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-rw-r--r--faad2/src/libfaad/pns.c271
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diff --git a/faad2/src/libfaad/pns.c b/faad2/src/libfaad/pns.c
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--- a/faad2/src/libfaad/pns.c
+++ /dev/null
@@ -1,271 +0,0 @@
-/*
-** 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: pns.c,v 1.38 2007/11/01 12:33:32 menno Exp $
-**/
-
-#include "common.h"
-#include "structs.h"
-
-#include "pns.h"
-
-
-/* static function declarations */
-static void gen_rand_vector(real_t *spec, int16_t scale_factor, uint16_t size,
- uint8_t sub,
- /* RNG states */ uint32_t *__r1, uint32_t *__r2);
-
-
-#ifdef FIXED_POINT
-
-#define DIV(A, B) (((int64_t)A << REAL_BITS)/B)
-
-#define step(shift) \
- if ((0x40000000l >> shift) + root <= value) \
- { \
- value -= (0x40000000l >> shift) + root; \
- root = (root >> 1) | (0x40000000l >> shift); \
- } else { \
- root = root >> 1; \
- }
-
-/* fixed point square root approximation */
-/* !!!! ONLY WORKS FOR EVEN %REAL_BITS% !!!! */
-real_t fp_sqrt(real_t value)
-{
- real_t root = 0;
-
- step( 0); step( 2); step( 4); step( 6);
- step( 8); step(10); step(12); step(14);
- step(16); step(18); step(20); step(22);
- step(24); step(26); step(28); step(30);
-
- if (root < value)
- ++root;
-
- root <<= (REAL_BITS/2);
-
- return root;
-}
-
-static real_t const pow2_table[] =
-{
- COEF_CONST(1.0),
- COEF_CONST(1.18920711500272),
- COEF_CONST(1.41421356237310),
- COEF_CONST(1.68179283050743)
-};
-#endif
-
-/* The function gen_rand_vector(addr, size) generates a vector of length
- <size> with signed random values of average energy MEAN_NRG per random
- value. A suitable random number generator can be realized using one
- multiplication/accumulation per random value.
-*/
-static INLINE void gen_rand_vector(real_t *spec, int16_t scale_factor, uint16_t size,
- uint8_t sub,
- /* RNG states */ uint32_t *__r1, uint32_t *__r2)
-{
-#ifndef FIXED_POINT
- uint16_t i;
- real_t energy = 0.0;
-
- real_t scale = (real_t)1.0/(real_t)size;
-
- for (i = 0; i < size; i++)
- {
- real_t tmp = scale*(real_t)(int32_t)ne_rng(__r1, __r2);
- spec[i] = tmp;
- energy += tmp*tmp;
- }
-
- scale = (real_t)1.0/(real_t)sqrt(energy);
- scale *= (real_t)pow(2.0, 0.25 * scale_factor);
- for (i = 0; i < size; i++)
- {
- spec[i] *= scale;
- }
-#else
- uint16_t i;
- real_t energy = 0, scale;
- int32_t exp, frac;
-
- for (i = 0; i < size; i++)
- {
- /* this can be replaced by a 16 bit random generator!!!! */
- real_t tmp = (int32_t)ne_rng(__r1, __r2);
- if (tmp < 0)
- tmp = -(tmp & ((1<<(REAL_BITS-1))-1));
- else
- tmp = (tmp & ((1<<(REAL_BITS-1))-1));
-
- energy += MUL_R(tmp,tmp);
-
- spec[i] = tmp;
- }
-
- energy = fp_sqrt(energy);
- if (energy > 0)
- {
- scale = DIV(REAL_CONST(1),energy);
-
- exp = scale_factor >> 2;
- frac = scale_factor & 3;
-
- /* IMDCT pre-scaling */
- exp -= sub;
-
- if (exp < 0)
- scale >>= -exp;
- else
- scale <<= exp;
-
- if (frac)
- scale = MUL_C(scale, pow2_table[frac]);
-
- for (i = 0; i < size; i++)
- {
- spec[i] = MUL_R(spec[i], scale);
- }
- }
-#endif
-}
-
-void pns_decode(ic_stream *ics_left, ic_stream *ics_right,
- real_t *spec_left, real_t *spec_right, uint16_t frame_len,
