ref: 588f58881659672f919dd91027e408f12ad3a05a
dir: /libfaad/sbr_tf_grid.c/
/* ** FAAD2 - Freeware Advanced Audio (AAC) Decoder including SBR decoding ** Copyright (C) 2003-2005 M. Bakker, Nero AG, http://www.nero.com ** ** This program is free software; you can redistribute it and/or modify ** it under the terms of the GNU General Public License as published by ** the Free Software Foundation; either version 2 of the License, or ** (at your option) any later version. ** ** This program is distributed in the hope that it will be useful, ** but WITHOUT ANY WARRANTY; without even the implied warranty of ** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the ** GNU General Public License for more details. ** ** You should have received a copy of the GNU General Public License ** along with this program; if not, write to the Free Software ** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. ** ** Any non-GPL usage of this software or parts of this software is strictly ** forbidden. ** ** Software using this code must display the following message visibly in or ** on each copy of the software: ** "FAAD2 AAC/HE-AAC/HE-AACv2/DRM decoder (c) Nero AG, www.nero.com" ** in, for example, the about-box or help/startup screen. ** ** Commercial non-GPL licensing of this software is possible. ** For more info contact Nero AG through [email protected]. ** ** $Id: sbr_tf_grid.c,v 1.17 2006/05/07 18:09:02 menno Exp $ **/ /* Time/Frequency grid */ #include "common.h" #include "structs.h" #ifdef SBR_DEC #include <stdlib.h> #include "sbr_syntax.h" #include "sbr_tf_grid.h" /* static function declarations */ #if 0 static int16_t rel_bord_lead(sbr_info *sbr, uint8_t ch, uint8_t l); static int16_t rel_bord_trail(sbr_info *sbr, uint8_t ch, uint8_t l); #endif static uint8_t middleBorder(sbr_info *sbr, uint8_t ch); /* function constructs new time border vector */ /* first build into temp vector to be able to use previous vector on error */ uint8_t envelope_time_border_vector(sbr_info *sbr, uint8_t ch) { uint8_t l, border, temp; uint8_t t_E_temp[6] = {0}; t_E_temp[0] = sbr->rate * sbr->abs_bord_lead[ch]; t_E_temp[sbr->L_E[ch]] = sbr->rate * sbr->abs_bord_trail[ch]; switch (sbr->bs_frame_class[ch]) { case FIXFIX: switch (sbr->L_E[ch]) { case 4: temp = (int) (sbr->numTimeSlots / 4); t_E_temp[3] = sbr->rate * 3 * temp; t_E_temp[2] = sbr->rate * 2 * temp; t_E_temp[1] = sbr->rate * temp; break; case 2: t_E_temp[1] = sbr->rate * (int) (sbr->numTimeSlots / 2); break; default: break; } break; case FIXVAR: if (sbr->L_E[ch] > 1) { int8_t i = sbr->L_E[ch]; border = sbr->abs_bord_trail[ch]; for (l = 0; l < (sbr->L_E[ch] - 1); l++) { if (border < sbr->bs_rel_bord[ch][l]) return 1; border -= sbr->bs_rel_bord[ch][l]; t_E_temp[--i] = sbr->rate * border; } } break; case VARFIX: if (sbr->L_E[ch] > 1) { int8_t i = 1; border = sbr->abs_bord_lead[ch]; for (l = 0; l < (sbr->L_E[ch] - 1); l++) { border += sbr->bs_rel_bord[ch][l]; if (sbr->rate * border + sbr->tHFAdj > sbr->numTimeSlotsRate+sbr->tHFGen) return 1; t_E_temp[i++] = sbr->rate * border; } } break; case VARVAR: if (sbr->bs_num_rel_0[ch]) { int8_t i = 1; border = sbr->abs_bord_lead[ch]; for (l = 0; l < sbr->bs_num_rel_0[ch]; l++) { border += sbr->bs_rel_bord_0[ch][l]; if (sbr->rate * border + sbr->tHFAdj > sbr->numTimeSlotsRate+sbr->tHFGen) return 1; t_E_temp[i++] = sbr->rate * border; } } if (sbr->bs_num_rel_1[ch]) { int8_t i = sbr->L_E[ch]; border = sbr->abs_bord_trail[ch]; for (l = 0; l < sbr->bs_num_rel_1[ch]; l++) { if (border < sbr->bs_rel_bord_1[ch][l]) return 1; border -= sbr->bs_rel_bord_1[ch][l]; t_E_temp[--i] = sbr->rate * border; } } break; } /* no error occured, we can safely use this t_E vector */ for (l = 0; l < 6; l++) { sbr->t_E[ch][l] = t_E_temp[l]; } return 0; } void noise_floor_time_border_vector(sbr_info *sbr, uint8_t ch) { sbr->t_Q[ch][0] = sbr->t_E[ch][0]; if (sbr->L_E[ch] == 1) { sbr->t_Q[ch][1] = sbr->t_E[ch][1]; sbr->t_Q[ch][2] = 0; } else { uint8_t index = middleBorder(sbr, ch); sbr->t_Q[ch][1] = sbr->t_E[ch][index]; sbr->t_Q[ch][2] = sbr->t_E[ch][sbr->L_E[ch]]; } } #if 0 static int16_t rel_bord_lead(sbr_info *sbr, uint8_t ch, uint8_t l) { uint8_t i; int16_t acc = 0; switch (sbr->bs_frame_class[ch]) { case FIXFIX: return sbr->numTimeSlots/sbr->L_E[ch]; case FIXVAR: return 0; case VARFIX: for (i = 0; i < l; i++) { acc += sbr->bs_rel_bord[ch][i]; } return acc; case VARVAR: for (i = 0; i < l; i++) { acc += sbr->bs_rel_bord_0[ch][i]; } return acc; } return 0; } static int16_t rel_bord_trail(sbr_info *sbr, uint8_t ch, uint8_t l) { uint8_t i; int16_t acc = 0; switch (sbr->bs_frame_class[ch]) { case FIXFIX: case VARFIX: return 0; case FIXVAR: for (i = 0; i < l; i++) { acc += sbr->bs_rel_bord[ch][i]; } return acc; case VARVAR: for (i = 0; i < l; i++) { acc += sbr->bs_rel_bord_1[ch][i]; } return acc; } return 0; } #endif static uint8_t middleBorder(sbr_info *sbr, uint8_t ch) { int8_t retval = 0; switch (sbr->bs_frame_class[ch]) { case FIXFIX: retval = sbr->L_E[ch]/2; break; case VARFIX: if (sbr->bs_pointer[ch] == 0) retval = 1; else if (sbr->bs_pointer[ch] == 1) retval = sbr->L_E[ch] - 1; else retval = sbr->bs_pointer[ch] - 1; break; case FIXVAR: case VARVAR: if (sbr->bs_pointer[ch] > 1) retval = sbr->L_E[ch] + 1 - sbr->bs_pointer[ch]; else retval = sbr->L_E[ch] - 1; break; } return (retval > 0) ? retval : 0; } #endif