xref: /aosp_15_r20/external/libxaac/encoder/ixheaace_cplx_pred.c (revision 15dc779a375ca8b5125643b829a8aa4b70d7f451)
1 /******************************************************************************
2  *                                                                            *
3  * Copyright (C) 2023 The Android Open Source Project
4  *
5  * Licensed under the Apache License, Version 2.0 (the "License");
6  * you may not use this file except in compliance with the License.
7  * You may obtain a copy of the License at:
8  *
9  * http://www.apache.org/licenses/LICENSE-2.0
10  *
11  * Unless required by applicable law or agreed to in writing, software
12  * distributed under the License is distributed on an "AS IS" BASIS,
13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14  * See the License for the specific language governing permissions and
15  * limitations under the License.
16  *
17  *****************************************************************************
18  * Originally developed and contributed by Ittiam Systems Pvt. Ltd, Bangalore
19  */
20 
21 #include <math.h>
22 #include <string.h>
23 #include <float.h>
24 #include "iusace_type_def.h"
25 #include "ixheaac_error_standards.h"
26 #include "ixheaace_error_codes.h"
27 #include "ixheaace_mps_common_define.h"
28 #include "iusace_cnst.h"
29 #include "iusace_fd_quant.h"
30 #include "iusace_bitbuffer.h"
31 #include "impd_drc_common_enc.h"
32 #include "impd_drc_uni_drc.h"
33 #include "impd_drc_api.h"
34 #include "impd_drc_uni_drc_eq.h"
35 #include "impd_drc_uni_drc_filter_bank.h"
36 #include "impd_drc_gain_enc.h"
37 #include "impd_drc_struct_def.h"
38 
39 #include "ixheaace_memory_standards.h"
40 #include "iusace_tns_usac.h"
41 #include "iusace_psy_mod.h"
42 #include "iusace_config.h"
43 #include "iusace_block_switch_const.h"
44 #include "iusace_block_switch_struct_def.h"
45 #include "iusace_signal_classifier.h"
46 #include "iusace_ms.h"
47 #include "ixheaace_adjust_threshold_data.h"
48 #include "iusace_fd_qc_util.h"
49 #include "ixheaace_sbr_header.h"
50 #include "ixheaace_config.h"
51 #include "ixheaace_asc_write.h"
52 #include "iusace_main.h"
53 #include "iusace_rom.h"
54 #include "ixheaace_common_utils.h"
55 
iusace_compute_pred_coef(WORD32 num_lines,WORD32 complex_coef,FLOAT64 * ptr_spec_mdct_dmx,FLOAT64 * ptr_spec_mdst_dmx,FLOAT64 * ptr_spec_mdct_mid_side,FLOAT32 * pred_coef_re,FLOAT32 * pred_coef_im,FLOAT32 * pred_coef_q_re,FLOAT32 * pred_coef_q_im,WORD32 * pred_coef_q_int_re,WORD32 * pred_coef_q_int_im)56 static VOID iusace_compute_pred_coef(WORD32 num_lines, WORD32 complex_coef,
57                                      FLOAT64 *ptr_spec_mdct_dmx, FLOAT64 *ptr_spec_mdst_dmx,
58                                      FLOAT64 *ptr_spec_mdct_mid_side, FLOAT32 *pred_coef_re,
59                                      FLOAT32 *pred_coef_im, FLOAT32 *pred_coef_q_re,
60                                      FLOAT32 *pred_coef_q_im, WORD32 *pred_coef_q_int_re,
61                                      WORD32 *pred_coef_q_int_im) {
62   LOOPIDX bin_idx;
63   FLOAT32 iprod_re = 0.0f, iprod_im = 0.0f;
64   FLOAT32 eps = 1.0e-6f;
65   const FLOAT32 k_delta = 0.1f;
66   const FLOAT32 k_max = 3.0f;
67   WORD32 pred_coef_sign_re, pred_coef_sign_im;
68   FLOAT32 pred_coef_abs_re, pred_coef_abs_im;
69   FLOAT32 abs_dmx = 0.0f;
70 
71   for (bin_idx = 0; bin_idx < num_lines; bin_idx++) {
72     /* D = Dr + jDi */
73     /* D*S = (Dr + jDi)*S = Dr*S + j(Di*S) */
