/*

** 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: syntax.c,v 1.93 2009/01/26 23:51:15 menno Exp $

**/

/*

   Reads the AAC bitstream as defined in 14496-3 (MPEG-4 Audio)

*/

#include "common.h"

#include "structs.h"

#include <stdlib.h>

#include <stdio.h>

#include "syntax.h"

#include "specrec.h"

#include "huffman.h"

#include "bits.h"

#include "pulse.h"

#include "analysis.h"

#include "drc.h"

#ifdef ERROR_RESILIENCE

#include "rvlc.h"

#endif

#ifdef SBR_DEC

#include "sbr_syntax.h"

#endif

#include "mp4.h"

/* static function declarations */

static void decode_sce_lfe(NeAACDecStruct *hDecoder, NeAACDecFrameInfo *hInfo, bitfile *ld,

                           uint8_t id_syn_ele);

static void decode_cpe(NeAACDecStruct *hDecoder, NeAACDecFrameInfo *hInfo, bitfile *ld,

                       uint8_t id_syn_ele);

static uint8_t single_lfe_channel_element(NeAACDecStruct *hDecoder, bitfile *ld,

                                          uint8_t channel, uint8_t *tag);

static uint8_t channel_pair_element(NeAACDecStruct *hDecoder, bitfile *ld,

                                    uint8_t channel, uint8_t *tag);

#ifdef COUPLING_DEC

static uint8_t coupling_channel_element(NeAACDecStruct *hDecoder, bitfile *ld);

#endif

static uint16_t data_stream_element(NeAACDecStruct *hDecoder, bitfile *ld);

static uint8_t program_config_element(program_config *pce, bitfile *ld);

static uint8_t fill_element(NeAACDecStruct *hDecoder, bitfile *ld, drc_info *drc

#ifdef SBR_DEC

                            ,uint8_t sbr_ele

#endif

                            );

static uint8_t individual_channel_stream(NeAACDecStruct *hDecoder, element *ele,

                                         bitfile *ld, ic_stream *ics, uint8_t scal_flag,

                                         int16_t *spec_data);

static uint8_t ics_info(NeAACDecStruct *hDecoder, ic_stream *ics, bitfile *ld,

                        uint8_t common_window);

static uint8_t section_data(NeAACDecStruct *hDecoder, ic_stream *ics, bitfile *ld);

static uint8_t scale_factor_data(NeAACDecStruct *hDecoder, ic_stream *ics, bitfile *ld);

#ifdef SSR_DEC

static void gain_control_data(bitfile *ld, ic_stream *ics);

#endif

static uint8_t spectral_data(NeAACDecStruct *hDecoder, ic_stream *ics, bitfile *ld,

                             int16_t *spectral_data);

static uint8_t pulse_data(ic_stream *ics, pulse_info *pul, bitfile *ld);

static void tns_data(ic_stream *ics, tns_info *tns, bitfile *ld);

#ifdef LTP_DEC

static uint8_t ltp_data(NeAACDecStruct *hDecoder, ic_stream *ics, ltp_info *ltp, bitfile *ld);

#endif

static uint8_t adts_fixed_header(adts_header *adts, bitfile *ld);

static void adts_variable_header(adts_header *adts, bitfile *ld);

static void adts_error_check(adts_header *adts, bitfile *ld);

static uint8_t side_info(NeAACDecStruct *hDecoder, element *ele,

                         bitfile *ld, ic_stream *ics, uint8_t scal_flag);

#ifdef DRM

static int8_t DRM_aac_scalable_main_header(NeAACDecStruct *hDecoder, ic_stream *ics1, ic_stream *ics2,

                                           bitfile *ld, uint8_t this_layer_stereo);

#else

static uint16_t extension_payload(bitfile *ld, drc_info *drc, uint16_t count);

static uint8_t dynamic_range_info(bitfile *ld, drc_info *drc);

static uint8_t excluded_channels(bitfile *ld, drc_info *drc);

