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path: root/audio_codec/libfaad/sbr_tf_grid.c (plain)
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1/*
2** FAAD2 - Freeware Advanced Audio (AAC) Decoder including SBR decoding
3** Copyright (C) 2003-2005 M. Bakker, Nero AG, http://www.nero.com
4**
5** This program is free software; you can redistribute it and/or modify
6** it under the terms of the GNU General Public License as published by
7** the Free Software Foundation; either version 2 of the License, or
8** (at your option) any later version.
9**
10** This program is distributed in the hope that it will be useful,
11** but WITHOUT ANY WARRANTY; without even the implied warranty of
12** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13** GNU General Public License for more details.
14**
15** You should have received a copy of the GNU General Public License
16** along with this program; if not, write to the Free Software
17** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
18**
19** Any non-GPL usage of this software or parts of this software is strictly
20** forbidden.
21**
22** The "appropriate copyright message" mentioned in section 2c of the GPLv2
23** must read: "Code from FAAD2 is copyright (c) Nero AG, www.nero.com"
24**
25** Commercial non-GPL licensing of this software is possible.
26** For more info contact Nero AG through Mpeg4AAClicense@nero.com.
27**
28** $Id: sbr_tf_grid.c,v 1.20 2008/09/19 22:50:20 menno Exp $
29**/
30
31/* Time/Frequency grid */
32#include <stdlib.h>
33#include "common.h"
34#include "structs.h"
35
36#ifdef SBR_DEC
37
38
39#include "sbr_syntax.h"
40#include "sbr_tf_grid.h"
41
42
43/* static function declarations */
44#if 0
45static int16_t rel_bord_lead(sbr_info *sbr, uint8_t ch, uint8_t l);
46static int16_t rel_bord_trail(sbr_info *sbr, uint8_t ch, uint8_t l);
47#endif
48static uint8_t middleBorder(sbr_info *sbr, uint8_t ch);
49
50
51/* function constructs new time border vector */
52/* first build into temp vector to be able to use previous vector on error */
53uint8_t envelope_time_border_vector(sbr_info *sbr, uint8_t ch)
54{
55 uint8_t l, border, temp;
56 uint8_t t_E_temp[6] = {0};
57
58 t_E_temp[0] = sbr->rate * sbr->abs_bord_lead[ch];
59 t_E_temp[sbr->L_E[ch]] = sbr->rate * sbr->abs_bord_trail[ch];
60
61 switch (sbr->bs_frame_class[ch]) {
62 case FIXFIX:
63 switch (sbr->L_E[ch]) {
64 case 4:
65 temp = (sbr->numTimeSlots / 4);
66 t_E_temp[3] = sbr->rate * 3 * temp;
67 t_E_temp[2] = sbr->rate * 2 * temp;
68 t_E_temp[1] = sbr->rate * temp;
69 break;
70 case 2:
71 t_E_temp[1] = sbr->rate * (sbr->numTimeSlots / 2);
72 break;
73 default:
74 break;
75 }
76 break;
77
78 case FIXVAR:
79 if (sbr->L_E[ch] > 1) {
80 int8_t i = sbr->L_E[ch];
81 border = sbr->abs_bord_trail[ch];
82
83 for (l = 0; l < (sbr->L_E[ch] - 1); l++) {
84 if (border < sbr->bs_rel_bord[ch][l]) {
85 return 1;
86 }
87
88 border -= sbr->bs_rel_bord[ch][l];
89 t_E_temp[--i] = sbr->rate * border;
90 }
91 }
92 break;
93
94 case VARFIX:
95 if (sbr->L_E[ch] > 1) {
96 int8_t i = 1;
97 border = sbr->abs_bord_lead[ch];
98
99 for (l = 0; l < (sbr->L_E[ch] - 1); l++) {