74     /* alpha = alpha_r - jalpha_i */
75     if (complex_coef == 1) {
76       iprod_re += (FLOAT32)(ptr_spec_mdct_dmx[bin_idx] * ptr_spec_mdct_mid_side[bin_idx]);
77       iprod_im += (FLOAT32)(ptr_spec_mdst_dmx[bin_idx] * ptr_spec_mdct_mid_side[bin_idx]);
78       abs_dmx += (FLOAT32)(ptr_spec_mdct_dmx[bin_idx] * ptr_spec_mdct_dmx[bin_idx] +
79                            ptr_spec_mdst_dmx[bin_idx] * ptr_spec_mdst_dmx[bin_idx]);
80     } else {
81       iprod_re += (FLOAT32)(ptr_spec_mdct_dmx[bin_idx] * ptr_spec_mdct_mid_side[bin_idx]);
82       abs_dmx += (FLOAT32)(ptr_spec_mdct_dmx[bin_idx] * ptr_spec_mdct_dmx[bin_idx]);
83     }
84   }
85 
86   /* Compute real and imaginary parts of prediction coefficient  */
87   *pred_coef_re = iprod_re / (abs_dmx + eps);
88   pred_coef_sign_re = *pred_coef_re > 0 ? 1 : -1;
89   pred_coef_abs_re = (FLOAT32)MIN(fabs(*pred_coef_re), k_max);
90   *pred_coef_q_int_re = pred_coef_sign_re * (WORD32)(pred_coef_abs_re / k_delta + 0.5f);
91   *pred_coef_q_re = *pred_coef_q_int_re * k_delta;
92 
93   if (complex_coef == 1) {
94     *pred_coef_im = iprod_im / (abs_dmx + eps);
95     pred_coef_sign_im = *pred_coef_im > 0 ? 1 : -1;
96     pred_coef_abs_im = (FLOAT32)MIN(fabs(*pred_coef_im), k_max);
97     *pred_coef_q_int_im = pred_coef_sign_im * (WORD32)(pred_coef_abs_im / k_delta + 0.5f);
98     *pred_coef_q_im = *pred_coef_q_int_im * k_delta;
99   }
100 }
101 
iusace_compute_res(WORD32 num_lines,WORD32 complex_coef,FLOAT32 pred_coef_q_re,FLOAT32 pred_coef_q_im,FLOAT64 * ptr_spec_mdct_dmx,FLOAT64 * ptr_spec_mdst_dmx,FLOAT64 * ptr_spec_mdct_mid_side,FLOAT64 * ptr_spec_mdct_res)102 static VOID iusace_compute_res(WORD32 num_lines, WORD32 complex_coef, FLOAT32 pred_coef_q_re,
103                                FLOAT32 pred_coef_q_im, FLOAT64 *ptr_spec_mdct_dmx,
104                                FLOAT64 *ptr_spec_mdst_dmx, FLOAT64 *ptr_spec_mdct_mid_side,
105                                FLOAT64 *ptr_spec_mdct_res) {
106   LOOPIDX i;
107 
108   for (i = 0; i < num_lines; i++) {
109     /* DMX = M; E = S - alpha*DMX if pred_dir = 0 */
110     /* DMX = S; E = M - alpha*DMX if pred_dir = 1 */
111     if (complex_coef == 1) {
112       ptr_spec_mdct_res[i] =
113           (FLOAT32)(ptr_spec_mdct_mid_side[i] - pred_coef_q_re * ptr_spec_mdct_dmx[i] -
114                     pred_coef_q_im * ptr_spec_mdst_dmx[i]);
115     } else {
116       ptr_spec_mdct_res[i] =
117           (FLOAT32)(ptr_spec_mdct_mid_side[i] - pred_coef_q_re * ptr_spec_mdct_dmx[i]);
118     }
119   }
120 }
121 
iusace_filter_and_add(const FLOAT64 * ptr_in,const WORD32 length,const FLOAT64 * ptr_filter,FLOAT64 * ptr_out,const WORD32 factor_even)122 static VOID iusace_filter_and_add(const FLOAT64 *ptr_in, const WORD32 length,
123                                   const FLOAT64 *ptr_filter, FLOAT64 *ptr_out,
124                                   const WORD32 factor_even) {
125   LOOPIDX i;
126   FLOAT64 s;
127 
128   i = 0;
129   s = ptr_filter[6] * ptr_in[2] + ptr_filter[5] * ptr_in[1] + ptr_filter[4] * ptr_in[0] +
130       ptr_filter[3] * ptr_in[0] + ptr_filter[2] * ptr_in[1] + ptr_filter[1] * ptr_in[2] +
131       ptr_filter[0] * ptr_in[3];
132   ptr_out[i] += s * factor_even;
133   i = 1;
134   s = ptr_filter[6] * ptr_in[1] + ptr_filter[5] * ptr_in[0] + ptr_filter[4] * ptr_in[0] +
135       ptr_filter[3] * ptr_in[1] + ptr_filter[2] * ptr_in[2] + ptr_filter[1] * ptr_in[3] +