#endif

/* Table 4.4.1 */

int8_t GASpecificConfig(bitfile *ld, mp4AudioSpecificConfig *mp4ASC,

                        program_config *pce_out)

{

    program_config pce;

    /* 1024 or 960 */

    mp4ASC->frameLengthFlag = faad_get1bit(ld

        DEBUGVAR(1,138,"GASpecificConfig(): FrameLengthFlag"));

#ifndef ALLOW_SMALL_FRAMELENGTH

    if (mp4ASC->frameLengthFlag == 1)

        return -3;

#endif

    mp4ASC->dependsOnCoreCoder = faad_get1bit(ld

        DEBUGVAR(1,139,"GASpecificConfig(): DependsOnCoreCoder"));

    if (mp4ASC->dependsOnCoreCoder == 1)

    {

        mp4ASC->coreCoderDelay = (uint16_t)faad_getbits(ld, 14

            DEBUGVAR(1,140,"GASpecificConfig(): CoreCoderDelay"));

    }

    mp4ASC->extensionFlag = faad_get1bit(ld DEBUGVAR(1,141,"GASpecificConfig(): ExtensionFlag"));

    if (mp4ASC->channelsConfiguration == 0)

    {

        if (program_config_element(&pce, ld))

            return -3;

        //mp4ASC->channelsConfiguration = pce.channels;

        if (pce_out != NULL)

            memcpy(pce_out, &pce, sizeof(program_config));

        /*

        if (pce.num_valid_cc_elements)

            return -3;

        */

    }

#ifdef ERROR_RESILIENCE

    if (mp4ASC->extensionFlag == 1)

    {

        /* Error resilience not supported yet */

        if (mp4ASC->objectTypeIndex >= ER_OBJECT_START)

        {

            mp4ASC->aacSectionDataResilienceFlag = faad_get1bit(ld

                DEBUGVAR(1,144,"GASpecificConfig(): aacSectionDataResilienceFlag"));

            mp4ASC->aacScalefactorDataResilienceFlag = faad_get1bit(ld

                DEBUGVAR(1,145,"GASpecificConfig(): aacScalefactorDataResilienceFlag"));

            mp4ASC->aacSpectralDataResilienceFlag = faad_get1bit(ld

                DEBUGVAR(1,146,"GASpecificConfig(): aacSpectralDataResilienceFlag"));

        }

        /* 1 bit: extensionFlag3 */

        faad_getbits(ld, 1);

  }

#endif

    return 0;

}

/* Table 4.4.2 */

/* An MPEG-4 Audio decoder is only required to follow the Program

   Configuration Element in GASpecificConfig(). The decoder shall ignore

   any Program Configuration Elements that may occur in raw data blocks.

   PCEs transmitted in raw data blocks cannot be used to convey decoder

   configuration information.

*/

static uint8_t program_config_element(program_config *pce, bitfile *ld)

{

    uint8_t i;

    memset(pce, 0, sizeof(program_config));

    pce->channels = 0;

    pce->element_instance_tag = (uint8_t)faad_getbits(ld, 4

        DEBUGVAR(1,10,"program_config_element(): element_instance_tag"));

    pce->object_type = (uint8_t)faad_getbits(ld, 2

        DEBUGVAR(1,11,"program_config_element(): object_type"));

    pce->sf_index = (uint8_t)faad_getbits(ld, 4

        DEBUGVAR(1,12,"program_config_element(): sf_index"));

    pce->num_front_channel_elements = (uint8_t)faad_getbits(ld, 4

        DEBUGVAR(1,13,"program_config_element(): num_front_channel_elements"));

    pce->num_side_channel_elements = (uint8_t)faad_getbits(ld, 4

        DEBUGVAR(1,14,"program_config_element(): num_side_channel_elements"));

    pce->num_back_channel_elements = (uint8_t)faad_getbits(ld, 4

        DEBUGVAR(1,15,"program_config_element(): num_back_channel_elements"));

