/*

** 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: specrec.c,v 1.63 2010/06/04 20:47:56 menno Exp $

**/

/*

  Spectral reconstruction:

   - grouping/sectioning

   - inverse quantization

   - applying scalefactors

*/

#include "common.h"

#include "structs.h"

#include <stdlib.h>

#include "specrec.h"

#include "filtbank.h"

#include "syntax.h"

#include "iq_table.h"

#include "ms.h"

#include "is.h"

#include "pns.h"

#include "tns.h"

#include "drc.h"

#include "lt_predict.h"

#include "ic_predict.h"

#ifdef SSR_DEC

#include "ssr.h"

#include "ssr_fb.h"

#endif

/* static function declarations */

static uint8_t quant_to_spec(NeAACDecStruct *hDecoder,

                             ic_stream *ics, int16_t *quant_data,

                             real_t *spec_data, uint16_t frame_len);

#ifdef LD_DEC

ALIGN static const uint8_t num_swb_512_window[] =

{

    0, 0, 0, 36, 36, 37, 31, 31, 0, 0, 0, 0

};

ALIGN static const uint8_t num_swb_480_window[] =

{

    0, 0, 0, 35, 35, 37, 30, 30, 0, 0, 0, 0

};

#endif

ALIGN static const uint8_t num_swb_960_window[] =

{

    40, 40, 45, 49, 49, 49, 46, 46, 42, 42, 42, 40

};

ALIGN static const uint8_t num_swb_1024_window[] =

{

    41, 41, 47, 49, 49, 51, 47, 47, 43, 43, 43, 40

};

ALIGN static const uint8_t num_swb_128_window[] =

{

    12, 12, 12, 14, 14, 14, 15, 15, 15, 15, 15, 15

};

ALIGN static const uint16_t swb_offset_1024_96[] =

{

    0, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 52, 56,

    64, 72, 80, 88, 96, 108, 120, 132, 144, 156, 172, 188, 212, 240,

    276, 320, 384, 448, 512, 576, 640, 704, 768, 832, 896, 960, 1024

};

ALIGN static const uint16_t swb_offset_128_96[] =

{

    0, 4, 8, 12, 16, 20, 24, 32, 40, 48, 64, 92, 128

};

ALIGN static const uint16_t swb_offset_1024_64[] =

{

    0, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 52, 56,

    64, 72, 80, 88, 100, 112, 124, 140, 156, 172, 192, 216, 240, 268,

    304, 344, 384, 424, 464, 504, 544, 584, 624, 664, 704, 744, 784, 824,

    864, 904, 944, 984, 1024

};

ALIGN static const uint16_t swb_offset_128_64[] =

{

    0, 4, 8, 12, 16, 20, 24, 32, 40, 48, 64, 92, 128

};

ALIGN static const uint16_t swb_offset_1024_48[] =

{

    0, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 48, 56, 64, 72,

    80, 88, 96, 108, 120, 132, 144, 160, 176, 196, 216, 240, 264, 292,

    320, 352, 384, 416, 448, 480, 512, 544, 576, 608, 640, 672, 704, 736,

    768, 800, 832, 864, 896, 928, 1024

};

#ifdef LD_DEC

ALIGN static const uint16_t swb_offset_512_48[] =

{

    0, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 52, 56, 60, 68, 76, 84,

    92, 100, 112, 124, 136, 148, 164, 184, 208, 236, 268, 300, 332, 364, 396,

    428, 460, 512

};

ALIGN static const uint16_t swb_offset_480_48[] =

{

    0, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 52, 56, 64, 72 ,80 ,88,

    96, 108, 120, 132, 144, 156, 172, 188, 212, 240, 272, 304, 336, 368, 400,

    432, 480

};

#endif

ALIGN static const uint16_t swb_offset_128_48[] =

{

    0, 4, 8, 12, 16, 20, 28, 36, 44, 56, 68, 80, 96, 112, 128

};

ALIGN static const uint16_t swb_offset_1024_32[] =

{

    0, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 48, 56, 64, 72,

    80, 88, 96, 108, 120, 132, 144, 160, 176, 196, 216, 240, 264, 292,

    320, 352, 384, 416, 448, 480, 512, 544, 576, 608, 640, 672, 704, 736,

    768, 800, 832, 864, 896, 928, 960, 992, 1024

};

#ifdef LD_DEC

ALIGN static const uint16_t swb_offset_512_32[] =

{

    0, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 52, 56, 64, 72, 80,

    88, 96, 108, 120, 132, 144, 160, 176, 192, 212, 236, 260, 288, 320, 352,

    384, 416, 448, 480, 512

};

ALIGN static const uint16_t swb_offset_480_32[] =

{

    0, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 52, 56, 60, 64, 72, 80,

    88, 96, 104, 112, 124, 136, 148, 164, 180, 200, 224, 256, 288, 320, 352,

    384, 416, 448, 480

};

#endif

ALIGN static const uint16_t swb_offset_1024_24[] =

{

    0, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 52, 60, 68,

    76, 84, 92, 100, 108, 116, 124, 136, 148, 160, 172, 188, 204, 220,

    240, 260, 284, 308, 336, 364, 396, 432, 468, 508, 552, 600, 652, 704,

    768, 832, 896, 960, 1024

};