136       ptr_filter[0] * ptr_in[4];
137   ptr_out[i] += s;
138   i = 2;
139   s = ptr_filter[6] * ptr_in[0] + ptr_filter[5] * ptr_in[0] + ptr_filter[4] * ptr_in[1] +
140       ptr_filter[3] * ptr_in[2] + ptr_filter[2] * ptr_in[3] + ptr_filter[1] * ptr_in[4] +
141       ptr_filter[0] * ptr_in[5];
142   ptr_out[i] += s * factor_even;
143 
144   for (i = 3; i < length - 4; i += 2) {
145     s = ptr_filter[6] * ptr_in[i - 3] + ptr_filter[5] * ptr_in[i - 2] +
146         ptr_filter[4] * ptr_in[i - 1] + ptr_filter[3] * ptr_in[i] +
147         ptr_filter[2] * ptr_in[i + 1] + ptr_filter[1] * ptr_in[i + 2] +
148         ptr_filter[0] * ptr_in[i + 3];
149     ptr_out[i] += s;
150     s = ptr_filter[6] * ptr_in[i - 2] + ptr_filter[5] * ptr_in[i - 1] +
151         ptr_filter[4] * ptr_in[i] + ptr_filter[3] * ptr_in[i + 1] +
152         ptr_filter[2] * ptr_in[i + 2] + ptr_filter[1] * ptr_in[i + 3] +
153         ptr_filter[0] * ptr_in[i + 4];
154     ptr_out[i + 1] += s * factor_even;
155   }
156 
157   i = length - 3;
158   s = ptr_filter[6] * ptr_in[i - 3] + ptr_filter[5] * ptr_in[i - 2] +
159       ptr_filter[4] * ptr_in[i - 1] + ptr_filter[3] * ptr_in[i] + ptr_filter[2] * ptr_in[i + 1] +
160       ptr_filter[1] * ptr_in[i + 2] + ptr_filter[0] * ptr_in[i + 2];
161   ptr_out[i] += s;
162   i = length - 2;
163   s = ptr_filter[6] * ptr_in[i - 3] + ptr_filter[5] * ptr_in[i - 2] +
164       ptr_filter[4] * ptr_in[i - 1] + ptr_filter[3] * ptr_in[i] + ptr_filter[2] * ptr_in[i + 1] +
165       ptr_filter[1] * ptr_in[i + 1] + ptr_filter[0] * ptr_in[i];
166   ptr_out[i] += s * factor_even;
167   i = length - 1;
168   s = ptr_filter[6] * ptr_in[i - 3] + ptr_filter[5] * ptr_in[i - 2] +
169       ptr_filter[4] * ptr_in[i - 1] + ptr_filter[3] * ptr_in[i] + ptr_filter[2] * ptr_in[i] +
170       ptr_filter[1] * ptr_in[i - 1] + ptr_filter[0] * ptr_in[i - 2];
171   ptr_out[i] += s;
172 }
173 
iusace_estimate_dmx_im(const FLOAT64 * ptr_dmx_re,const FLOAT64 * ptr_dmx_re_prev,FLOAT64 * ptr_dmx_im,WORD32 window,const WORD32 w_shape,const WORD32 prev_w_shape,WORD32 num_sbk,WORD32 bins_per_sbk)174 static VOID iusace_estimate_dmx_im(const FLOAT64 *ptr_dmx_re, const FLOAT64 *ptr_dmx_re_prev,
175                                    FLOAT64 *ptr_dmx_im, WORD32 window, const WORD32 w_shape,
176                                    const WORD32 prev_w_shape, WORD32 num_sbk,
177                                    WORD32 bins_per_sbk) {
178   LOOPIDX i;
179   const FLOAT64 *ptr_mdst_fcoeff_curr, *ptr_mdst_fcoeff_prev;
180 
181   switch (window) {
182     case ONLY_LONG_SEQUENCE:
183     case EIGHT_SHORT_SEQUENCE:
184       ptr_mdst_fcoeff_curr = iusace_mdst_fcoeff_longshort_curr[prev_w_shape][w_shape];
185       ptr_mdst_fcoeff_prev = iusace_mdst_fcoeff_l_s_start_left_prev[prev_w_shape];
186       break;
187     case LONG_START_SEQUENCE:
188       ptr_mdst_fcoeff_curr = iusace_mdst_fcoeff_start_curr[prev_w_shape][w_shape];
189       ptr_mdst_fcoeff_prev = iusace_mdst_fcoeff_l_s_start_left_prev[prev_w_shape];
190       break;
191     case LONG_STOP_SEQUENCE:
192       ptr_mdst_fcoeff_curr = iusace_mdst_fcoeff_stop_cur[prev_w_shape][w_shape];
193       ptr_mdst_fcoeff_prev = iusace_mdst_fcoeff_stop_stopstart_left_prev[prev_w_shape];
194       break;
195     case STOP_START_SEQUENCE:
196       ptr_mdst_fcoeff_curr = iusace_mdst_fcoeff_stopstart_cur[prev_w_shape][w_shape];
197       ptr_mdst_fcoeff_prev = iusace_mdst_fcoeff_stop_stopstart_left_prev[prev_w_shape];