    pce->num_lfe_channel_elements = (uint8_t)faad_getbits(ld, 2

        DEBUGVAR(1,16,"program_config_element(): num_lfe_channel_elements"));

    pce->num_assoc_data_elements = (uint8_t)faad_getbits(ld, 3

        DEBUGVAR(1,17,"program_config_element(): num_assoc_data_elements"));

    pce->num_valid_cc_elements = (uint8_t)faad_getbits(ld, 4

        DEBUGVAR(1,18,"program_config_element(): num_valid_cc_elements"));

    pce->mono_mixdown_present = faad_get1bit(ld

        DEBUGVAR(1,19,"program_config_element(): mono_mixdown_present"));

    if (pce->mono_mixdown_present == 1)

    {

        pce->mono_mixdown_element_number = (uint8_t)faad_getbits(ld, 4

            DEBUGVAR(1,20,"program_config_element(): mono_mixdown_element_number"));

    }

    pce->stereo_mixdown_present = faad_get1bit(ld

        DEBUGVAR(1,21,"program_config_element(): stereo_mixdown_present"));

    if (pce->stereo_mixdown_present == 1)

    {

        pce->stereo_mixdown_element_number = (uint8_t)faad_getbits(ld, 4

            DEBUGVAR(1,22,"program_config_element(): stereo_mixdown_element_number"));

    }

    pce->matrix_mixdown_idx_present = faad_get1bit(ld

        DEBUGVAR(1,23,"program_config_element(): matrix_mixdown_idx_present"));

    if (pce->matrix_mixdown_idx_present == 1)

    {

        pce->matrix_mixdown_idx = (uint8_t)faad_getbits(ld, 2

            DEBUGVAR(1,24,"program_config_element(): matrix_mixdown_idx"));

        pce->pseudo_surround_enable = faad_get1bit(ld

            DEBUGVAR(1,25,"program_config_element(): pseudo_surround_enable"));

    }

    for (i = 0; i < pce->num_front_channel_elements; i++)

    {

        pce->front_element_is_cpe[i] = faad_get1bit(ld

            DEBUGVAR(1,26,"program_config_element(): front_element_is_cpe"));

        pce->front_element_tag_select[i] = (uint8_t)faad_getbits(ld, 4

            DEBUGVAR(1,27,"program_config_element(): front_element_tag_select"));

        if (pce->front_element_is_cpe[i] & 1)

        {

            pce->cpe_channel[pce->front_element_tag_select[i]] = pce->channels;

            pce->num_front_channels += 2;

            pce->channels += 2;

        } else {

            pce->sce_channel[pce->front_element_tag_select[i]] = pce->channels;

            pce->num_front_channels++;

            pce->channels++;

        }

    }

    for (i = 0; i < pce->num_side_channel_elements; i++)

    {

        pce->side_element_is_cpe[i] = faad_get1bit(ld

            DEBUGVAR(1,28,"program_config_element(): side_element_is_cpe"));

        pce->side_element_tag_select[i] = (uint8_t)faad_getbits(ld, 4

            DEBUGVAR(1,29,"program_config_element(): side_element_tag_select"));

        if (pce->side_element_is_cpe[i] & 1)

        {

            pce->cpe_channel[pce->side_element_tag_select[i]] = pce->channels;

            pce->num_side_channels += 2;

            pce->channels += 2;

        } else {

            pce->sce_channel[pce->side_element_tag_select[i]] = pce->channels;

            pce->num_side_channels++;

            pce->channels++;

        }

    }

    for (i = 0; i < pce->num_back_channel_elements; i++)

    {

        pce->back_element_is_cpe[i] = faad_get1bit(ld

            DEBUGVAR(1,30,"program_config_element(): back_element_is_cpe"));

        pce->back_element_tag_select[i] = (uint8_t)faad_getbits(ld, 4

            DEBUGVAR(1,31,"program_config_element(): back_element_tag_select"));

        if (pce->back_element_is_cpe[i] & 1)

