitch_lag_prev = f.pitch_lag;
225 
226  pitch_delay_int = DIVIDE_BY_3(pitch_delay_3x + 2);
227  pitch_delay_frac = pitch_delay_3x + 2 - 3*pitch_delay_int;
228 
229  ff_acelp_interpolatef(&excitation[i_subfr],
230  &excitation[i_subfr] - pitch_delay_int + 1,
231  sinc_win, 3, pitch_delay_frac + 1,
232  LP_FILTER_ORDER, L_SUBFR_16k);
233 
234 
235  memset(fixed_vector, 0, sizeof(fixed_vector));
236 
237  ff_decode_10_pulses_35bits(params->fc_indexes[i], &f,
239 
240  ff_set_fixed_vector(fixed_vector, &f, 1.0, L_SUBFR_16k);
241 
242  gain_corr_factor = gain_cb_16k[params->gc_index[i]];
243  gain_code = gain_corr_factor *
244  acelp_decode_gain_codef(sqrt(L_SUBFR_16k), fixed_vector,
245  19.0 - 15.0/(0.05*M_LN10/M_LN2),
246  pred_16k, ctx->energy_history,
247  L_SUBFR_16k, 2);
248 
249  ctx->energy_history[1] = ctx->energy_history[0];
250  ctx->energy_history[0] = 20.0 * log10f(gain_corr_factor);
251 
252  ff_weighted_vector_sumf(&excitation[i_subfr], &excitation[i_subfr],
253  fixed_vector, pitch_fac,
254  gain_code, L_SUBFR_16k);
255 
256  ff_celp_lp_synthesis_filterf(synth + i_subfr, Az[i],
257  &excitation[i_subfr], L_SUBFR_16k,
259 
260  }
261  memcpy(ctx->synth, synth + frame_size - LP_FILTER_ORDER_16k,
262  LP_FILTER_ORDER_16k * sizeof(*synth));
263 
264  memmove(ctx->excitation, ctx->excitation + 2 * L_SUBFR_16k,
265  (L_INTERPOL+PITCH_MAX) * sizeof(float));
266 
267  postfilter(out_data, synth, ctx->iir_mem, ctx->filt_mem, ctx->mem_preemph);
268 
269  memcpy(ctx->iir_mem, Az[1], LP_FILTER_ORDER_16k * sizeof(float));
270 }
271 
273 {
274  int i;
275 
276  for (i = 0; i < LP_FILTER_ORDER_16k; i++)
277  ctx->lsp_history_16k[i] = cos((i + 1) * M_PI/(LP_FILTER_ORDER_16k + 1));
278 
279  ctx->filt_mem[0] = ctx->filt_buf[0];
280  ctx->filt_mem[1] = ctx->filt_buf[1];
281 
282  ctx->pitch_lag_prev = 180;
283 }