/src/libxaac/encoder/ixheaace_sbr_tran_det.c

Source
/******************************************************************************
 *                                                                            *
 * Copyright (C) 2023 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 *****************************************************************************
 * Originally developed and contributed by Ittiam Systems Pvt. Ltd, Bangalore
 */

#include <math.h>
#include <string.h>
#include "ixheaac_type_def.h"
#include "ixheaac_constants.h"
#include "ixheaace_aac_constants.h"
#include "ixheaac_error_standards.h"
#include "ixheaace_error_codes.h"
#include "ixheaac_basic_ops32.h"
#include "ixheaac_basic_ops16.h"
#include "ixheaac_basic_ops40.h"
#include "ixheaac_basic_ops.h"

#include "ixheaace_common_rom.h"
#include "ixheaace_sbr_header.h"
#include "ixheaace_sbr_def.h"
#include "ixheaace_resampler.h"
#include "ixheaace_sbr_rom.h"
#include "ixheaace_sbr_tran_det.h"
#include "ixheaace_sbr_main.h"
#include "ixheaace_sbr_frame_info_gen.h"

static IA_ERRORCODE ixheaace_spectral_change(FLOAT32 *ptr_energies[16], FLOAT32 total_energy,
                                             WORD32 num_sfb, WORD32 start, WORD32 border,
                                             WORD32 stop, WORD32 is_ld_sbr, FLOAT32 *ptr_delta) {
  WORD32 i, j;
  WORD32 len1 = border - start;
  WORD32 len2 = stop - border;
  FLOAT32 energy_1[MAXIMUM_FREQ_COEFFS] = {0};
  FLOAT32 energy_2[MAXIMUM_FREQ_COEFFS] = {0};
  FLOAT32 len_ratio = (FLOAT32)len1 / (FLOAT32)(len2);
  FLOAT32 delta, delta_sum = 0.0f;
  FLOAT32 pos_wt = (0.5f - (FLOAT32)len1 / (FLOAT32)(len1 + len2));
  pos_wt = 1.0f - 4.0f * pos_wt * pos_wt;

  if (total_energy < SBR_EPS) {
    *ptr_delta = 0.0f;
    return IA_NO_ERROR;
  }

  if (!is_ld_sbr) {
    for (j = 0; j < num_sfb; j++) {
      energy_1[j] = 1.0e6f * len1;
      energy_2[j] = 1.0e6f * len2;
    }
  }

  for (j = 0; j < num_sfb; j++) {
    for (i = start; i < border; i++) {
      energy_1[j] += ptr_energies[i][j];
    }

    for (i = border; i < stop; i++) {
      energy_2[j] += ptr_energies[i][j];
    }
    if (energy_1[j] <= EPS) {
      energy_1[j] = (FLOAT32)len1;
    }
    if (energy_2[j] <= EPS) {
      energy_2[j] = (FLOAT32)len2;
    }
    delta = (FLOAT32)fabs(log((energy_2[j] / energy_1[j]) * len_ratio));
    delta_sum += (FLOAT32)(sqrt((energy_1[j] + energy_2[j]) / total_energy) * delta);
  }

  *ptr_delta = delta_sum * pos_wt;
  return IA_NO_ERROR;
}

FLOAT32 ixheaace_add_lowband_energies(FLOAT32 **ptr_energies, UWORD8 *ptr_freq_band_tab,
                                      WORD32 time_slots, WORD32 is_ld_sbr, WORD32 time_step) {
  WORD32 band, ts;
  FLOAT32 energy = 1.0f;
  WORD32 tran_offset = 0;
  if (is_ld_sbr) {
    tran_offset = 7;
    energy = 0.0f;
  } else {
    tran_offset = time_slots / 2;
  }

  for (ts = tran_offset; ts < time_slots + tran_offset; ts++) {
    for (band = 0; band < ptr_freq_band_tab[0]; band++) {
      energy += ptr_energies[ts][band];
    }
  }

  energy *= time_step;