        {

            pce->cpe_channel[pce->back_element_tag_select[i]] = pce->channels;

            pce->channels += 2;

            pce->num_back_channels += 2;

        } else {

            pce->sce_channel[pce->back_element_tag_select[i]] = pce->channels;

            pce->num_back_channels++;

            pce->channels++;

        }

    }

    for (i = 0; i < pce->num_lfe_channel_elements; i++)

    {

        pce->lfe_element_tag_select[i] = (uint8_t)faad_getbits(ld, 4

            DEBUGVAR(1,32,"program_config_element(): lfe_element_tag_select"));

        pce->sce_channel[pce->lfe_element_tag_select[i]] = pce->channels;

        pce->num_lfe_channels++;

        pce->channels++;

    }

    for (i = 0; i < pce->num_assoc_data_elements; i++)

        pce->assoc_data_element_tag_select[i] = (uint8_t)faad_getbits(ld, 4

        DEBUGVAR(1,33,"program_config_element(): assoc_data_element_tag_select"));

    for (i = 0; i < pce->num_valid_cc_elements; i++)

    {

        pce->cc_element_is_ind_sw[i] = faad_get1bit(ld

            DEBUGVAR(1,34,"program_config_element(): cc_element_is_ind_sw"));

        pce->valid_cc_element_tag_select[i] = (uint8_t)faad_getbits(ld, 4

            DEBUGVAR(1,35,"program_config_element(): valid_cc_element_tag_select"));

    }

    faad_byte_align(ld);

    pce->comment_field_bytes = (uint8_t)faad_getbits(ld, 8

        DEBUGVAR(1,36,"program_config_element(): comment_field_bytes"));

    for (i = 0; i < pce->comment_field_bytes; i++)

    {

        pce->comment_field_data[i] = (uint8_t)faad_getbits(ld, 8

            DEBUGVAR(1,37,"program_config_element(): comment_field_data"));

    }

    pce->comment_field_data[i] = 0;

    if (pce->channels > MAX_CHANNELS)

        return 22;

    return 0;

}

static void decode_sce_lfe(NeAACDecStruct *hDecoder,

                           NeAACDecFrameInfo *hInfo, bitfile *ld,

                           uint8_t id_syn_ele)

{

    uint8_t channels = hDecoder->fr_channels;

    uint8_t tag = 0;

    /* One or two channels are used;

       exact number will be known after single_lfe_channel_element

    */

    if (channels+2 > MAX_CHANNELS)

    {

        hInfo->error = 12;

        return;

    }

    if (hDecoder->fr_ch_ele+1 > MAX_SYNTAX_ELEMENTS)

    {

        hInfo->error = 13;

        return;

    }

    /* for SCE hDecoder->element_output_channels[] is not set here because this

       can become 2 when some form of Parametric Stereo coding is used

    */

    if (hDecoder->element_id[hDecoder->fr_ch_ele] != INVALID_ELEMENT_ID &&

        hDecoder->element_id[hDecoder->fr_ch_ele] != id_syn_ele)

    {

        /* element inconsistency */

        hInfo->error = 21;

        return;

    }

    /* save the syntax element id */

    hDecoder->element_id[hDecoder->fr_ch_ele] = id_syn_ele;

    /* decode the element */

    hInfo->error = single_lfe_channel_element(hDecoder, ld, channels, &tag);

    /* map output channels position to internal data channels */

    if (hDecoder->element_output_channels[hDecoder->fr_ch_ele] == 2)

    {

        /* this might be faulty when pce_set is true */

        hDecoder->internal_channel[channels] = channels;

        hDecoder->internal_channel[channels+1] = channels+1;

    } else {

        if (hDecoder->pce_set)

        {

            if (hDecoder->pce.channels > MAX_CHANNELS)

            {

                hInfo->error = 22;

                return;

            }

            hDecoder->internal_channel[hDecoder->pce.sce_channel[tag]] = channels;