#ifdef LD_DEC

ALIGN static const uint16_t swb_offset_512_24[] =

{

    0, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 52, 60, 68,

    80, 92, 104, 120, 140, 164, 192, 224, 256, 288, 320, 352, 384, 416,

    448, 480, 512

};

ALIGN static const uint16_t swb_offset_480_24[] =

{

    0, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 52, 60, 68, 80, 92, 104, 120,

    140, 164, 192, 224, 256, 288, 320, 352, 384, 416, 448, 480

};

#endif

ALIGN static const uint16_t swb_offset_128_24[] =

{

    0, 4, 8, 12, 16, 20, 24, 28, 36, 44, 52, 64, 76, 92, 108, 128

};

ALIGN static const uint16_t swb_offset_1024_16[] =

{

    0, 8, 16, 24, 32, 40, 48, 56, 64, 72, 80, 88, 100, 112, 124,

    136, 148, 160, 172, 184, 196, 212, 228, 244, 260, 280, 300, 320, 344,

    368, 396, 424, 456, 492, 532, 572, 616, 664, 716, 772, 832, 896, 960, 1024

};

ALIGN static const uint16_t swb_offset_128_16[] =

{

    0, 4, 8, 12, 16, 20, 24, 28, 32, 40, 48, 60, 72, 88, 108, 128

};

ALIGN static const uint16_t swb_offset_1024_8[] =

{

    0, 12, 24, 36, 48, 60, 72, 84, 96, 108, 120, 132, 144, 156, 172,

    188, 204, 220, 236, 252, 268, 288, 308, 328, 348, 372, 396, 420, 448,

    476, 508, 544, 580, 620, 664, 712, 764, 820, 880, 944, 1024

};

ALIGN static const uint16_t swb_offset_128_8[] =

{

    0, 4, 8, 12, 16, 20, 24, 28, 36, 44, 52, 60, 72, 88, 108, 128

};

ALIGN static const uint16_t *swb_offset_1024_window[] =

{

    swb_offset_1024_96,      /* 96000 */

    swb_offset_1024_96,      /* 88200 */

    swb_offset_1024_64,      /* 64000 */

    swb_offset_1024_48,      /* 48000 */

    swb_offset_1024_48,      /* 44100 */

    swb_offset_1024_32,      /* 32000 */

    swb_offset_1024_24,      /* 24000 */

    swb_offset_1024_24,      /* 22050 */

    swb_offset_1024_16,      /* 16000 */

    swb_offset_1024_16,      /* 12000 */

    swb_offset_1024_16,      /* 11025 */

    swb_offset_1024_8        /* 8000  */

};

#ifdef LD_DEC

ALIGN static const uint16_t *swb_offset_512_window[] =

{

    0,                       /* 96000 */

    0,                       /* 88200 */

    0,                       /* 64000 */

    swb_offset_512_48,       /* 48000 */

    swb_offset_512_48,       /* 44100 */

    swb_offset_512_32,       /* 32000 */

    swb_offset_512_24,       /* 24000 */

    swb_offset_512_24,       /* 22050 */

    0,                       /* 16000 */

    0,                       /* 12000 */

    0,                       /* 11025 */

    0                        /* 8000  */

};

ALIGN static const uint16_t *swb_offset_480_window[] =

{

    0,                       /* 96000 */

    0,                       /* 88200 */

    0,                       /* 64000 */

    swb_offset_480_48,       /* 48000 */

    swb_offset_480_48,       /* 44100 */

    swb_offset_480_32,       /* 32000 */

    swb_offset_480_24,       /* 24000 */

    swb_offset_480_24,       /* 22050 */

    0,                       /* 16000 */

    0,                       /* 12000 */

    0,                       /* 11025 */

    0                        /* 8000  */

};

#endif

ALIGN static const  uint16_t *swb_offset_128_window[] =

{

    swb_offset_128_96,       /* 96000 */

    swb_offset_128_96,       /* 88200 */

    swb_offset_128_64,       /* 64000 */

    swb_offset_128_48,       /* 48000 */

    swb_offset_128_48,       /* 44100 */

    swb_offset_128_48,       /* 32000 */

    swb_offset_128_24,       /* 24000 */

    swb_offset_128_24,       /* 22050 */

    swb_offset_128_16,       /* 16000 */

    swb_offset_128_16,       /* 12000 */

    swb_offset_128_16,       /* 11025 */

    swb_offset_128_8         /* 8000  */

};

#define bit_set(A, B) ((A) & (1<<(B)))

/* 4.5.2.3.4 */

/*

  - determine the number of windows in a window_sequence named num_windows

  - determine the number of window_groups named num_window_groups

  - determine the number of windows in each group named window_group_length[g]

  - determine the total number of scalefactor window bands named num_swb for

    the actual window type

  - determine swb_offset[swb], the offset of the first coefficient in

    scalefactor window band named swb of the window actually used

  - determine sect_sfb_offset[g][section],the offset of the first coefficient

    in section named section. This offset depends on window_sequence and

    scale_factor_grouping and is needed to decode the spectral_data().