  return energy;
}

static FLOAT32 ixheaace_add_highband_energies(FLOAT32 **ptr_energies, FLOAT32 *ptr_energies_m[16],
                                              UWORD8 *ptr_freq_band_tab, WORD32 num_sfb,
                                              WORD32 time_slots, WORD32 time_step,
                                              WORD32 is_ld_sbr) {
  WORD32 band, ts, sfb, low_band, high_band;
  FLOAT32 energy = 1.0f, tmp;
  if (is_ld_sbr) {
    energy = 0.0f;
  }
  for (ts = 0; ts < time_slots; ts++) {
    for (sfb = 0; sfb < num_sfb; sfb++) {
      tmp = 0;
      low_band = ptr_freq_band_tab[sfb];
      high_band = ptr_freq_band_tab[sfb + 1];
      band = low_band;
      while (band < high_band) {
        tmp += (ptr_energies[ts][band] * time_step);
        band++;
      }
      ptr_energies_m[ts][sfb] = tmp;
      if (is_ld_sbr || time_step == 4) {
        energy += tmp;
      } else {
        energy += ptr_energies[ts][sfb];
      }
    }
  }
  return energy;
}

IA_ERRORCODE
ixheaace_frame_splitter(FLOAT32 **ptr_energies,
                        ixheaace_pstr_sbr_trans_detector pstr_sbr_trans_detector,
                        UWORD8 *ptr_freq_band_tab, WORD32 num_scf, WORD32 time_step,
                        WORD32 no_cols, WORD32 *ptr_tran_vector,
                        FLOAT32 *ptr_frame_splitter_scratch, WORD32 is_ld_sbr) {
  WORD32 border, i;
  WORD32 num_sbr_slots = no_cols / time_step;
  FLOAT32 *ptr_energies_m[16] = {0};
  FLOAT32 low_band_energy, high_band_energy, total_energy;
  FLOAT32 delta = 0.0f;
  IA_ERRORCODE err_code = IA_NO_ERROR;

  if ((num_sbr_slots <= 0) || (num_sbr_slots * time_step != no_cols)) {
    return IA_EXHEAACE_EXE_FATAL_SBR_INVALID_TIME_SLOTS;
  }

  memset(ptr_frame_splitter_scratch, 0,
         sizeof(ptr_energies_m[0][0]) * MAXIMUM_FREQ_COEFFS * num_sbr_slots);

  for (i = 0; i < num_sbr_slots; i++) {
    ptr_energies_m[i] = ptr_frame_splitter_scratch;
    ptr_frame_splitter_scratch += MAXIMUM_FREQ_COEFFS;
  }

  low_band_energy = ixheaace_add_lowband_energies(ptr_energies, ptr_freq_band_tab, num_sbr_slots,
                                                  is_ld_sbr, time_step);

  high_band_energy =
      ixheaace_add_highband_energies(ptr_energies, ptr_energies_m, ptr_freq_band_tab, num_scf,
                                     num_sbr_slots, time_step, is_ld_sbr);
  border = (num_sbr_slots + 1) >> 1;

  total_energy = 0.5f * (low_band_energy + pstr_sbr_trans_detector->prev_low_band_energy);
  total_energy += high_band_energy;
  if ((total_energy > IXHEAACE_SBR_ENERGY_THRESHOLD) || (!is_ld_sbr)) {
    err_code = ixheaace_spectral_change(ptr_energies_m, total_energy, num_scf, 0, border,
                                        num_sbr_slots, is_ld_sbr, &delta);
    if (err_code) {
      return err_code;
    }
  } else if (is_ld_sbr) {
    delta = 0;
  }

  if (delta > pstr_sbr_trans_detector->split_thr) {
    ptr_tran_vector[0] = 1;
  } else {
    ptr_tran_vector[0] = 0;
  }
  pstr_sbr_trans_detector->prev_low_band_energy = low_band_energy;
  return err_code;
}