        } else {

            hDecoder->internal_channel[channels] = channels;

        }

    }

    hDecoder->fr_channels += hDecoder->element_output_channels[hDecoder->fr_ch_ele];

    hDecoder->fr_ch_ele++;

}

static void decode_cpe(NeAACDecStruct *hDecoder, NeAACDecFrameInfo *hInfo, bitfile *ld,

                       uint8_t id_syn_ele)

{

    uint8_t channels = hDecoder->fr_channels;

    uint8_t tag = 0;

    if (channels+2 > MAX_CHANNELS)

    {

        hInfo->error = 12;

        return;

    }

    if (hDecoder->fr_ch_ele+1 > MAX_SYNTAX_ELEMENTS)

    {

        hInfo->error = 13;

        return;

    }

    if (hDecoder->pce_set && (hDecoder->pce.channels > MAX_CHANNELS))

    {

        hInfo->error = 22;

        return;

    }

    /* for CPE the number of output channels is always 2 */

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

    {

        /* element_output_channels not set yet */

        hDecoder->element_output_channels[hDecoder->fr_ch_ele] = 2;

    } else if (hDecoder->element_output_channels[hDecoder->fr_ch_ele] != 2) {

        /* element inconsistency */

        hInfo->error = 21;

        return;

    }

    if (hDecoder->element_id[hDecoder->fr_ch_ele] != INVALID_ELEMENT_ID &&

        hDecoder->element_id[hDecoder->fr_ch_ele] != id_syn_ele)

    {

        /* element inconsistency */

        hInfo->error = 21;

        return;

    }

    /* save the syntax element id */

    hDecoder->element_id[hDecoder->fr_ch_ele] = id_syn_ele;

    /* decode the element */

    hInfo->error = channel_pair_element(hDecoder, ld, channels, &tag);

    /* map output channel position to internal data channels */

    if (hDecoder->pce_set)

    {

        hDecoder->internal_channel[hDecoder->pce.cpe_channel[tag]] = channels;

        hDecoder->internal_channel[hDecoder->pce.cpe_channel[tag]+1] = channels+1;

    } else {

        hDecoder->internal_channel[channels] = channels;

        hDecoder->internal_channel[channels+1] = channels+1;

    }

    hDecoder->fr_channels += 2;

    hDecoder->fr_ch_ele++;

}

void raw_data_block(NeAACDecStruct *hDecoder, NeAACDecFrameInfo *hInfo,

                    bitfile *ld, program_config *pce, drc_info *drc)

{

    uint8_t id_syn_ele;

    uint8_t ele_this_frame = 0;

    hDecoder->fr_channels = 0;

    hDecoder->fr_ch_ele = 0;

    hDecoder->first_syn_ele = 25;

    hDecoder->has_lfe = 0;

#ifdef ERROR_RESILIENCE

    if (hDecoder->object_type < ER_OBJECT_START)

    {

#endif

        /* Table 4.4.3: raw_data_block() */

        while ((id_syn_ele = (uint8_t)faad_getbits(ld, LEN_SE_ID

            DEBUGVAR(1,4,"NeAACDecDecode(): id_syn_ele"))) != ID_END)

        {

            switch (id_syn_ele) {

            case ID_SCE:

                ele_this_frame++;

                if (hDecoder->first_syn_ele == 25) hDecoder->first_syn_ele = id_syn_ele;

                decode_sce_lfe(hDecoder, hInfo, ld, id_syn_ele);

                if (hInfo->error > 0)

                    return;

                break;

            case ID_CPE:

                ele_this_frame++;

                if (hDecoder->first_syn_ele == 25) hDecoder->first_syn_ele = id_syn_ele;

                decode_cpe(hDecoder, hInfo, ld, id_syn_ele);

                if (hInfo->error > 0)

                    return;

                break;

            case ID_LFE:

#ifdef DRM

                hInfo->error = 32;