*/

uint8_t window_grouping_info(NeAACDecStruct *hDecoder, ic_stream *ics)

{

    uint8_t i, g;

    uint8_t sf_index = hDecoder->sf_index;

    if (sf_index >= 12)

        return 32;

    switch (ics->window_sequence) {

    case ONLY_LONG_SEQUENCE:

    case LONG_START_SEQUENCE:

    case LONG_STOP_SEQUENCE:

        ics->num_windows = 1;

        ics->num_window_groups = 1;

        ics->window_group_length[ics->num_window_groups-1] = 1;

#ifdef LD_DEC

        if (hDecoder->object_type == LD)

        {

            if (hDecoder->frameLength == 512)

                ics->num_swb = num_swb_512_window[sf_index];

            else /* if (hDecoder->frameLength == 480) */

                ics->num_swb = num_swb_480_window[sf_index];

        } else {

#endif

            if (hDecoder->frameLength == 1024)

                ics->num_swb = num_swb_1024_window[sf_index];

            else /* if (hDecoder->frameLength == 960) */

                ics->num_swb = num_swb_960_window[sf_index];

#ifdef LD_DEC

        }

#endif

        if (ics->max_sfb > ics->num_swb)

        {

            return 32;

        }

        /* preparation of sect_sfb_offset for long blocks */

        /* also copy the last value! */

#ifdef LD_DEC

        if (hDecoder->object_type == LD)

        {

            if (hDecoder->frameLength == 512)

            {

                for (i = 0; i < ics->num_swb; i++)

                {

                    ics->sect_sfb_offset[0][i] = swb_offset_512_window[sf_index][i];

                    ics->swb_offset[i] = swb_offset_512_window[sf_index][i];

                }

            } else /* if (hDecoder->frameLength == 480) */ {

                for (i = 0; i < ics->num_swb; i++)

                {

                    ics->sect_sfb_offset[0][i] = swb_offset_480_window[sf_index][i];

                    ics->swb_offset[i] = swb_offset_480_window[sf_index][i];

                }

            }

            ics->sect_sfb_offset[0][ics->num_swb] = hDecoder->frameLength;

            ics->swb_offset[ics->num_swb] = hDecoder->frameLength;

            ics->swb_offset_max = hDecoder->frameLength;

        } else {

#endif

            for (i = 0; i < ics->num_swb; i++)

            {

                ics->sect_sfb_offset[0][i] = swb_offset_1024_window[sf_index][i];

                ics->swb_offset[i] = swb_offset_1024_window[sf_index][i];

            }

            ics->sect_sfb_offset[0][ics->num_swb] = hDecoder->frameLength;

            ics->swb_offset[ics->num_swb] = hDecoder->frameLength;

            ics->swb_offset_max = hDecoder->frameLength;

#ifdef LD_DEC

        }

#endif

        return 0;

    case EIGHT_SHORT_SEQUENCE:

        ics->num_windows = 8;

        ics->num_window_groups = 1;

        ics->window_group_length[ics->num_window_groups-1] = 1;

        ics->num_swb = num_swb_128_window[sf_index];

        if (ics->max_sfb > ics->num_swb)

        {

            return 32;

        }

        for (i = 0; i < ics->num_swb; i++)

            ics->swb_offset[i] = swb_offset_128_window[sf_index][i];

        ics->swb_offset[ics->num_swb] = hDecoder->frameLength/8;

        ics->swb_offset_max = hDecoder->frameLength/8;

        for (i = 0; i < ics->num_windows-1; i++) {

            if (bit_set(ics->scale_factor_grouping, 6-i) == 0)

            {

                ics->num_window_groups += 1;

                ics->window_group_length[ics->num_window_groups-1] = 1;

            } else {

                ics->window_group_length[ics->num_window_groups-1] += 1;

            }

        }

        /* preparation of sect_sfb_offset for short blocks */

        for (g = 0; g < ics->num_window_groups; g++)

        {

            uint16_t width;

            uint8_t sect_sfb = 0;

            uint16_t offset = 0;

            for (i = 0; i < ics->num_swb; i++)

            {

                if (i+1 == ics->num_swb)

                {

                    width = (hDecoder->frameLength/8) - swb_offset_128_window[sf_index][i];

                } else {

                    width = swb_offset_128_window[sf_index][i+1] -

                        swb_offset_128_window[sf_index][i];

                }

                width *= ics->window_group_length[g];

                ics->sect_sfb_offset[g][sect_sfb++] = offset;

                offset += width;

            }

            ics->sect_sfb_offset[g][sect_sfb] = offset;

        }

        return 0;

    default:

        return 32;

    }

}

/* iquant() * output = sign(input)*abs(input)^(4/3) */

static INLINE real_t iquant(int16_t q, const real_t *tab, uint8_t *error)

{

#ifdef FIXED_POINT

/* For FIXED_POINT the iq_table is prescaled by 3 bits (iq_table[]/8) */

/* BIG_IQ_TABLE allows you to use the full 8192 value table, if this is not

 * defined a 1026 value table and interpolation will be used

 */

#ifndef BIG_IQ_TABLE

    static const real_t errcorr[] = {

        REAL_CONST(0), REAL_CONST(1.0/8.0), REAL_CONST(2.0/8.0), REAL_CONST(3.0/8.0),

        REAL_CONST(4.0/8.0),  REAL_CONST(5.0/8.0), REAL_CONST(6.0/8.0), REAL_CONST(7.0/8.0),

        REAL_CONST(0)

