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Diffstat (limited to 'src/libfaad/tns.c')
-rw-r--r-- | src/libfaad/tns.c | 306 |
1 files changed, 0 insertions, 306 deletions
diff --git a/src/libfaad/tns.c b/src/libfaad/tns.c deleted file mode 100644 index bb4db731a..000000000 --- a/src/libfaad/tns.c +++ /dev/null @@ -1,306 +0,0 @@ -/* -** FAAD2 - Freeware Advanced Audio (AAC) Decoder including SBR decoding -** Copyright (C) 2003-2004 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 1.8 2005/10/29 23:57:07 tmmm 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 = ics->swb_offset[start]; - - end = min(top, max_tns_sfb(sr_index, object_type, (ics->window_sequence == EIGHT_SHORT_SEQUENCE))); - end = min(end, ics->max_sfb); - end = ics->swb_offset[end]; - - 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 = ics->swb_offset[start]; - - end = min(top, max_tns_sfb(sr_index, object_type, (ics->window_sequence == EIGHT_SHORT_SEQUENCE))); - end = min(end, ics->max_sfb); - end = ics->swb_offset[end]; - - 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<m */ - b[i] = a[i] + MUL_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 is stored as a double ringbuffer */ - real_t state[2*TNS_MAX_ORDER] = {0}; - int8_t state_index = 0; - - for (i = 0; i < size; i++) - { - y = *spectrum; - - for (j = 0; j < order; j++) - y -= MUL_C(state[state_index+j], lpc[j+1]); - - /* double ringbuffer state */ - state_index--; - if (state_index < 0) - state_index = order-1; - state[state_index] = state[state_index + order] = y; - - *spectrum = y; - spectrum += inc; - -//#define TNS_PRINT -#ifdef TNS_PRINT - //printf("%d\n", y); - printf("0x%.8X\n", y); -#endif - } -} - -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 is stored as a double ringbuffer */ - real_t state[2*TNS_MAX_ORDER] = {0}; - int8_t state_index = 0; - - for (i = 0; i < size; i++) - { - y = *spectrum; - - for (j = 0; j < order; j++) - y += MUL_C(state[j], lpc[j+1]); - - /* double ringbuffer state */ - state_index--; - if (state_index < 0) - state_index = order-1; - state[state_index] = state[state_index + order] = *spectrum; - - *spectrum = y; - spectrum += inc; - } -} |