100 border += sbr->bs_rel_bord[ch][l];
101
102 if (sbr->rate * border + sbr->tHFAdj > sbr->numTimeSlotsRate + sbr->tHFGen) {
103 return 1;
104 }
105
106 t_E_temp[i++] = sbr->rate * border;
107 }
108 }
109 break;
110
111 case VARVAR:
112 if (sbr->bs_num_rel_0[ch]) {
113 int8_t i = 1;
114 border = sbr->abs_bord_lead[ch];
115
116 for (l = 0; l < sbr->bs_num_rel_0[ch]; l++) {
117 border += sbr->bs_rel_bord_0[ch][l];
118
119 if (sbr->rate * border + sbr->tHFAdj > sbr->numTimeSlotsRate + sbr->tHFGen) {
120 return 1;
121 }
122
123 t_E_temp[i++] = sbr->rate * border;
124 }
125 }
126
127 if (sbr->bs_num_rel_1[ch]) {
128 int8_t i = sbr->L_E[ch];
129 border = sbr->abs_bord_trail[ch];
130
131 for (l = 0; l < sbr->bs_num_rel_1[ch]; l++) {
132 if (border < sbr->bs_rel_bord_1[ch][l]) {
133 return 1;
134 }
135
136 border -= sbr->bs_rel_bord_1[ch][l];
137 t_E_temp[--i] = sbr->rate * border;
138 }
139 }
140 break;
141 }
142
143 /* no error occured, we can safely use this t_E vector */
144 for (l = 0; l < 6; l++) {
145 sbr->t_E[ch][l] = t_E_temp[l];
146 }
147
148 return 0;
149}
150
151void noise_floor_time_border_vector(sbr_info *sbr, uint8_t ch)
152{
153 sbr->t_Q[ch][0] = sbr->t_E[ch][0];
154
155 if (sbr->L_E[ch] == 1) {
156 sbr->t_Q[ch][1] = sbr->t_E[ch][1];
157 sbr->t_Q[ch][2] = 0;
158 } else {
159 uint8_t index = middleBorder(sbr, ch);
160 sbr->t_Q[ch][1] = sbr->t_E[ch][index];
161 sbr->t_Q[ch][2] = sbr->t_E[ch][sbr->L_E[ch]];
162 }
163}
164
165#if 0
166static int16_t rel_bord_lead(sbr_info *sbr, uint8_t ch, uint8_t l)
167{
168 uint8_t i;
169 int16_t acc = 0;
170
171 switch (sbr->bs_frame_class[ch]) {
172 case FIXFIX:
173 return sbr->numTimeSlots / sbr->L_E[ch];
174 case FIXVAR:
175 return 0;
176 case VARFIX:
177 for (i = 0; i < l; i++) {
178 acc += sbr->bs_rel_bord[ch][i];
179 }
180 return acc;
181 case VARVAR:
182 for (i = 0; i < l; i++) {
183 acc += sbr->bs_rel_bord_0[ch][i];
184 }
185 return acc;
186 }
187
188 return 0;
189}
190
191static int16_t rel_bord_trail(sbr_info *sbr, uint8_t ch, uint8_t l)
192{
193 uint8_t i;
194 int16_t acc = 0;
195
196 switch (sbr->bs_frame_class[ch]) {
197 case FIXFIX:
198 case VARFIX:
199 return 0;
200 case FIXVAR:
201 for (i = 0; i < l; i++) {
202 acc += sbr->bs_rel_bord[ch][i];
203 }
204 return acc;
205 case VARVAR:
206 for (i = 0; i < l; i++) {
207 acc += sbr->bs_rel_bord_1[ch][i];
208 }
209 return acc;
210 }
211
212 return 0;
213}
214#endif
215
216static uint8_t middleBorder(sbr_info *sbr, uint8_t ch)
217{
218 int8_t retval = 0;
219
220 switch (sbr->bs_frame_class[ch]) {
221 case FIXFIX:
222 retval = sbr->L_E[ch] / 2;
223 break;
224 case VARFIX:
225 if (sbr->bs_pointer[ch] == 0) {
226 retval = 1;
227 } else if (sbr->bs_pointer[ch] == 1) {
228 retval = sbr->L_E[ch] - 1;
229 } else {
230 retval = sbr->bs_pointer[ch] - 1;
231 }
232 break;
233 case FIXVAR:
234 case VARVAR:
235 if (sbr->bs_pointer[ch] > 1) {
236 retval = sbr->L_E[ch] + 1 - sbr->bs_pointer[ch];
237 } else {
238 retval = sbr->L_E[ch] - 1;
239 }
240 break;
241 }
242
243 return (retval > 0) ? retval : 0;
244}
245
246
247#endif
248
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