198       break;
199     default:
200       ptr_mdst_fcoeff_curr = iusace_mdst_fcoeff_stopstart_cur[prev_w_shape][w_shape];
201       ptr_mdst_fcoeff_prev = iusace_mdst_fcoeff_stop_stopstart_left_prev[prev_w_shape];
202       break;
203   }
204 
205   for (i = 0; i < num_sbk; i++) {
206     iusace_filter_and_add(ptr_dmx_re, bins_per_sbk, ptr_mdst_fcoeff_curr, ptr_dmx_im, 1);
207 
208     if (ptr_dmx_re_prev) {
209       iusace_filter_and_add(ptr_dmx_re_prev, bins_per_sbk, ptr_mdst_fcoeff_prev, ptr_dmx_im, -1);
210     }
211 
212     ptr_dmx_re_prev = ptr_dmx_re;
213     ptr_dmx_re += bins_per_sbk;
214     ptr_dmx_im += bins_per_sbk;
215   }
216   return;
217 }
218 
iusace_usac_cplx_save_prev(FLOAT64 * ptr_mdct_spec,FLOAT64 * ptr_mdct_spec_prev,WORD32 save_zeros,WORD32 condition_2,WORD32 samp_per_bk,WORD32 bins_per_sbk)219 static VOID iusace_usac_cplx_save_prev(FLOAT64 *ptr_mdct_spec, FLOAT64 *ptr_mdct_spec_prev,
220                                        WORD32 save_zeros, WORD32 condition_2, WORD32 samp_per_bk,
221                                        WORD32 bins_per_sbk) {
222   WORD32 offset;
223 
224   offset = samp_per_bk - bins_per_sbk;
225 
226   if (save_zeros || condition_2) {
227     memset(ptr_mdct_spec_prev + offset, 0, sizeof(FLOAT64) * bins_per_sbk);
228   } else {
229     memcpy(ptr_mdct_spec_prev + offset, ptr_mdct_spec + offset, sizeof(FLOAT64) * bins_per_sbk);
230   }
231   return;
232 }
233 
iusace_compute_ipd(FLOAT64 * ptr_spec_real1,FLOAT64 * ptr_spec_imag1,FLOAT64 * ptr_spec_real2,FLOAT64 * ptr_spec_imag2,WORD32 num_lines)234 static FLOAT64 iusace_compute_ipd(FLOAT64 *ptr_spec_real1, FLOAT64 *ptr_spec_imag1,
235                                   FLOAT64 *ptr_spec_real2, FLOAT64 *ptr_spec_imag2,
236                                   WORD32 num_lines) {
237   LOOPIDX i;
238 
239   FLOAT64 ipd = 0.0f;
240   FLOAT64 cross_corr_real = 0.0f, cross_corr_imag = 0.0f;
241 
242   for (i = 0; i < num_lines; i++) {
243     cross_corr_real +=
244         ptr_spec_real1[i] * ptr_spec_real2[i] + ptr_spec_imag1[i] * ptr_spec_imag2[i];
245     cross_corr_imag +=
246         -ptr_spec_imag2[i] * ptr_spec_real1[i] + ptr_spec_imag1[i] * ptr_spec_real2[i];
247   }
248 
249   ipd = (FLOAT64)atan2(cross_corr_imag, cross_corr_real);
250   ipd = ipd > 0 ? ipd : 2. * PI + ipd;
251 
252   return ipd;
253 }
254 
iusace_cplx_pred_main(WORD32 num_sfb,WORD32 num_window_groups,FLOAT64 * ptr_spec_mdct_mid,FLOAT64 * ptr_spec_mdct_side,WORD32 pred_coef_q_int_re[MAX_SHORT_WINDOWS][MAX_SFB_LONG],WORD32 pred_coef_q_int_im[MAX_SHORT_WINDOWS][MAX_SFB_LONG],WORD32 * pred_dir,ia_usac_data_struct * pstr_usac_data,ia_sfb_params_struct * pstr_sfb_prms,WORD32 usac_independancy_flag,ia_usac_encoder_config_struct * pstr_usac_config,FLOAT64 * ptr_scratch_cmpx_mdct_buf,WORD32 cplx_pred_used[MAX_SHORT_WINDOWS][MAX_SFB_LONG],WORD32 chn,const WORD32 * ptr_sfb_offsets,FLOAT32 nrg_mid,FLOAT32 nrg_side,WORD32 * ms_mask_flag)255 static IA_ERRORCODE iusace_cplx_pred_main(
256     WORD32 num_sfb, WORD32 num_window_groups, FLOAT64 *ptr_spec_mdct_mid,
257     FLOAT64 *ptr_spec_mdct_side, WORD32 pred_coef_q_int_re[MAX_SHORT_WINDOWS][MAX_SFB_LONG],
258     WORD32 pred_coef_q_int_im[MAX_SHORT_WINDOWS][MAX_SFB_LONG], WORD32 *pred_dir,
259     ia_usac_data_struct *pstr_usac_data, ia_sfb_params_struct *pstr_sfb_prms,
260     WORD32 usac_independancy_flag, ia_usac_encoder_config_struct *pstr_usac_config,