    };

    real_t x1, x2;

#endif

    int16_t sgn = 1;

    if (q < 0)

    {

        q = -q;

        sgn = -1;

    }

    if (q < IQ_TABLE_SIZE)

    {

//#define IQUANT_PRINT

#ifdef IQUANT_PRINT

        //printf("0x%.8X\n", sgn * tab[q]);

        printf("%d\n", sgn * tab[q]);

#endif

        return sgn * tab[q];

    }

#ifndef BIG_IQ_TABLE

    if (q >= 8192)

    {

        *error = 17;

        return 0;

    }

    /* linear interpolation */

    x1 = tab[q>>3];

    x2 = tab[(q>>3) + 1];

    return sgn * 16 * (MUL_R(errcorr[q&7],(x2-x1)) + x1);

#else

    *error = 17;

    return 0;

#endif

#else

    if (q < 0)

    {

        /* tab contains a value for all possible q [0,8192] */

        if (-q < IQ_TABLE_SIZE)

            return -tab[-q];

        *error = 17;

        return 0;

    } else {

        /* tab contains a value for all possible q [0,8192] */

        if (q < IQ_TABLE_SIZE)

            return tab[q];

        *error = 17;

        return 0;

    }

#endif

}

#ifndef FIXED_POINT

ALIGN static const real_t pow2sf_tab[] = {

    2.9802322387695313E-008, 5.9604644775390625E-008, 1.1920928955078125E-007,

    2.384185791015625E-007, 4.76837158203125E-007, 9.5367431640625E-007,

    1.9073486328125E-006, 3.814697265625E-006, 7.62939453125E-006,

    1.52587890625E-005, 3.0517578125E-005, 6.103515625E-005,

    0.0001220703125, 0.000244140625, 0.00048828125,

    0.0009765625, 0.001953125, 0.00390625,

    0.0078125, 0.015625, 0.03125,

    0.0625, 0.125, 0.25,

    0.5, 1.0, 2.0,

    4.0, 8.0, 16.0, 32.0,

    64.0, 128.0, 256.0,

    512.0, 1024.0, 2048.0,

    4096.0, 8192.0, 16384.0,

    32768.0, 65536.0, 131072.0,

    262144.0, 524288.0, 1048576.0,

    2097152.0, 4194304.0, 8388608.0,

    16777216.0, 33554432.0, 67108864.0,

    134217728.0, 268435456.0, 536870912.0,

    1073741824.0, 2147483648.0, 4294967296.0,

    8589934592.0, 17179869184.0, 34359738368.0,

    68719476736.0, 137438953472.0, 274877906944.0

};

#endif

/* quant_to_spec: perform dequantisation and scaling

 * and in case of short block it also does the deinterleaving

 */

/*

  For ONLY_LONG_SEQUENCE windows (num_window_groups = 1,

  window_group_length[0] = 1) the spectral data is in ascending spectral

  order.

  For the EIGHT_SHORT_SEQUENCE window, the spectral order depends on the

  grouping in the following manner:

  - Groups are ordered sequentially

  - Within a group, a scalefactor band consists of the spectral data of all

    grouped SHORT_WINDOWs for the associated scalefactor window band. To

    clarify via example, the length of a group is in the range of one to eight

    SHORT_WINDOWs.

  - If there are eight groups each with length one (num_window_groups = 8,

    window_group_length[0..7] = 1), the result is a sequence of eight spectra,

    each in ascending spectral order.

  - If there is only one group with length eight (num_window_groups = 1,

    window_group_length[0] = 8), the result is that spectral data of all eight

    SHORT_WINDOWs is interleaved by scalefactor window bands.

  - Within a scalefactor window band, the coefficients are in ascending

    spectral order.

*/

static uint8_t quant_to_spec(NeAACDecStruct *hDecoder,

                             ic_stream *ics, int16_t *quant_data,

                             real_t *spec_data, uint16_t frame_len)

{

    ALIGN static const real_t pow2_table[] =

    {

        COEF_CONST(1.0),

        COEF_CONST(1.1892071150027210667174999705605), /* 2^0.25 */

        COEF_CONST(1.4142135623730950488016887242097), /* 2^0.5 */

        COEF_CONST(1.6817928305074290860622509524664) /* 2^0.75 */

    };

    const real_t *tab = iq_table;

    uint8_t g, sfb, win;

    uint16_t width, bin, k, gindex;

    uint8_t error = 0; /* Init error flag */

#ifndef FIXED_POINT

    real_t scf;

#else

    int32_t sat_shift_mask = 0;

#endif

    k = 0;

    gindex = 0;

    /* In this case quant_to_spec is no-op and spec_data remains undefined.