VOID ixheaace_create_sbr_transient_detector(
    ixheaace_pstr_sbr_trans_detector pstr_sbr_trans_detector, WORD32 sample_freq,
    WORD32 total_bitrate, WORD32 codec_bitrate, WORD32 tran_thr, WORD32 mode, WORD32 tran_fc,
    WORD32 frame_flag_480, WORD32 is_ld_sbr, WORD32 sbr_ratio_idx,
    ixheaace_sbr_codec_type sbr_codec, WORD32 start_band) {
  WORD32 no_cols = 32, buffer_length = 96;
  FLOAT32 br_fac;
  FLOAT32 frm_dur = 2048.0f / (FLOAT32)sample_freq;
  FLOAT32 split_thr_fac = frm_dur - 0.01f;
  if ((sbr_codec == USAC_SBR) && (sbr_ratio_idx == USAC_SBR_RATIO_INDEX_4_1)) {
    frm_dur = frm_dur * 2;
    split_thr_fac = frm_dur - 0.01f;
    no_cols = 64;
  }
  if ((1 == is_ld_sbr) && (1 == frame_flag_480)) {
    no_cols = 30;
    buffer_length = 90;
  }

  memset(pstr_sbr_trans_detector, 0, sizeof(ixheaace_str_sbr_trans_detector));

  br_fac = codec_bitrate ? (FLOAT32)total_bitrate / (FLOAT32)codec_bitrate : 1.0f;

  split_thr_fac = MAX(split_thr_fac, 0.0001f);
  split_thr_fac = 0.000075f / (split_thr_fac * split_thr_fac);

  pstr_sbr_trans_detector->split_thr = split_thr_fac * br_fac;

  if (is_ld_sbr) {
    WORD32 i;
    FLOAT32 ratio = ((sample_freq / 2) / IXHEAACE_QMF_CHANNELS) * 0.00075275f;

    FLOAT32 tmp = 1024.0f / sample_freq;
    tmp -= 0.01f;
    tmp = MAX(tmp, 0.001f);

    if (1 == frame_flag_480) {
      no_cols = 30;
      buffer_length = 90;
    }
    pstr_sbr_trans_detector->split_thr = (br_fac * 0.000075f) / (tmp * tmp) / 2.0f;
    pstr_sbr_trans_detector->look_ahead = 2;
    pstr_sbr_trans_detector->time_slots = no_cols / 2;
    pstr_sbr_trans_detector->buffer_size =
        pstr_sbr_trans_detector->look_ahead + pstr_sbr_trans_detector->time_slots;
    pstr_sbr_trans_detector->stop_band =
        (WORD32)fmin(13500 / ((sample_freq >> 1) / IXHEAACE_QMF_CHANNELS), IXHEAACE_QMF_CHANNELS);
    pstr_sbr_trans_detector->start_band =
        (WORD32)fmin(start_band, pstr_sbr_trans_detector->stop_band - 4);

    memset(pstr_sbr_trans_detector->energy, 0,
           pstr_sbr_trans_detector->buffer_size * sizeof(pstr_sbr_trans_detector->energy[0]));
    memset(pstr_sbr_trans_detector->sbr_transients, 0,
           pstr_sbr_trans_detector->buffer_size *
               sizeof(pstr_sbr_trans_detector->sbr_transients[0]));
    memset(
        pstr_sbr_trans_detector->delta_energy, 0,
        pstr_sbr_trans_detector->buffer_size * sizeof(pstr_sbr_trans_detector->delta_energy[0]));

    for (i = 0; i < 64; i++) {
      pstr_sbr_trans_detector->coeff[i] = (FLOAT32)pow(2.0, ratio * (i + 1));
    }
  }
  pstr_sbr_trans_detector->no_cols = no_cols;
  pstr_sbr_trans_detector->tran_fc = tran_fc;

  pstr_sbr_trans_detector->buffer_length = buffer_length;

  pstr_sbr_trans_detector->no_rows = 64;
  pstr_sbr_trans_detector->mode = mode;