261     FLOAT64 *ptr_scratch_cmpx_mdct_buf, WORD32 cplx_pred_used[MAX_SHORT_WINDOWS][MAX_SFB_LONG],
262     WORD32 chn, const WORD32 *ptr_sfb_offsets, FLOAT32 nrg_mid, FLOAT32 nrg_side,
263     WORD32 *ms_mask_flag) {
264   LOOPIDX group, sfb, i;
265   FLOAT32 pred_coef_re, pred_coef_im, pred_coef_q_re, pred_coef_q_im = 0.0f;
266   const WORD32 sfb_per_pred_band = 2;
267   WORD32 left = 0, right = 0, save_zeros = 0, condition_2 = 0, samp_per_bk = 0, bins_per_sbk = 0,
268          num_sbk = 0;
269   FLOAT64 *ptr_dmx_re_prev;
270   FLOAT64 *ptr_spec_mdct_res = &ptr_scratch_cmpx_mdct_buf[0];
271   const WORD32 sfb_count = num_window_groups * num_sfb;
272   const WORD32 sfb_per_group = num_sfb;
273   WORD32 sfb_offsets = 0, zero_flag, spec_start, spec_end;
274 
275   left = chn, right = chn + 1;
276 
277   /* Number of sub-blocks */
278   if (pstr_usac_config->window_sequence[left] == EIGHT_SHORT_SEQUENCE) {
279     num_sbk = MAX_SHORT_WINDOWS;
280   }
281   if (pstr_usac_config->window_sequence[left] == ONLY_LONG_SEQUENCE ||
282       pstr_usac_config->window_sequence[left] == LONG_START_SEQUENCE ||
283       pstr_usac_config->window_sequence[left] == LONG_STOP_SEQUENCE ||
284       pstr_usac_config->window_sequence[left] == STOP_START_SEQUENCE) {
285     num_sbk = 1;
286   }
287 
288   if (num_sbk == 0) {
289     return IA_EXHEAACE_EXE_FATAL_USAC_INVALID_NUM_SBK;
290   }
291 
292   samp_per_bk = pstr_usac_config->ccfl;
293   bins_per_sbk = samp_per_bk / num_sbk;
294 
295   /* Compute prediction direction */
296   if (nrg_mid >= nrg_side) {
297     *pred_dir = 0;
298   } else {
299     *pred_dir = 1;
300   }
301 
302   if (pstr_usac_data->complex_coef[chn] == 1) {
303     save_zeros = ((pstr_usac_config->window_sequence[left] == EIGHT_SHORT_SEQUENCE &&
304                    pstr_usac_config->window_sequence[right] != EIGHT_SHORT_SEQUENCE) ||
305                   (pstr_usac_config->window_sequence[left] != EIGHT_SHORT_SEQUENCE &&
306                    pstr_usac_config->window_sequence[right] == EIGHT_SHORT_SEQUENCE));
307 
308     condition_2 = (usac_independancy_flag || pstr_usac_data->core_mode_prev[left] ||
309                    pstr_usac_data->core_mode_prev[right]);
310 
311     /* Compute current frame's MDST down-mix*/
312     ptr_dmx_re_prev = !(usac_independancy_flag) ? pstr_usac_data->ptr_dmx_re_save[chn] : NULL;
313 
314     memset(pstr_usac_data->ptr_dmx_im[chn], 0, sizeof(FLOAT64) * FRAME_LEN_LONG);
315 
316     iusace_estimate_dmx_im(*pred_dir == 0 ? ptr_spec_mdct_mid : ptr_spec_mdct_side,
317                            ptr_dmx_re_prev, pstr_usac_data->ptr_dmx_im[chn],
318                            pstr_usac_config->window_sequence[left],
319                            pstr_sfb_prms->window_shape[left],
320                            pstr_usac_config->window_shape_prev[left], num_sbk, bins_per_sbk);
321 
322     /* MCLT of downmix = dmx_re + j*dmx_im */
323     /*  Save MDCT down-mix for use as previous frame MDCT down-mix in the next frame */
324     iusace_usac_cplx_save_prev(*pred_dir == 0 ? &ptr_spec_mdct_mid[0] : &ptr_spec_mdct_side[0],
325                                pstr_usac_data->ptr_dmx_re_save[chn], save_zeros, condition_2,
326                                samp_per_bk, bins_per_sbk);
327   }
328 
329   /* Reset buffer to zero */
330   for (group = 0; group < MAX_SHORT_WINDOWS; group++) {
331     memset(pred_coef_q_int_re, 0, MAX_SFB_LONG * sizeof(WORD32));