     * Without peeking into AAC specification, there is no strong evidence if

     * such streams are invalid -> just calm down MSAN. */

    if (ics->num_swb == 0)

        memset(spec_data, 0, frame_len * sizeof(real_t));

    for (g = 0; g < ics->num_window_groups; g++)

    {

        uint16_t j = 0;

        uint16_t gincrease = 0;

        uint16_t win_inc = ics->swb_offset[ics->num_swb];

        for (sfb = 0; sfb < ics->num_swb; sfb++)

        {

            int32_t exp, frac;

            uint16_t wa = gindex + j;

            int16_t scale_factor = ics->scale_factors[g][sfb];

            width = ics->swb_offset[sfb+1] - ics->swb_offset[sfb];

#ifdef FIXED_POINT

            scale_factor -= 100;

            /* IMDCT pre-scaling */

            if (hDecoder->object_type == LD)

            {

                scale_factor -= 24 /*9*/;

            } else {

                if (ics->window_sequence == EIGHT_SHORT_SEQUENCE)

                    scale_factor -= 16 /*7*/;

                else

                    scale_factor -= 28 /*10*/;

            }

            if (scale_factor > 120)

                scale_factor = 120;  /* => exp <= 30 */

#else

            (void)hDecoder;

#endif

            /* scale_factor for IS or PNS, has different meaning; fill with almost zeroes */

            if (is_intensity(ics, g, sfb) || is_noise(ics, g, sfb))

            {

                scale_factor = 0;

            }

            /* scale_factor must be between 0 and 255 */

            exp = (scale_factor /* - 100 */) >> 2;

            /* frac must always be > 0 */

            frac = (scale_factor /* - 100 */) & 3;

#ifndef FIXED_POINT

            scf = pow2sf_tab[exp/*+25*/] * pow2_table[frac];

#else

            if (exp > 0)

                sat_shift_mask = SAT_SHIFT_MASK(exp);

#endif

            for (win = 0; win < ics->window_group_length[g]; win++)

            {

                for (bin = 0; bin < width; bin += 4)

                {

                    uint16_t wb = wa + bin;

#ifndef FIXED_POINT

                    spec_data[wb+0] = iquant(quant_data[k+0], tab, &error) * scf;

                    spec_data[wb+1] = iquant(quant_data[k+1], tab, &error) * scf;

                    spec_data[wb+2] = iquant(quant_data[k+2], tab, &error) * scf;

                    spec_data[wb+3] = iquant(quant_data[k+3], tab, &error) * scf;

#else

                    real_t iq0 = iquant(quant_data[k+0], tab, &error);

                    real_t iq1 = iquant(quant_data[k+1], tab, &error);

                    real_t iq2 = iquant(quant_data[k+2], tab, &error);

                    real_t iq3 = iquant(quant_data[k+3], tab, &error);

                    if (exp == -32)

                    {

                        spec_data[wb+0] = 0;

                        spec_data[wb+1] = 0;

                        spec_data[wb+2] = 0;

                        spec_data[wb+3] = 0;

                    } else if (exp <= 0) {

                        spec_data[wb+0] = iq0 >> -exp;

                        spec_data[wb+1] = iq1 >> -exp;

                        spec_data[wb+2] = iq2 >> -exp;

                        spec_data[wb+3] = iq3 >> -exp;

                    } else { /* exp > 0 */

                        spec_data[wb+0] = SAT_SHIFT(iq0, exp, sat_shift_mask);

                        spec_data[wb+1] = SAT_SHIFT(iq1, exp, sat_shift_mask);

                        spec_data[wb+2] = SAT_SHIFT(iq2, exp, sat_shift_mask);

                        spec_data[wb+3] = SAT_SHIFT(iq3, exp, sat_shift_mask);

                    }

                    if (frac != 0)

                    {

                        spec_data[wb+0] = MUL_C(spec_data[wb+0],pow2_table[frac]);

                        spec_data[wb+1] = MUL_C(spec_data[wb+1],pow2_table[frac]);

                        spec_data[wb+2] = MUL_C(spec_data[wb+2],pow2_table[frac]);

                        spec_data[wb+3] = MUL_C(spec_data[wb+3],pow2_table[frac]);

                    }

//#define SCFS_PRINT

#ifdef SCFS_PRINT

                    printf("%d\n", spec_data[gindex+(win*win_inc)+j+bin+0]);

                    printf("%d\n", spec_data[gindex+(win*win_inc)+j+bin+1]);

                    printf("%d\n", spec_data[gindex+(win*win_inc)+j+bin+2]);

                    printf("%d\n", spec_data[gindex+(win*win_inc)+j+bin+3]);

                    //printf("0x%.8X\n", spec_data[gindex+(win*win_inc)+j+bin+0]);

                    //printf("0x%.8X\n", spec_data[gindex+(win*win_inc)+j+bin+1]);

                    //printf("0x%.8X\n", spec_data[gindex+(win*win_inc)+j+bin+2]);

                    //printf("0x%.8X\n", spec_data[gindex+(win*win_inc)+j+bin+3]);

#endif

#endif

                    gincrease += 4;

                    k += 4;

                }

                wa += win_inc;

            }

            j += width;

        }

        gindex += gincrease;

    }

    return error;

}

static uint8_t allocate_single_channel(NeAACDecStruct *hDecoder, uint8_t channel,

                                       uint8_t output_channels)

{

    int mul = 1;

#ifdef MAIN_DEC

    /* MAIN object type prediction */

    if (hDecoder->object_type == MAIN)

    {

        /* allocate the state only when needed */

        if (hDecoder->pred_stat[channel] != NULL)