  pstr_sbr_trans_detector->prev_low_band_energy = 0;
  pstr_sbr_trans_detector->tran_thr = (FLOAT32)tran_thr;

  pstr_sbr_trans_detector->ptr_thresholds = &(pstr_sbr_trans_detector->sbr_thresholds[0]);

  memset(pstr_sbr_trans_detector->ptr_thresholds, 0,
         sizeof(pstr_sbr_trans_detector->ptr_thresholds[0]) * IXHEAACE_QMF_CHANNELS);

  pstr_sbr_trans_detector->ptr_transients = &(pstr_sbr_trans_detector->sbr_transients[0]);
  memset(pstr_sbr_trans_detector->ptr_transients, 0,
         sizeof(pstr_sbr_trans_detector->ptr_transients[0]) *
             pstr_sbr_trans_detector->buffer_length);
}

Coverage Report

Created: 2026-03-31 06:52

Line	Count	Source
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 "ixheaac_type_def.h"
24		#include "ixheaac_constants.h"
25		#include "ixheaace_aac_constants.h"
26		#include "ixheaac_error_standards.h"
27		#include "ixheaace_error_codes.h"
28		#include "ixheaac_basic_ops32.h"
29		#include "ixheaac_basic_ops16.h"
30		#include "ixheaac_basic_ops40.h"
31		#include "ixheaac_basic_ops.h"
32
33		#include "ixheaace_common_rom.h"
34		#include "ixheaace_sbr_header.h"
35		#include "ixheaace_sbr_def.h"
36		#include "ixheaace_resampler.h"
37		#include "ixheaace_sbr_rom.h"
38		#include "ixheaace_sbr_tran_det.h"
39		#include "ixheaace_sbr_main.h"
40		#include "ixheaace_sbr_frame_info_gen.h"
41
42		static IA_ERRORCODE ixheaace_spectral_change(FLOAT32 *ptr_energies[16], FLOAT32 total_energy,
43		WORD32 num_sfb, WORD32 start, WORD32 border,
44	390k	WORD32 stop, WORD32 is_ld_sbr, FLOAT32 *ptr_delta) {
45	390k	WORD32 i, j;
46	390k	WORD32 len1 = border - start;
47	390k	WORD32 len2 = stop - border;
48	390k	FLOAT32 energy_1[MAXIMUM_FREQ_COEFFS] = {0};
49	390k	FLOAT32 energy_2[MAXIMUM_FREQ_COEFFS] = {0};
50	390k	FLOAT32 len_ratio = (FLOAT32)len1 / (FLOAT32)(len2);
51	390k	FLOAT32 delta, delta_sum = 0.0f;
52	390k	FLOAT32 pos_wt = (0.5f - (FLOAT32)len1 / (FLOAT32)(len1 + len2));
53	390k	pos_wt = 1.0f - 4.0f * pos_wt * pos_wt;
54
55	390k	if (total_energy < SBR_EPS) {
56	0	*ptr_delta = 0.0f;
57	0	return IA_NO_ERROR;
58	0	}
59
60	390k	if (!is_ld_sbr) {
61	4.61M	for (j = 0; j < num_sfb; j++) {
62	4.27M	energy_1[j] = 1.0e6f * len1;
63	4.27M	energy_2[j] = 1.0e6f * len2;
64	4.27M	}
65	339k	}
66
67	5.37M	for (j = 0; j < num_sfb; j++) {
68	44.8M	for (i = start; i < border; i++) {
69	39.8M	energy_1[j] += ptr_energies[i][j];
70	39.8M	}
71
72	44.5M	for (i = border; i < stop; i++) {
73	39.5M	energy_2[j] += ptr_energies[i][j];
74	39.5M	}
75	4.98M	if (energy_1[j] <= EPS) {
76	2.73k	energy_1[j] = (FLOAT32)len1;
77	2.73k	}
78	4.98M	if (energy_2[j] <= EPS) {
79	24.6k	energy_2[j] = (FLOAT32)len2;