#else

                ele_this_frame++;

                hDecoder->has_lfe++;

                decode_sce_lfe(hDecoder, hInfo, ld, id_syn_ele);

#endif

                if (hInfo->error > 0)

                    return;

                break;

            case ID_CCE: /* not implemented yet, but skip the bits */

#ifdef DRM

                hInfo->error = 32;

#else

                ele_this_frame++;

#ifdef COUPLING_DEC

                hInfo->error = coupling_channel_element(hDecoder, ld);

#else

                hInfo->error = 6;

#endif

#endif

                if (hInfo->error > 0)

                    return;

                break;

            case ID_DSE:

                ele_this_frame++;

                data_stream_element(hDecoder, ld);

                break;

            case ID_PCE:

                if (ele_this_frame != 0)

                {

                    hInfo->error = 31;

                    return;

                }

                ele_this_frame++;

                /* 14496-4: 5.6.4.1.2.1.3: */

                /* program_configuration_element()'s in access units shall be ignored */

                program_config_element(pce, ld);

                //if ((hInfo->error = program_config_element(pce, ld)) > 0)

                //    return;

                //hDecoder->pce_set = 1;

                break;

            case ID_FIL:

                ele_this_frame++;

                /* one sbr_info describes a channel_element not a channel! */

                /* if we encounter SBR data here: error */

                /* SBR data will be read directly in the SCE/LFE/CPE element */

                if ((hInfo->error = fill_element(hDecoder, ld, drc

#ifdef SBR_DEC

                    , INVALID_SBR_ELEMENT

#endif

                    )) > 0)

                    return;

                break;

            }

            if (ld->error != 0)

            {

                hInfo->error = 32;

                return;

            }

        }

#ifdef ERROR_RESILIENCE

    } else {

        /* Table 262: er_raw_data_block() */

        switch (hDecoder->channelConfiguration)

        {

        case 1:

            decode_sce_lfe(hDecoder, hInfo, ld, ID_SCE);

            if (hInfo->error > 0)

                return;

            break;

        case 2:

            decode_cpe(hDecoder, hInfo, ld, ID_CPE);

            if (hInfo->error > 0)

                return;

            break;

        case 3:

            decode_sce_lfe(hDecoder, hInfo, ld, ID_SCE);

            if (hInfo->error > 0)

                return;

            decode_cpe(hDecoder, hInfo, ld, ID_CPE);

            if (hInfo->error > 0)

                return;

            break;

        case 4:

            decode_sce_lfe(hDecoder, hInfo, ld, ID_SCE);

            if (hInfo->error > 0)

                return;

            decode_cpe(hDecoder, hInfo, ld, ID_CPE);

            if (hInfo->error > 0)

                return;

            decode_sce_lfe(hDecoder, hInfo, ld, ID_SCE);

            if (hInfo->error > 0)

                return;

            break;

        case 5:

            decode_sce_lfe(hDecoder, hInfo, ld, ID_SCE);

            if (hInfo->error > 0)

                return;

            decode_cpe(hDecoder, hInfo, ld, ID_CPE);

            if (hInfo->error > 0)

                return;

            decode_cpe(hDecoder, hInfo, ld, ID_CPE);

            if (hInfo->error > 0)

                return;

            break;

        case 6:

            decode_sce_lfe(hDecoder, hInfo, ld, ID_SCE);

            if (hInfo->error > 0)

                return;

            decode_cpe(hDecoder, hInfo, ld, ID_CPE);

            if (hInfo->error > 0)

                return;

            decode_cpe(hDecoder, hInfo, ld, ID_CPE);

            if (hInfo->error > 0)

                return;

            decode_sce_lfe(hDecoder, hInfo, ld, ID_LFE);

            if (hInfo->error > 0)

                return;

            break;

        case 7: /* 8 channels */

            decode_sce_lfe(hDecoder, hInfo, ld, ID_SCE);

            if (hInfo->error > 0)

                return;

            decode_cpe(hDecoder, hInfo, ld, ID_CPE);

            if (hInfo->error > 0)

                return;

            decode_cpe(hDecoder, hInfo, ld, ID_CPE);

            if (hInfo->error > 0)

                return;

            decode_cpe(hDecoder, hInfo, ld, ID_CPE);

            if (hInfo->error > 0)

                return;

            decode_sce_lfe(hDecoder, hInfo, ld, ID_LFE);

            if (hInfo->error > 0)

                return;

            break;

        default:

            hInfo->error = 7;

            return;