        {

            faad_free(hDecoder->pred_stat[channel]);

            hDecoder->pred_stat[channel] = NULL;

        }

        hDecoder->pred_stat[channel] = (pred_state*)faad_malloc(hDecoder->frameLength * sizeof(pred_state));

        reset_all_predictors(hDecoder->pred_stat[channel], hDecoder->frameLength);

    }

#endif

#ifdef LTP_DEC

    if (is_ltp_ot(hDecoder->object_type))

    {

        /* allocate the state only when needed */

        if (hDecoder->lt_pred_stat[channel] != NULL)

        {

            faad_free(hDecoder->lt_pred_stat[channel]);

            hDecoder->lt_pred_stat[channel] = NULL;

        }

        hDecoder->lt_pred_stat[channel] = (int16_t*)faad_malloc(hDecoder->frameLength*4 * sizeof(int16_t));

        memset(hDecoder->lt_pred_stat[channel], 0, hDecoder->frameLength*4 * sizeof(int16_t));

    }

#endif

    if (hDecoder->time_out[channel] != NULL)

    {

        faad_free(hDecoder->time_out[channel]);

        hDecoder->time_out[channel] = NULL;

    }

    {

        mul = 1;

#ifdef SBR_DEC

        hDecoder->sbr_alloced[hDecoder->fr_ch_ele] = 0;

        if ((hDecoder->sbr_present_flag == 1) || (hDecoder->forceUpSampling == 1))

        {

            /* SBR requires 2 times as much output data */

            mul = 2;

            hDecoder->sbr_alloced[hDecoder->fr_ch_ele] = 1;

        }

#endif

        hDecoder->time_out[channel] = (real_t*)faad_malloc(mul*hDecoder->frameLength*sizeof(real_t));

        memset(hDecoder->time_out[channel], 0, mul*hDecoder->frameLength*sizeof(real_t));

    }

#if (defined(PS_DEC) || defined(DRM_PS))

    if (output_channels == 2)

    {

        if (hDecoder->time_out[channel+1] != NULL)

        {

            faad_free(hDecoder->time_out[channel+1]);

            hDecoder->time_out[channel+1] = NULL;

        }

        hDecoder->time_out[channel+1] = (real_t*)faad_malloc(mul*hDecoder->frameLength*sizeof(real_t));

        memset(hDecoder->time_out[channel+1], 0, mul*hDecoder->frameLength*sizeof(real_t));

    }

#endif

    if (hDecoder->fb_intermed[channel] != NULL)

    {

        faad_free(hDecoder->fb_intermed[channel]);

        hDecoder->fb_intermed[channel] = NULL;

    }

    hDecoder->fb_intermed[channel] = (real_t*)faad_malloc(hDecoder->frameLength*sizeof(real_t));

    memset(hDecoder->fb_intermed[channel], 0, hDecoder->frameLength*sizeof(real_t));

#ifdef SSR_DEC

    if (hDecoder->object_type == SSR)

    {

        if (hDecoder->ssr_overlap[channel] == NULL)

        {

            hDecoder->ssr_overlap[channel] = (real_t*)faad_malloc(2*hDecoder->frameLength*sizeof(real_t));

            memset(hDecoder->ssr_overlap[channel], 0, 2*hDecoder->frameLength*sizeof(real_t));

        }

        if (hDecoder->prev_fmd[channel] == NULL)

        {

            uint16_t k;

            hDecoder->prev_fmd[channel] = (real_t*)faad_malloc(2*hDecoder->frameLength*sizeof(real_t));

            for (k = 0; k < 2*hDecoder->frameLength; k++)

                hDecoder->prev_fmd[channel][k] = REAL_CONST(-1);

        }

    }

#endif

    return 0;

}

static uint8_t allocate_channel_pair(NeAACDecStruct *hDecoder,

                                     uint8_t channel, uint8_t paired_channel)

{

    int mul = 1;

#ifdef MAIN_DEC

    /* MAIN object type prediction */

    if (hDecoder->object_type == MAIN)

    {

        /* allocate the state only when needed */

        if (hDecoder->pred_stat[channel] == NULL)

        {

            hDecoder->pred_stat[channel] = (pred_state*)faad_malloc(hDecoder->frameLength * sizeof(pred_state));

            reset_all_predictors(hDecoder->pred_stat[channel], hDecoder->frameLength);

        }

        if (hDecoder->pred_stat[paired_channel] == NULL)

        {

            hDecoder->pred_stat[paired_channel] = (pred_state*)faad_malloc(hDecoder->frameLength * sizeof(pred_state));

            reset_all_predictors(hDecoder->pred_stat[paired_channel], hDecoder->frameLength);

        }

    }

#endif

#ifdef LTP_DEC

    if (is_ltp_ot(hDecoder->object_type))

    {

        /* allocate the state only when needed */

        if (hDecoder->lt_pred_stat[channel] == NULL)

        {

            hDecoder->lt_pred_stat[channel] = (int16_t*)faad_malloc(hDecoder->frameLength*4 * sizeof(int16_t));

            memset(hDecoder->lt_pred_stat[channel], 0, hDecoder->frameLength*4 * sizeof(int16_t));

        }

        if (hDecoder->lt_pred_stat[paired_channel] == NULL)