80	24.6k	}
81	4.98M	delta = (FLOAT32)fabs(log((energy_2[j] / energy_1[j]) * len_ratio));
82	4.98M	delta_sum += (FLOAT32)(sqrt((energy_1[j] + energy_2[j]) / total_energy) * delta);
83	4.98M	}
84
85	390k	ptr_delta = delta_sum pos_wt;
86	390k	return IA_NO_ERROR;
87	390k	}
88
89		FLOAT32 ixheaace_add_lowband_energies(FLOAT32 *ptr_energies, UWORD8 ptr_freq_band_tab,
90	419k	WORD32 time_slots, WORD32 is_ld_sbr, WORD32 time_step) {
91	419k	WORD32 band, ts;
92	419k	FLOAT32 energy = 1.0f;
93	419k	WORD32 tran_offset = 0;
94	419k	if (is_ld_sbr) {
95	80.6k	tran_offset = 7;
96	80.6k	energy = 0.0f;
97	339k	} else {
98	339k	tran_offset = time_slots / 2;
99	339k	}
100
101	7.09M	for (ts = tran_offset; ts < time_slots + tran_offset; ts++) {
102	148M	for (band = 0; band < ptr_freq_band_tab[0]; band++) {
103	141M	energy += ptr_energies[ts][band];
104	141M	}
105	6.67M	}
106
107	419k	energy *= time_step;
108
109	419k	return energy;
110	419k	}
111
112		static FLOAT32 ixheaace_add_highband_energies(FLOAT32 *ptr_energies, FLOAT32 ptr_energies_m[16],
113		UWORD8 *ptr_freq_band_tab, WORD32 num_sfb,
114		WORD32 time_slots, WORD32 time_step,
115	419k	WORD32 is_ld_sbr) {
116	419k	WORD32 band, ts, sfb, low_band, high_band;
117	419k	FLOAT32 energy = 1.0f, tmp;
118	419k	if (is_ld_sbr) {
119	80.6k	energy = 0.0f;
120	80.6k	}
121	7.09M	for (ts = 0; ts < time_slots; ts++) {
122	92.2M	for (sfb = 0; sfb < num_sfb; sfb++) {
123	85.6M	tmp = 0;
124	85.6M	low_band = ptr_freq_band_tab[sfb];
125	85.6M	high_band = ptr_freq_band_tab[sfb + 1];
126	85.6M	band = low_band;
127	282M	while (band < high_band) {
128	196M	tmp += (ptr_energies[ts][band] * time_step);
129	196M	band++;
130	196M	}
131	85.6M	ptr_energies_m[ts][sfb] = tmp;
132	85.6M	if (is_ld_sbr \|\| time_step == 4) {
133	31.3M	energy += tmp;
134	54.2M	} else {
135	54.2M	energy += ptr_energies[ts][sfb];
136	54.2M	}
137	85.6M	}
138	6.67M	}
139	419k	return energy;
140	419k	}
141
142		IA_ERRORCODE
143		ixheaace_frame_splitter(FLOAT32 **ptr_energies,
144		ixheaace_pstr_sbr_trans_detector pstr_sbr_trans_detector,
145		UWORD8 *ptr_freq_band_tab, WORD32 num_scf, WORD32 time_step,
146		WORD32 no_cols, WORD32 *ptr_tran_vector,
147	419k	FLOAT32 *ptr_frame_splitter_scratch, WORD32 is_ld_sbr) {
148	419k	WORD32 border, i;
149	419k	WORD32 num_sbr_slots = no_cols / time_step;
150	419k	FLOAT32 *ptr_energies_m[16] = {0};
151	419k	FLOAT32 low_band_energy, high_band_energy, total_energy;
152	419k	FLOAT32 delta = 0.0f;
153	419k	IA_ERRORCODE err_code = IA_NO_ERROR;
154
155	419k	if ((num_sbr_slots <= 0) \|\| (num_sbr_slots * time_step != no_cols)) {
156	0	return IA_EXHEAACE_EXE_FATAL_SBR_INVALID_TIME_SLOTS;