332     memset(pred_coef_q_int_im, 0, MAX_SFB_LONG * sizeof(WORD32));
333   }
334 
335   group = 0;
336   for (sfb = 0; sfb < sfb_count; sfb += sfb_per_group, group++) {
337     for (sfb_offsets = 0; sfb_offsets < sfb_per_group; sfb_offsets += sfb_per_pred_band) {
338       if (cplx_pred_used[group][sfb_offsets] == 1) {
339         zero_flag = (ptr_sfb_offsets[sfb + sfb_offsets + 1] != FRAME_LEN_LONG);
340         spec_start = ptr_sfb_offsets[sfb + sfb_offsets];
341         spec_end = (zero_flag ? ptr_sfb_offsets[sfb + sfb_offsets + 2]
342                               : ptr_sfb_offsets[sfb + sfb_offsets + 1]);
343 
344         /* Calculate prediction coefficients */
345         iusace_compute_pred_coef(
346             spec_end - spec_start, pstr_usac_data->complex_coef[chn],
347             *pred_dir == 0 ? &ptr_spec_mdct_mid[spec_start] : &ptr_spec_mdct_side[spec_start],
348             pstr_usac_data->complex_coef[chn] == 1 ? &pstr_usac_data->ptr_dmx_im[chn][spec_start]
349                                                    : NULL,
350             *pred_dir == 0 ? &ptr_spec_mdct_side[spec_start] : &ptr_spec_mdct_mid[spec_start],
351             &pred_coef_re, pstr_usac_data->complex_coef[chn] == 1 ? &pred_coef_im : NULL,
352             &pred_coef_q_re, pstr_usac_data->complex_coef[chn] == 1 ? &pred_coef_q_im : NULL,
353             &pred_coef_q_int_re[group][sfb_offsets],
354             pstr_usac_data->complex_coef[chn] == 1 ? &pred_coef_q_int_im[group][sfb_offsets]
355                                                    : NULL);
356 
357         /* Calculate residual */
358         iusace_compute_res(
359             spec_end - spec_start, pstr_usac_data->complex_coef[chn], pred_coef_q_re,
360             pstr_usac_data->complex_coef[chn] == 1 ? pred_coef_q_im : 0,
361             *pred_dir == 0 ? &ptr_spec_mdct_mid[spec_start] : &ptr_spec_mdct_side[spec_start],
362             pstr_usac_data->complex_coef[chn] == 1 ? &pstr_usac_data->ptr_dmx_im[chn][spec_start]
363                                                    : NULL,
364             *pred_dir == 0 ? &ptr_spec_mdct_side[spec_start] : &ptr_spec_mdct_mid[spec_start],
365             &ptr_spec_mdct_res[spec_start]);
366       }
367     }
368   }
369 
370   /* Compute the prediction gain */
371   FLOAT32 pred_gain = 0.f, nrg_res = 0.f;
372   for (i = 0; i < pstr_usac_config->ccfl; i++) {
373     nrg_res += (FLOAT32)(ptr_spec_mdct_res[i] * ptr_spec_mdct_res[i]);
374   }
375   pred_gain = 10.f * log10f(ixheaace_div32((*pred_dir == 0 ? nrg_side : nrg_mid), nrg_res));
376       /* Prediction gain in dB */
377 
378   if (pred_gain > 20.f) /* Retain complex prediction */
379   {
380     if (*pred_dir == 1) {
381       for (i = 0; i < pstr_usac_config->ccfl; i++) {
382         ptr_spec_mdct_mid[i] = ptr_spec_mdct_side[i];
383         ptr_spec_mdct_side[i] = ptr_spec_mdct_res[i];
384       }
385     } else {
386       for (i = 0; i < pstr_usac_config->ccfl; i++) {
387         ptr_spec_mdct_side[i] = ptr_spec_mdct_res[i];
388       }
389     }
390   } else /* Use M/S */
391   {
392     *ms_mask_flag = 0;
393     /* Revert spectra to L and R */
394     for (i = 0; i < pstr_usac_config->ccfl; i++) {
395       ptr_spec_mdct_mid[i] = pstr_usac_data->left_chan_save[chn][i];
396       ptr_spec_mdct_side[i] = pstr_usac_data->right_chan_save[chn][i];
397     }
398   }
399 
400   return IA_NO_ERROR;
401 }
402 