        }

#if 0

        cnt = bits_to_decode() / 8;

        while (cnt >= 1)

        {

            cnt -= extension_payload(cnt);

        }

#endif

    }

#endif

    /* new in corrigendum 14496-3:2002 */

#ifdef DRM

    if (hDecoder->object_type != DRM_ER_LC

#if 0

        && !hDecoder->latm_header_present

#endif

        )

#endif

    {

        faad_byte_align(ld);

    }

    return;

}

/* Table 4.4.4 and */

/* Table 4.4.9 */

static uint8_t single_lfe_channel_element(NeAACDecStruct *hDecoder, bitfile *ld,

                                          uint8_t channel, uint8_t *tag)

{

    uint8_t retval = 0;

    element sce = {0};

    ic_stream *ics = &(sce.ics1);

    ALIGN int16_t spec_data[1024] = {0};

    sce.element_instance_tag = (uint8_t)faad_getbits(ld, LEN_TAG

        DEBUGVAR(1,38,"single_lfe_channel_element(): element_instance_tag"));

    *tag = sce.element_instance_tag;

    sce.channel = channel;

    sce.paired_channel = -1;

    retval = individual_channel_stream(hDecoder, &sce, ld, ics, 0, spec_data);

    if (retval > 0)

        return retval;

    /* IS not allowed in single channel */

    if (ics->is_used)

        return 32;

#ifdef SBR_DEC

    /* check if next bitstream element is a fill element */

    /* if so, read it now so SBR decoding can be done in case of a file with SBR */

    if (faad_showbits(ld, LEN_SE_ID) == ID_FIL)

    {

        faad_flushbits(ld, LEN_SE_ID);

        /* one sbr_info describes a channel_element not a channel! */

        if ((retval = fill_element(hDecoder, ld, hDecoder->drc, hDecoder->fr_ch_ele)) > 0)

        {

            return retval;

        }

    }

#endif

    /* noiseless coding is done, spectral reconstruction is done now */

    retval = reconstruct_single_channel(hDecoder, ics, &sce, spec_data);

    if (retval > 0)

        return retval;

    return 0;

}

/* Table 4.4.5 */

static uint8_t channel_pair_element(NeAACDecStruct *hDecoder, bitfile *ld,

                                    uint8_t channels, uint8_t *tag)

{

    ALIGN int16_t spec_data1[1024] = {0};

    ALIGN int16_t spec_data2[1024] = {0};

    element cpe = {0};

    ic_stream *ics1 = &(cpe.ics1);

    ic_stream *ics2 = &(cpe.ics2);

    uint8_t result;

    cpe.channel        = channels;

    cpe.paired_channel = channels+1;

    cpe.element_instance_tag = (uint8_t)faad_getbits(ld, LEN_TAG

        DEBUGVAR(1,39,"channel_pair_element(): element_instance_tag"));

    *tag = cpe.element_instance_tag;

    if ((cpe.common_window = faad_get1bit(ld

        DEBUGVAR(1,40,"channel_pair_element(): common_window"))) & 1)

    {

        /* both channels have common ics information */

        if ((result = ics_info(hDecoder, ics1, ld, cpe.common_window)) > 0)

            return result;

        ics1->ms_mask_present = (uint8_t)faad_getbits(ld, 2

            DEBUGVAR(1,41,"channel_pair_element(): ms_mask_present"));

        if (ics1->ms_mask_present == 3)

        {

            /* bitstream error */

            return 32;

        }

        if (ics1->ms_mask_present == 1)

