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author | arpi <arpi@b3059339-0415-0410-9bf9-f77b7e298cf2> | 2003-08-30 22:30:28 +0000 |
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committer | arpi <arpi@b3059339-0415-0410-9bf9-f77b7e298cf2> | 2003-08-30 22:30:28 +0000 |
commit | 32063c433915b8dddd143a951ad90ae901ac1b38 (patch) | |
tree | 88aaee983b0885b5bb22d870476f7afdaa8a7010 /libfaad2/tns.c | |
parent | 264633eec589baddfdcd79dde08fd7f1f47fba51 (diff) | |
download | mpv-32063c433915b8dddd143a951ad90ae901ac1b38.tar.bz2 mpv-32063c433915b8dddd143a951ad90ae901ac1b38.tar.xz |
libfaad2 v2.0rc1 imported
git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@10726 b3059339-0415-0410-9bf9-f77b7e298cf2
Diffstat (limited to 'libfaad2/tns.c')
-rw-r--r-- | libfaad2/tns.c | 303 |
1 files changed, 303 insertions, 0 deletions
diff --git a/libfaad2/tns.c b/libfaad2/tns.c new file mode 100644 index 0000000000..294cec4b6e --- /dev/null +++ b/libfaad2/tns.c @@ -0,0 +1,303 @@ +/* +** FAAD2 - Freeware Advanced Audio (AAC) Decoder including SBR decoding +** Copyright (C) 2003 M. Bakker, Ahead Software 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. +** +** Commercial non-GPL licensing of this software is possible. +** For more info contact Ahead Software through Mpeg4AAClicense@nero.com. +** +** $Id: tns.c,v 1.21 2003/07/29 08:20:14 menno Exp $ +**/ + +#include "common.h" +#include "structs.h" + +#include "syntax.h" +#include "tns.h" + +#ifdef FIXED_POINT +static real_t tns_coef_0_3[] = +{ + 0x0, 0x6F13013, 0xC8261BA, 0xF994E02, + 0xF03E3A3A, 0xF224C28C, 0xF5B72457, 0xFA8715E3, + 0xF90ECFED, 0xF37D9E46, 0xF066B1FE, 0xF066B1FE, + 0xF03E3A3A, 0xF224C28C, 0xF5B72457, 0xFA8715E3 +}; +static real_t tns_coef_0_4[] = +{ + 0x0, 0x3539B35, 0x681FE48, 0x9679182, + 0xBE3EBD4, 0xDDB3D74, 0xF378709, 0xFE98FCA, + 0xF011790B, 0xF09C5CB7, 0xF1AD6942, 0xF33B524A, + 0xF5388AEB, 0xF793BBDF, 0xFA385AA9, 0xFD0F5CAB +}; +static real_t tns_coef_1_3[] = +{ + 0x0, 0x6F13013, 0xF5B72457, 0xFA8715E3, + 0xF994E02, 0xC8261BA, 0xF5B72457, 0xFA8715E3, + 0xF90ECFED, 0xF37D9E46, 0xF5B72457, 0xFA8715E3, + 0xF37D9E46, 0xF90ECFED, 0xF5B72457, 0xFA8715E3 +}; +static real_t tns_coef_1_4[] = +{ + 0x0, 0x3539B35, 0x681FE48, 0x9679182, + 0xF5388AEB, 0xF793BBDF, 0xFA385AA9, 0xFD0F5CAB, + 0xFE98FCA, 0xF378709, 0xDDB3D74, 0xBE3EBD4, + 0xF5388AEB, 0xF793BBDF, 0xFA385AA9, 0xFD0F5CAB +}; +#else +#ifdef _MSC_VER +#pragma warning(disable:4305) +#pragma warning(disable:4244) +#endif +static real_t tns_coef_0_3[] = +{ + 0.0, 0.4338837391, 0.7818314825, 0.9749279122, + -0.9848077530, -0.8660254038, -0.6427876097, -0.3420201433, + -0.4338837391, -0.7818314825, -0.9749279122, -0.9749279122, + -0.9848077530, -0.8660254038, -0.6427876097, -0.3420201433 +}; +static real_t tns_coef_0_4[] = +{ + 0.0, 0.2079116908, 0.4067366431, 0.5877852523, + 0.7431448255, 0.8660254038, 0.9510565163, 0.9945218954, + -0.9957341763, -0.9618256432, -0.8951632914, -0.7980172273, + -0.6736956436, -0.5264321629, -0.3612416662, -0.1837495178 +}; +static real_t