iusace_cplx_pred_proc(ia_usac_data_struct * pstr_usac_data,ia_usac_encoder_config_struct * pstr_usac_config,WORD32 usac_independancy_flag,ia_sfb_params_struct * pstr_sfb_prms,WORD32 chn,ia_psy_mod_data_struct * pstr_psy_data,const WORD32 * ptr_sfb_offsets,FLOAT64 * ptr_scratch_cmpx_mdct_buf,FLOAT64 * ptr_ms_spec,FLOAT32 nrg_mid,FLOAT32 nrg_side)403 IA_ERRORCODE iusace_cplx_pred_proc(
404     ia_usac_data_struct *pstr_usac_data, ia_usac_encoder_config_struct *pstr_usac_config,
405     WORD32 usac_independancy_flag, ia_sfb_params_struct *pstr_sfb_prms, WORD32 chn,
406     ia_psy_mod_data_struct *pstr_psy_data, const WORD32 *ptr_sfb_offsets,
407     FLOAT64 *ptr_scratch_cmpx_mdct_buf, FLOAT64 *ptr_ms_spec, FLOAT32 nrg_mid, FLOAT32 nrg_side) {
408   IA_ERRORCODE err_code;
409   FLOAT32 *ptr_sfb_enegry_left = pstr_psy_data[chn].ptr_sfb_energy_long;
410   FLOAT32 *ptr_sfb_energy_right = pstr_psy_data[chn + 1].ptr_sfb_energy_long;
411   const FLOAT32 *ptr_sfb_energy_mid = pstr_psy_data[chn].ptr_sfb_energy_long_ms;
412   const FLOAT32 *ptr_sfb_energy_side = pstr_psy_data[chn + 1].ptr_sfb_energy_long_ms;
413   FLOAT32 *ptr_sfb_thr_left = pstr_psy_data[chn].ptr_sfb_thr_long;
414   FLOAT32 *ptr_sfb_thr_right = pstr_psy_data[chn + 1].ptr_sfb_thr_long;
415   FLOAT32 *ptr_sfb_spread_energy_left = pstr_psy_data[chn].ptr_sfb_spreaded_energy_long;
416   FLOAT32 *ptr_sfb_spread_energy_right = pstr_psy_data[chn + 1].ptr_sfb_spreaded_energy_long;
417   WORD32 sfb, sfb_offsets;
418   WORD32 *ptr_num_sfb = pstr_sfb_prms->num_sfb;
419   WORD32 *ptr_num_window_groups = pstr_sfb_prms->num_window_groups;
420   const WORD32 sfb_count = ptr_num_window_groups[chn] * ptr_num_sfb[chn];
421   const WORD32 sfb_per_group = ptr_num_sfb[chn];
422   WORD32 grp = 0, i, zero_flag;
423   const WORD32 sfb_per_pred_band = 2;
424   FLOAT32 min_thr_1, min_thr_2 = 0.0f;
425   FLOAT32 temp_1 = 0, temp_2 = 0;
426   ia_ms_info_struct *pstr_ms_info = &pstr_usac_data->str_ms_info[chn];
427 
428   FLOAT64 ipd;
429   /* Compute IPD between L and R channels */
430   ipd = iusace_compute_ipd(&pstr_usac_data->spectral_line_vector[chn][0],
431                            &pstr_usac_data->mdst_spectrum[chn][0],
432                            &pstr_usac_data->spectral_line_vector[chn + 1][0],
433                            &pstr_usac_data->mdst_spectrum[chn + 1][0], pstr_usac_config->ccfl);
434 
435   /* Decide value of complex_coef based on IPD */
436   if ((ipd > (PI / 2 - 5 * PI / 180) && ipd < (PI / 2 + 5 * PI / 180)) ||
437       (ipd > (3 * PI / 2 - 5 * PI / 180) && ipd < (3 * PI / 2 + 5 * PI / 180))) {
438     pstr_usac_data->complex_coef[chn] = 1;
439   } else {
440     pstr_usac_data->complex_coef[chn] = 0;
441   }
442 
443   /* Compute M and S spectra */
444   for (i = 0; i < pstr_usac_config->ccfl; i++) {
445     pstr_usac_data->spectral_line_vector[chn][i] = ptr_ms_spec[i];
446     pstr_usac_data->spectral_line_vector[chn + 1][i] = ptr_ms_spec[pstr_usac_config->ccfl + i];
447   }
448 
449   err_code = iusace_cplx_pred_main(
450       pstr_sfb_prms->num_sfb[chn], pstr_sfb_prms->num_window_groups[chn],
451       pstr_usac_data->spectral_line_vector[chn], pstr_usac_data->spectral_line_vector[chn + 1],
452       pstr_usac_data->pred_coef_re[chn], pstr_usac_data->pred_coef_im[chn],
453       &pstr_usac_data->pred_dir_idx[chn], pstr_usac_data, pstr_sfb_prms, usac_independancy_flag,
454       pstr_usac_config, ptr_scratch_cmpx_mdct_buf, pstr_usac_data->cplx_pred_used[chn], chn,