        {

            hDecoder->lt_pred_stat[paired_channel] = (int16_t*)faad_malloc(hDecoder->frameLength*4 * sizeof(int16_t));

            memset(hDecoder->lt_pred_stat[paired_channel], 0, hDecoder->frameLength*4 * sizeof(int16_t));

        }

    }

#endif

    {

        mul = 1;

#ifdef SBR_DEC

        hDecoder->sbr_alloced[hDecoder->fr_ch_ele] = 0;

        if ((hDecoder->sbr_present_flag == 1) || (hDecoder->forceUpSampling == 1))

        {

            /* SBR requires 2 times as much output data */

            mul = 2;

            hDecoder->sbr_alloced[hDecoder->fr_ch_ele] = 1;

        }

#endif

    }

    if (hDecoder->time_out[channel] == NULL)

    {

        hDecoder->time_out[channel] = (real_t*)faad_malloc(mul*hDecoder->frameLength*sizeof(real_t));

        memset(hDecoder->time_out[channel], 0, mul*hDecoder->frameLength*sizeof(real_t));

    }

    if (hDecoder->time_out[paired_channel] == NULL)

    {

        hDecoder->time_out[paired_channel] = (real_t*)faad_malloc(mul*hDecoder->frameLength*sizeof(real_t));

        memset(hDecoder->time_out[paired_channel], 0, mul*hDecoder->frameLength*sizeof(real_t));

    }

    if (hDecoder->fb_intermed[channel] == NULL)

    {

        hDecoder->fb_intermed[channel] = (real_t*)faad_malloc(hDecoder->frameLength*sizeof(real_t));

        memset(hDecoder->fb_intermed[channel], 0, hDecoder->frameLength*sizeof(real_t));

    }

    if (hDecoder->fb_intermed[paired_channel] == NULL)

    {

        hDecoder->fb_intermed[paired_channel] = (real_t*)faad_malloc(hDecoder->frameLength*sizeof(real_t));

        memset(hDecoder->fb_intermed[paired_channel], 0, hDecoder->frameLength*sizeof(real_t));

    }

#ifdef SSR_DEC

    if (hDecoder->object_type == SSR)

    {

        if (hDecoder->ssr_overlap[cpe->channel] == NULL)

        {

            hDecoder->ssr_overlap[cpe->channel] = (real_t*)faad_malloc(2*hDecoder->frameLength*sizeof(real_t));

            memset(hDecoder->ssr_overlap[cpe->channel], 0, 2*hDecoder->frameLength*sizeof(real_t));

        }

        if (hDecoder->ssr_overlap[cpe->paired_channel] == NULL)

        {

            hDecoder->ssr_overlap[cpe->paired_channel] = (real_t*)faad_malloc(2*hDecoder->frameLength*sizeof(real_t));

            memset(hDecoder->ssr_overlap[cpe->paired_channel], 0, 2*hDecoder->frameLength*sizeof(real_t));

        }

        if (hDecoder->prev_fmd[cpe->channel] == NULL)

        {

            uint16_t k;

            hDecoder->prev_fmd[cpe->channel] = (real_t*)faad_malloc(2*hDecoder->frameLength*sizeof(real_t));

            for (k = 0; k < 2*hDecoder->frameLength; k++)

                hDecoder->prev_fmd[cpe->channel][k] = REAL_CONST(-1);

        }

        if (hDecoder->prev_fmd[cpe->paired_channel] == NULL)

        {

            uint16_t k;

            hDecoder->prev_fmd[cpe->paired_channel] = (real_t*)faad_malloc(2*hDecoder->frameLength*sizeof(real_t));

            for (k = 0; k < 2*hDecoder->frameLength; k++)

                hDecoder->prev_fmd[cpe->paired_channel][k] = REAL_CONST(-1);

        }

    }

#endif

    return 0;

}

uint8_t reconstruct_single_channel(NeAACDecStruct *hDecoder, ic_stream *ics,

                                   element *sce, int16_t *spec_data)

{

    uint8_t retval;

    uint8_t output_channels;

    ALIGN real_t spec_coef[1024];

#ifdef PROFILE

    int64_t count = faad_get_ts();

#endif

    /* always allocate 2 channels, PS can always "suddenly" turn up */

#if ( (defined(DRM) && defined(DRM_PS)) )

    output_channels = 2;

#elif defined(PS_DEC)

    if (hDecoder->ps_used[hDecoder->fr_ch_ele])

        output_channels = 2;

    else

        output_channels = 1;

#else

    output_channels = 1;

#endif

    if (hDecoder->element_output_channels[hDecoder->fr_ch_ele] == 0)

    {

        /* element_output_channels not set yet */

        hDecoder->element_output_channels[hDecoder->fr_ch_ele] = output_channels;

    } else if (hDecoder->element_output_channels[hDecoder->fr_ch_ele] != output_channels) {

        /* element inconsistency */

        /* this only happens if PS is actually found but not in the first frame

         * this means that there is only 1 bitstream element!

         */

        /* The simplest way to fix the accounting,

         * is to reallocate this and all the following channels.