- uint8_t channel_pair, uint8_t object_type,
- /* RNG states */ uint32_t *__r1, uint32_t *__r2)
-{
- uint8_t g, sfb, b;
- uint16_t size, offs;
-
- uint8_t group = 0;
- uint16_t nshort = frame_len >> 3;
-
- uint8_t sub = 0;
-
-#ifdef FIXED_POINT
- /* IMDCT scaling */
- if (object_type == LD)
- {
- sub = 9 /*9*/;
- } else {
- if (ics_left->window_sequence == EIGHT_SHORT_SEQUENCE)
- sub = 7 /*7*/;
- else
- sub = 10 /*10*/;
- }
-#endif
-
- for (g = 0; g < ics_left->num_window_groups; g++)
- {
- /* Do perceptual noise substitution decoding */
- for (b = 0; b < ics_left->window_group_length[g]; b++)
- {
- for (sfb = 0; sfb < ics_left->max_sfb; sfb++)
- {
- if (is_noise(ics_left, g, sfb))
- {
-#ifdef LTP_DEC
- /* Simultaneous use of LTP and PNS is not prevented in the
- syntax. If both LTP, and PNS are enabled on the same
- scalefactor band, PNS takes precedence, and no prediction
- is applied to this band.
- */
- ics_left->ltp.long_used[sfb] = 0;
- ics_left->ltp2.long_used[sfb] = 0;
-#endif
-
-#ifdef MAIN_DEC
- /* For scalefactor bands coded using PNS the corresponding
- predictors are switched to "off".
- */
- ics_left->pred.prediction_used[sfb] = 0;
-#endif
-
- offs = ics_left->swb_offset[sfb];
- size = min(ics_left->swb_offset[sfb+1], ics_left->swb_offset_max) - offs;
-
- /* Generate random vector */
- gen_rand_vector(&spec_left[(group*nshort)+offs],
- ics_left->scale_factors[g][sfb], size, sub, __r1, __r2);
- }
-
-/* From the spec:
- If the same scalefactor band and group is coded by perceptual noise
- substitution in both channels of a channel pair, the correlation of
- the noise signal can be controlled by means of the ms_used field: While
- the default noise generation process works independently for each channel
- (separate generation of random vectors), the same random vector is used
- for both channels if ms_used[] is set for a particular scalefactor band
- and group. In this case, no M/S stereo coding is carried out (because M/S
- stereo coding and noise substitution coding are mutually exclusive).
- If the same scalefactor band and group is coded by perceptual noise
- substitution in only one channel of a channel pair the setting of ms_used[]
- is not evaluated.
-*/
- if (channel_pair)
- {
- if (is_noise(ics_right, g, sfb))
- {
- if (((ics_left->ms_mask_present == 1) &&
- (ics_left->ms_used[g][sfb])) ||
- (ics_left->ms_mask_present == 2))
- {
- uint16_t c;
-
- offs = ics_right->swb_offset[sfb];
- size = min(ics_right->swb_offset[sfb+1], ics_right->swb_offset_max) - offs;
-
- for (c = 0; c < size; c++)
- {
- spec_right[(group*nshort) + offs + c] =
- spec_left[(group*nshort) + offs + c];
- }
- } else /*if (ics_left->ms_mask_present == 0)*/ {
-#ifdef LTP_DEC
- ics_right->ltp.long_used[sfb] = 0;
- ics_right->ltp2.long_used[sfb] = 0;
-#endif
-#ifdef MAIN_DEC
- ics_right->pred.prediction_used[sfb] = 0;
-#endif
-
- offs = ics_right->swb_offset[sfb];
- size = min(ics_right->swb_offset[sfb+1], ics_right->swb_offset_max) - offs;
-
- /* Generate random vector */
- gen_rand_vector(&spec_right[(group*nshort)+offs],
- ics_right->scale_factors[g][sfb], size, sub, __r1, __r2);
- }
- }
- }
- } /* sfb */
- group++;
- } /* b */
- } /* g */
-}