tns_coef_1_3[] = +{ + 0.0, 0.4338837391, -0.6427876097, -0.3420201433, + 0.9749279122, 0.7818314825, -0.6427876097, -0.3420201433, + -0.4338837391, -0.7818314825, -0.6427876097, -0.3420201433, + -0.7818314825, -0.4338837391, -0.6427876097, -0.3420201433 +}; +static real_t tns_coef_1_4[] = +{ + 0.0, 0.2079116908, 0.4067366431, 0.5877852523, + -0.6736956436, -0.5264321629, -0.3612416662, -0.1837495178, + 0.9945218954, 0.9510565163, 0.8660254038, 0.7431448255, + -0.6736956436, -0.5264321629, -0.3612416662, -0.1837495178 +}; +#endif + + +/* 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; + uint16_t bottom, top, start, end, size; + 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 = ics->swb_offset[min(bottom, ics->max_sfb)]; + end = ics->swb_offset[min(top, ics->max_sfb)]; + + if ((size = end - start) <= 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; + uint16_t bottom, top, start, end, size; + 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 = ics->swb_offset[min(bottom, ics->max_sfb)]; + end = ics->swb_offset[min(top, ics->max_sfb)]; + + if ((size = end - start) <= 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<m */ + b[i] = a[i] + MUL_C_C(tmp2[m-1], a[m-i]); + + for (i = 1; i < m; i++) /* loop only while i<m */ + a[i] = b[i]; + + a[m] = tmp2[m-1]; /* changed */ + } +} + +static void tns_ar_filter(real_t *spectrum, uint16_t size, int8_t inc, real_t *lpc, + uint8_t order) +{ + /* + - Simple all-pole filter of order "order" defined by + y(n) = x(n) - lpc[1]*y(n-1) - ... - lpc[order]*y(n-order) + - The state variables of the filter are initialized to zero every time + - The output data is written over the input data ("in-place operation") + - An input vector of "size" samples is processed and the index increment + to the next data sample is given by "inc" + */ + + uint8_t j; + uint16_t i; + real_t y, state[TNS_MAX_ORDER]; + + for (i = 0; i < order; i++) + state[i] = 0; + + for (i = 0; i < size; i++) + { + y = *spectrum; + + for (j = 0; j < order; j++) + y -= MUL_R_C(state[j], lpc[j+1]); + + for (j = order-1; j > 0; j--) + state[j] = state[j-1]; + + state[0] = y; + *spectrum = y; + spectrum += inc; + } +} + +static void tns_ma_filter(real_t *spectrum, uint16_t size, int8_t inc, real_t *lpc, + uint8_t order) +{ + /* + - Simple all-zero filter of order "order" defined by + y(n) = x(n) + a(2)*x(n-1) + ... + a(order+1)*x(n-order) + - The state variables of the filter are initialized to zero every time + - The output data is written over the input data ("in-place operation") + - An input vector of "size" samples is processed and the index increment + to the next data sample is given by "inc" + */ + + uint8_t j; + uint16_t i; + real_t y, state[TNS_MAX_ORDER]; + + for (i = 0; i < order; i++) + state[i] = REAL_CONST(0.0); + + for (i = 0; i < size; i++) + { + y = *spectrum; + + for (j = 0; j < order; j++) + y += MUL_R_C(state[j], lpc[j+1]); + + for (j = order-1; j > 0; j--) + state[j] = state[j-1]; + + state[0] = *spectrum; + *spectrum = y; + spectrum += inc; + } +} |