157	0	}
158
159	419k	memset(ptr_frame_splitter_scratch, 0,
160	419k	sizeof(ptr_energies_m[0][0]) * MAXIMUM_FREQ_COEFFS * num_sbr_slots);
161
162	7.09M	for (i = 0; i < num_sbr_slots; i++) {
163	6.67M	ptr_energies_m[i] = ptr_frame_splitter_scratch;
164	6.67M	ptr_frame_splitter_scratch += MAXIMUM_FREQ_COEFFS;
165	6.67M	}
166
167	419k	low_band_energy = ixheaace_add_lowband_energies(ptr_energies, ptr_freq_band_tab, num_sbr_slots,
168	419k	is_ld_sbr, time_step);
169
170	419k	high_band_energy =
171	419k	ixheaace_add_highband_energies(ptr_energies, ptr_energies_m, ptr_freq_band_tab, num_scf,
172	419k	num_sbr_slots, time_step, is_ld_sbr);
173	419k	border = (num_sbr_slots + 1) >> 1;
174
175	419k	total_energy = 0.5f * (low_band_energy + pstr_sbr_trans_detector->prev_low_band_energy);
176	419k	total_energy += high_band_energy;
177	419k	if ((total_energy > IXHEAACE_SBR_ENERGY_THRESHOLD) \|\| (!is_ld_sbr)) {
178	390k	err_code = ixheaace_spectral_change(ptr_energies_m, total_energy, num_scf, 0, border,
179	390k	num_sbr_slots, is_ld_sbr, &delta);
180	390k	if (err_code) {
181	0	return err_code;
182	0	}
183	390k	} else if (is_ld_sbr) {
184	29.4k	delta = 0;
185	29.4k	}
186
187	419k	if (delta > pstr_sbr_trans_detector->split_thr) {
188	38.8k	ptr_tran_vector[0] = 1;
189	380k	} else {
190	380k	ptr_tran_vector[0] = 0;
191	380k	}
192	419k	pstr_sbr_trans_detector->prev_low_band_energy = low_band_energy;
193	419k	return err_code;
194	419k	}
195
196		VOID ixheaace_create_sbr_transient_detector(
197		ixheaace_pstr_sbr_trans_detector pstr_sbr_trans_detector, WORD32 sample_freq,
198		WORD32 total_bitrate, WORD32 codec_bitrate, WORD32 tran_thr, WORD32 mode, WORD32 tran_fc,
199		WORD32 frame_flag_480, WORD32 is_ld_sbr, WORD32 sbr_ratio_idx,
200	8.86k	ixheaace_sbr_codec_type sbr_codec, WORD32 start_band) {
201	8.86k	WORD32 no_cols = 32, buffer_length = 96;
202	8.86k	FLOAT32 br_fac;
203	8.86k	FLOAT32 frm_dur = 2048.0f / (FLOAT32)sample_freq;
204	8.86k	FLOAT32 split_thr_fac = frm_dur - 0.01f;
205	8.86k	if ((sbr_codec == USAC_SBR) && (sbr_ratio_idx == USAC_SBR_RATIO_INDEX_4_1)) {
206	805	frm_dur = frm_dur * 2;
207	805	split_thr_fac = frm_dur - 0.01f;
208	805	no_cols = 64;
209	805	}
210	8.86k	if ((1 == is_ld_sbr) && (1 == frame_flag_480)) {
211	884	no_cols = 30;
212	884	buffer_length = 90;
213	884	}
214
215	8.86k	memset(pstr_sbr_trans_detector, 0, sizeof(ixheaace_str_sbr_trans_detector));
216
217	8.86k	br_fac = codec_bitrate ? (FLOAT32)total_bitrate / (FLOAT32)codec_bitrate : 1.0f;
218
219	8.86k	split_thr_fac = MAX(split_thr_fac, 0.0001f);
220	8.86k	split_thr_fac = 0.000075f / (split_thr_fac * split_thr_fac);