455       ptr_sfb_offsets, nrg_mid, nrg_side, &pstr_ms_info->ms_mask);
456   if (err_code != IA_NO_ERROR) {
457     return err_code;
458   }
459 
460   if (pstr_ms_info->ms_mask == 3) {
461     /* Compute thresholds required for quantization (similar to that in MS coding) */
462     for (sfb = 0; sfb < sfb_count; sfb += sfb_per_group, grp++) {
463       for (sfb_offsets = 0; sfb_offsets < sfb_per_group; sfb_offsets += sfb_per_pred_band) {
464         if (pstr_usac_data->cplx_pred_used[chn][grp][sfb_offsets] == 1) {
465           zero_flag = (ptr_sfb_offsets[sfb + sfb_offsets + 1] != pstr_usac_config->ccfl);
466           min_thr_1 =
467               MIN(ptr_sfb_thr_left[sfb + sfb_offsets], ptr_sfb_thr_right[sfb + sfb_offsets]);
468           if (zero_flag) {
469             min_thr_2 = MIN(ptr_sfb_thr_left[sfb + sfb_offsets + 1],
470                             ptr_sfb_thr_right[sfb + sfb_offsets + 1]);
471           }
472 
473           ptr_sfb_thr_left[sfb + sfb_offsets] = ptr_sfb_thr_right[sfb + sfb_offsets] = min_thr_1;
474           ptr_sfb_enegry_left[sfb + sfb_offsets] = ptr_sfb_energy_mid[sfb + sfb_offsets];
475           ptr_sfb_energy_right[sfb + sfb_offsets] = ptr_sfb_energy_side[sfb + sfb_offsets];
476           if (zero_flag) {
477             ptr_sfb_thr_left[sfb + sfb_offsets + 1] = ptr_sfb_thr_right[sfb + sfb_offsets + 1] =
478                 min_thr_2;
479             ptr_sfb_enegry_left[sfb + sfb_offsets + 1] =
480                 ptr_sfb_energy_mid[sfb + sfb_offsets + 1];
481             ptr_sfb_energy_right[sfb + sfb_offsets + 1] =
482                 ptr_sfb_energy_side[sfb + sfb_offsets + 1];
483           }
484           ptr_sfb_spread_energy_left[sfb + sfb_offsets] =
485               ptr_sfb_spread_energy_right[sfb + sfb_offsets] =
486                   MIN(ptr_sfb_spread_energy_left[sfb + sfb_offsets],
487                       ptr_sfb_spread_energy_right[sfb + sfb_offsets]) *
488                   0.5f;
489           if (zero_flag) {
490             ptr_sfb_spread_energy_left[sfb + sfb_offsets + 1] =
491                 ptr_sfb_spread_energy_right[sfb + sfb_offsets + 1] =
492                     MIN(ptr_sfb_spread_energy_left[sfb + sfb_offsets + 1],
493                         ptr_sfb_spread_energy_right[sfb + sfb_offsets + 1]) *
494                     0.5f;
495           }
496         }
497       }
498     }
499 
500     if (pstr_usac_data->pred_dir_idx[chn] == 1) {
501       grp = 0;
502 
503       for (sfb = 0; sfb < sfb_count; sfb += sfb_per_group, grp++) {
504         for (sfb_offsets = 0; sfb_offsets < sfb_per_group; sfb_offsets += sfb_per_pred_band) {
505           zero_flag = (ptr_sfb_offsets[sfb + sfb_offsets + 1] != pstr_usac_config->ccfl);
506 
507           if (pstr_usac_data->cplx_pred_used[chn][grp][sfb_offsets] == 1) {
508             temp_1 = ptr_sfb_enegry_left[sfb + sfb_offsets];
509             ptr_sfb_enegry_left[sfb + sfb_offsets] = ptr_sfb_energy_right[sfb + sfb_offsets];
510             ptr_sfb_energy_right[sfb + sfb_offsets] = temp_1;
511             if (zero_flag) {
512               temp_2 = ptr_sfb_enegry_left[sfb + sfb_offsets + 1];
513               ptr_sfb_enegry_left[sfb + sfb_offsets + 1] =
514                   ptr_sfb_energy_right[sfb + sfb_offsets + 1];
515               ptr_sfb_energy_right[sfb + sfb_offsets + 1] = temp_2;
516             }
517           }
518         }
519       }
520     }
521   }
522   return IA_NO_ERROR;
523 }
524