From cc2160de5cc05dc3aa77f3a34358e66f6193c8c9 Mon Sep 17 00:00:00 2001 From: Michał Cichoń Date: Tue, 26 Jun 2012 20:35:30 +0200 Subject: Add support for AAC. --- faad2/src/libfaad/tns.c | 309 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 309 insertions(+) create mode 100644 faad2/src/libfaad/tns.c (limited to 'faad2/src/libfaad/tns.c') diff --git a/faad2/src/libfaad/tns.c b/faad2/src/libfaad/tns.c new file mode 100644 index 0000000..20538e3 --- /dev/null +++ b/faad2/src/libfaad/tns.c @@ -0,0 +1,309 @@ +/* +** 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. +** +** The "appropriate copyright message" mentioned in section 2c of the GPLv2 +** must read: "Code from FAAD2 is copyright (c) Nero AG, www.nero.com" +** +** Commercial non-GPL licensing of this software is possible. +** For more info contact Nero AG through Mpeg4AAClicense@nero.com. +** +** $Id: tns.c,v 1.40 2007/11/01 12:33:40 menno Exp $ +**/ + +#include "common.h" +#include "structs.h" + +#include "syntax.h" +#include "tns.h" + + +/* static function declarations */ +static void tns_decode_coef(uint8_t order, uint8_t coef_res_bits, uint8_t coef_compress, + uint8_t *coef, real_t *a); +static void tns_ar_filter(real_t *spectrum, uint16_t size, int8_t inc, real_t *lpc, + uint8_t order); +static void tns_ma_filter(real_t *spectrum, uint16_t size, int8_t inc, real_t *lpc, + uint8_t order); + + +#ifdef _MSC_VER +#pragma warning(disable:4305) +#pragma warning(disable:4244) +#endif +static real_t tns_coef_0_3[] = +{ + COEF_CONST(0.0), COEF_CONST(0.4338837391), COEF_CONST(0.7818314825), COEF_CONST(0.9749279122), + COEF_CONST(-0.9848077530), COEF_CONST(-0.8660254038), COEF_CONST(-0.6427876097), COEF_CONST(-0.3420201433), + COEF_CONST(-0.4338837391), COEF_CONST(-0.7818314825), COEF_CONST(-0.9749279122), COEF_CONST(-0.9749279122), + COEF_CONST(-0.9848077530), COEF_CONST(-0.8660254038), COEF_CONST(-0.6427876097), COEF_CONST(-0.3420201433) +}; +static real_t tns_coef_0_4[] = +{ + COEF_CONST(0.0), COEF_CONST(0.2079116908), COEF_CONST(0.4067366431), COEF_CONST(0.5877852523), + COEF_CONST(0.7431448255), COEF_CONST(0.8660254038), COEF_CONST(0.9510565163), COEF_CONST(0.9945218954), + COEF_CONST(-0.9957341763), COEF_CONST(-0.9618256432), COEF_CONST(-0.8951632914), COEF_CONST(-0.7980172273), + COEF_CONST(-0.6736956436), COEF_CONST(-0.5264321629), COEF_CONST(-0.3612416662), COEF_CONST(-0.1837495178) +}; +static real_t tns_coef_1_3[] = +{ + COEF_CONST(0.0), COEF_CONST(0.4338837391), COEF_CONST(-0.6427876097), COEF_CONST(-0.3420201433), + COEF_CONST(0.9749279122), COEF_CONST(0.7818314825), COEF_CONST(-0.6427876097), COEF_CONST(-0.3420201433), + COEF_CONST(-0.4338837391), COEF_CONST(-0.7818314825), COEF_CONST(-0.6427876097), COEF_CONST(-0.3420201433), + COEF_CONST(-0.7818314825), COEF_CONST(-0.4338837391), COEF_CONST(-0.6427876097), COEF_CONST(-0.3420201433) +}; +static real_t tns_coef_1_4[] = +{ + COEF_CONST(0.0), COEF_CONST(0.2079116908), COEF_CONST(0.4067366431), COEF_CONST(0.5877852523), + COEF_CONST(-0.6736956436), COEF_CONST(-0.5264321629), COEF_CONST(-0.3612416662), COEF_CONST(-0.1837495178), + COEF_CONST(0.9945218954), COEF_CONST(0.9510565163), COEF_CONST(0.8660254038), COEF_CONST(0.7431448255), + COEF_CONST(-0.6736956436), COEF_CONST(-0.5264321629), COEF_CONST(-0.3612416662), COEF_CONST(-0.1837495178) +}; + + +/* TNS decoding for one channel and frame */ +void tns_decode_frame(ic_stream *ics, tns_info *tns, uint8_t sr_index, + uint8_t object_type, real_t *spec, uint16_t frame_len) +{ + uint8_t w, f, tns_order; + int8_t inc; + int16_t size; + uint16_t bottom, top, start, end; + uint16_t nshort = frame_len/8; + real_t lpc[TNS_MAX_ORDER+1]; + + if (!ics->tns_data_present) + return; + + for (w = 0; w < ics->num_windows; w++) + { + bottom = ics->num_swb; + + for (f = 0; f < tns->n_filt[w]; f++) + { + top = bottom; + bottom = max(top - tns->length[w][f], 0); + tns_order = min(tns->order[w][f], TNS_MAX_ORDER); + if (!tns_order) + continue; + + tns_decode_coef(tns_order, tns->coef_res[w]+3, + tns->coef_compress[w][f], tns->coef[w][f], lpc); + + start = min(bottom, max_tns_sfb(sr_index, object_type, (ics->window_sequence == EIGHT_SHORT_SEQUENCE))); + start = min(start, ics->max_sfb); + start = min(ics->swb_offset[start], ics->swb_offset_max); + + end = min(top, max_tns_sfb(sr_index, object_type, (ics->window_sequence == EIGHT_SHORT_SEQUENCE))); + end = min(end, ics->max_sfb); + end = min(ics->swb_offset[end], ics->swb_offset_max); + + size = end - start; + if (size <= 0) + continue; + + if (tns->direction[w][f]) + { + inc = -1; + start = end - 1; + } else { + inc = 1; + } + + tns_ar_filter(&spec[(w*nshort)+start], size, inc, lpc, tns_order); + } + } +} + +/* TNS encoding for one channel and frame */ +void tns_encode_frame(ic_stream *ics, tns_info *tns, uint8_t sr_index, + uint8_t object_type, real_t *spec, uint16_t frame_len) +{ + uint8_t w, f, tns_order; + int8_t inc; + int16_t size; + uint16_t bottom, top, start, end; + uint16_t nshort = frame_len/8; + real_t lpc[TNS_MAX_ORDER+1]; + + if (!ics->tns_data_present) + return; + + for (w = 0; w < ics->num_windows; w++) + { + bottom = ics->num_swb; + + for (f = 0; f < tns->n_filt[w]; f++) + { + top = bottom; + bottom = max(top - tns->length[w][f], 0); + tns_order = min(tns->order[w][f], TNS_MAX_ORDER); + if (!tns_order) + continue; + + tns_decode_coef(tns_order, tns->coef_res[w]+3, + tns->coef_compress[w][f], tns->coef[w][f], lpc); + + start = min(bottom, max_tns_sfb(sr_index, object_type, (ics->window_sequence == EIGHT_SHORT_SEQUENCE))); + start = min(start, ics->max_sfb); + start = min(ics->swb_offset[start], ics->swb_offset_max); + + end = min(top, max_tns_sfb(sr_index, object_type, (ics->window_sequence == EIGHT_SHORT_SEQUENCE))); + end = min(end, ics->max_sfb); + end = min(ics->swb_offset[end], ics->swb_offset_max); + + size = end - start; + if (size <= 0) + continue; + + if (tns->direction[w][f]) + { + inc = -1; + start = end - 1; + } else { + inc = 1; + } + + tns_ma_filter(&spec[(w*nshort)+start], size, inc, lpc, tns_order); + } + } +} + +/* Decoder transmitted coefficients for one TNS filter */ +static void tns_decode_coef(uint8_t order, uint8_t coef_res_bits, uint8_t coef_compress, + uint8_t *coef, real_t *a) +{ + uint8_t i, m; + real_t tmp2[TNS_MAX_ORDER+1], b[TNS_MAX_ORDER+1]; + + /* Conversion to signed integer */ + for (i = 0; i < order; i++) + { + if (coef_compress == 0) + { + if (coef_res_bits == 3) + { + tmp2[i] = tns_coef_0_3[coef[i]]; + } else { + tmp2[i] = tns_coef_0_4[coef[i]]; + } + } else { + if (coef_res_bits == 3) + { + tmp2[i] = tns_coef_1_3[coef[i]]; + } else { + tmp2[i] = tns_coef_1_4[coef[i]]; + } + } + } + + /* Conversion to LPC coefficients */ + a[0] = COEF_CONST(1.0); + for (m = 1; m <= order; m++) + { + for (i = 1; i < m; i++) /* loop only while i