221
222	8.86k	pstr_sbr_trans_detector->split_thr = split_thr_fac * br_fac;
223
224	8.86k	if (is_ld_sbr) {
225	1.87k	WORD32 i;
226	1.87k	FLOAT32 ratio = ((sample_freq / 2) / IXHEAACE_QMF_CHANNELS) * 0.00075275f;
227
228	1.87k	FLOAT32 tmp = 1024.0f / sample_freq;
229	1.87k	tmp -= 0.01f;
230	1.87k	tmp = MAX(tmp, 0.001f);
231
232	1.87k	if (1 == frame_flag_480) {
233	884	no_cols = 30;
234	884	buffer_length = 90;
235	884	}
236	1.87k	pstr_sbr_trans_detector->split_thr = (br_fac * 0.000075f) / (tmp * tmp) / 2.0f;
237	1.87k	pstr_sbr_trans_detector->look_ahead = 2;
238	1.87k	pstr_sbr_trans_detector->time_slots = no_cols / 2;
239	1.87k	pstr_sbr_trans_detector->buffer_size =
240	1.87k	pstr_sbr_trans_detector->look_ahead + pstr_sbr_trans_detector->time_slots;
241	1.87k	pstr_sbr_trans_detector->stop_band =
242	1.87k	(WORD32)fmin(13500 / ((sample_freq >> 1) / IXHEAACE_QMF_CHANNELS), IXHEAACE_QMF_CHANNELS);
243	1.87k	pstr_sbr_trans_detector->start_band =
244	1.87k	(WORD32)fmin(start_band, pstr_sbr_trans_detector->stop_band - 4);
245
246	1.87k	memset(pstr_sbr_trans_detector->energy, 0,
247	1.87k	pstr_sbr_trans_detector->buffer_size * sizeof(pstr_sbr_trans_detector->energy[0]));
248	1.87k	memset(pstr_sbr_trans_detector->sbr_transients, 0,
249	1.87k	pstr_sbr_trans_detector->buffer_size *
250	1.87k	sizeof(pstr_sbr_trans_detector->sbr_transients[0]));
251	1.87k	memset(
252	1.87k	pstr_sbr_trans_detector->delta_energy, 0,
253	1.87k	pstr_sbr_trans_detector->buffer_size * sizeof(pstr_sbr_trans_detector->delta_energy[0]));
254
255	122k	for (i = 0; i < 64; i++) {
256	120k	pstr_sbr_trans_detector->coeff[i] = (FLOAT32)pow(2.0, ratio * (i + 1));
257	120k	}
258	1.87k	}
259	8.86k	pstr_sbr_trans_detector->no_cols = no_cols;
260	8.86k	pstr_sbr_trans_detector->tran_fc = tran_fc;
261
262	8.86k	pstr_sbr_trans_detector->buffer_length = buffer_length;
263
264	8.86k	pstr_sbr_trans_detector->no_rows = 64;
265	8.86k	pstr_sbr_trans_detector->mode = mode;
266
267	8.86k	pstr_sbr_trans_detector->prev_low_band_energy = 0;
268	8.86k	pstr_sbr_trans_detector->tran_thr = (FLOAT32)tran_thr;
269
270	8.86k	pstr_sbr_trans_detector->ptr_thresholds = &(pstr_sbr_trans_detector->sbr_thresholds[0]);
271
272	8.86k	memset(pstr_sbr_trans_detector->ptr_thresholds, 0,
273	8.86k	sizeof(pstr_sbr_trans_detector->ptr_thresholds[0]) * IXHEAACE_QMF_CHANNELS);
274
275	8.86k	pstr_sbr_trans_detector->ptr_transients = &(pstr_sbr_trans_detector->sbr_transients[0]);
276	8.86k	memset(pstr_sbr_trans_detector->ptr_transients, 0,
277	8.86k	sizeof(pstr_sbr_trans_detector->ptr_transients[0]) *
278	8.86k	pstr_sbr_trans_detector->buffer_length);
279	8.86k	}