         */

        memset(&hDecoder->element_alloced[hDecoder->fr_ch_ele], 0,

            sizeof(uint8_t) * (MAX_SYNTAX_ELEMENTS - hDecoder->fr_ch_ele));

        hDecoder->element_output_channels[hDecoder->fr_ch_ele] = output_channels;

        //return 21;

    }

    if (hDecoder->element_alloced[hDecoder->fr_ch_ele] == 0)

    {

        retval = allocate_single_channel(hDecoder, sce->channel, output_channels);

        if (retval > 0)

            return retval;

        hDecoder->element_alloced[hDecoder->fr_ch_ele] = 1;

    }

    /* sanity check, CVE-2018-20199, CVE-2018-20360 */

    if(!hDecoder->time_out[sce->channel])

        return 15;

    if(output_channels > 1 && !hDecoder->time_out[sce->channel+1])

        return 15;

    if(!hDecoder->fb_intermed[sce->channel])

        return 15;

    /* dequantisation and scaling */

    retval = quant_to_spec(hDecoder, ics, spec_data, spec_coef, hDecoder->frameLength);

    if (retval > 0)

        return retval;

#ifdef PROFILE

    count = faad_get_ts() - count;

    hDecoder->requant_cycles += count;

#endif

    /* pns decoding */

    pns_decode(ics, NULL, spec_coef, NULL, hDecoder->frameLength, 0, hDecoder->object_type,

        &(hDecoder->__r1), &(hDecoder->__r2));

#ifdef MAIN_DEC

    /* MAIN object type prediction */

    if (hDecoder->object_type == MAIN)

    {

    if (!hDecoder->pred_stat[sce->channel])

      return 33;

        /* intra channel prediction */

        ic_prediction(ics, spec_coef, hDecoder->pred_stat[sce->channel], hDecoder->frameLength,

            hDecoder->sf_index);

        /* In addition, for scalefactor bands coded by perceptual

           noise substitution the predictors belonging to the

           corresponding spectral coefficients are reset.

        */

        pns_reset_pred_state(ics, hDecoder->pred_stat[sce->channel]);

    }

#endif

#ifdef LTP_DEC

    if (is_ltp_ot(hDecoder->object_type))

    {

#ifdef LD_DEC

        if (hDecoder->object_type == LD)

        {

            if (ics->ltp.data_present)

            {

                if (ics->ltp.lag_update)

                    hDecoder->ltp_lag[sce->channel] = ics->ltp.lag;

            }

            ics->ltp.lag = hDecoder->ltp_lag[sce->channel];

        }

#endif

        /* long term prediction */

        lt_prediction(ics, &(ics->ltp), spec_coef, hDecoder->lt_pred_stat[sce->channel], hDecoder->fb,

            ics->window_shape, hDecoder->window_shape_prev[sce->channel],

            hDecoder->sf_index, hDecoder->object_type, hDecoder->frameLength);

    }

#endif

    /* tns decoding */

    tns_decode_frame(ics, &(ics->tns), hDecoder->sf_index, hDecoder->object_type,

        spec_coef, hDecoder->frameLength);

    /* drc decoding */

#ifdef APPLY_DRC

    if (hDecoder->drc->present)

    {

        if (!hDecoder->drc->exclude_mask[sce->channel] || !hDecoder->drc->excluded_chns_present)

            drc_decode(hDecoder->drc, spec_coef);

    }

#endif

    /* filter bank */

#ifdef SSR_DEC

    if (hDecoder->object_type != SSR)

    {

#endif

        ifilter_bank(hDecoder->fb, ics->window_sequence, ics->window_shape,

            hDecoder->window_shape_prev[sce->channel], spec_coef,

            hDecoder->time_out[sce->channel], hDecoder->fb_intermed[sce->channel],

            hDecoder->object_type, hDecoder->frameLength);

#ifdef SSR_DEC

    } else {

        ssr_decode(&(ics->ssr), hDecoder->fb, ics->window_sequence, ics->window_shape,

            hDecoder->window_shape_prev[sce->channel], spec_coef, hDecoder->time_out[sce->channel],

            hDecoder->ssr_overlap[sce->channel], hDecoder->ipqf_buffer[sce->channel], hDecoder->prev_fmd[sce->channel],

            hDecoder->frameLength);

    }

#endif

    /* save window shape for next frame */

    hDecoder->window_shape_prev[sce->channel] = ics->window_shape;

#ifdef LTP_DEC

    if (is_ltp_ot(hDecoder->object_type))

    {

        lt_update_state(hDecoder->lt_pred_stat[sce->channel], hDecoder->time_out[sce->channel],

            hDecoder->fb_intermed[sce->channel], hDecoder->frameLength, hDecoder->object_type);

    }

#endif

#ifdef SBR_DEC

    if (((hDecoder->sbr_present_flag == 1) || (hDecoder->forceUpSampling == 1))

        && hDecoder->sbr_alloced[hDecoder->fr_ch_ele])

    {

        int ele = hDecoder->fr_ch_ele;

        int ch = sce->channel;

        /* following case can happen when forceUpSampling == 1 */

        if (hDecoder->sbr[ele] == NULL)

        {

            hDecoder->sbr[ele] = sbrDecodeInit(hDecoder->frameLength,

                hDecoder->element_id[ele], 2*get_sample_rate(hDecoder->sf_index),

                hDecoder->downSampledSBR

#ifdef DRM

                , 0

#endif