        {

            uint8_t g, sfb;

            for (g = 0; g < ics1->num_window_groups; g++)

            {

                for (sfb = 0; sfb < ics1->max_sfb; sfb++)

                {

                    ics1->ms_used[g][sfb] = faad_get1bit(ld

                        DEBUGVAR(1,42,"channel_pair_element(): faad_get1bit"));

                }

            }

        }

#ifdef ERROR_RESILIENCE

        if ((hDecoder->object_type >= ER_OBJECT_START) && (ics1->predictor_data_present))

        {

            if ((

#ifdef LTP_DEC

                ics1->ltp.data_present =

#endif

                faad_get1bit(ld DEBUGVAR(1,50,"channel_pair_element(): ltp.data_present"))) & 1)

            {

#ifdef LTP_DEC

                if ((result = ltp_data(hDecoder, ics1, &(ics1->ltp), ld)) > 0)

                {

                    return result;

                }

#else

                return 26;

#endif

            }

        }

#endif

        memcpy(ics2, ics1, sizeof(ic_stream));

    } else {

        ics1->ms_mask_present = 0;

    }

    if ((result = individual_channel_stream(hDecoder, &cpe, ld, ics1,

        0, spec_data1)) > 0)

    {

        return result;

    }

#ifdef ERROR_RESILIENCE

    if (cpe.common_window && (hDecoder->object_type >= ER_OBJECT_START) &&

        (ics1->predictor_data_present))

    {

        if ((

#ifdef LTP_DEC

            ics1->ltp2.data_present =

#endif

            faad_get1bit(ld DEBUGVAR(1,50,"channel_pair_element(): ltp.data_present"))) & 1)

        {

#ifdef LTP_DEC

            if ((result = ltp_data(hDecoder, ics1, &(ics1->ltp2), ld)) > 0)

            {

                return result;

            }

#else

            return 26;

#endif

        }

    }

#endif

    if ((result = individual_channel_stream(hDecoder, &cpe, ld, ics2,

        0, spec_data2)) > 0)

    {

        return result;

    }

#ifdef SBR_DEC

    /* check if next bitstream element is a fill element */

    /* if so, read it now so SBR decoding can be done in case of a file with SBR */

    if (faad_showbits(ld, LEN_SE_ID) == ID_FIL)

    {

        faad_flushbits(ld, LEN_SE_ID);

        /* one sbr_info describes a channel_element not a channel! */

        if ((result = fill_element(hDecoder, ld, hDecoder->drc, hDecoder->fr_ch_ele)) > 0)

        {

            return result;

        }

    }

#endif

    /* noiseless coding is done, spectral reconstruction is done now */

    if ((result = reconstruct_channel_pair(hDecoder, ics1, ics2, &cpe,

        spec_data1, spec_data2)) > 0)

    {

        return result;

    }

    return 0;

}

/* Table 4.4.6 */

static uint8_t ics_info(NeAACDecStruct *hDecoder, ic_stream *ics, bitfile *ld,

                        uint8_t common_window)

{

    uint8_t retval = 0;

    uint8_t ics_reserved_bit;

    ics_reserved_bit = faad_get1bit(ld

        DEBUGVAR(1,43,"ics_info(): ics_reserved_bit"));

    if (ics_reserved_bit != 0)

        return 32;

    ics->window_sequence = (uint8_t)faad_getbits(ld, 2

        DEBUGVAR(1,44,"ics_info(): window_sequence"));

    ics->window_shape = faad_get1bit(ld

        DEBUGVAR(1,45,"ics_info(): window_shape"));

#ifdef LD_DEC

    /* No block switching in LD */

    if ((hDecoder->object_type == LD) && (ics->window_sequence != ONLY_LONG_SEQUENCE))

        return 32;

#endif

    if (ics->window_sequence == EIGHT_SHORT_SEQUENCE)

    {

        ics->max_sfb = (uint8_t)faad_getbits(ld, 4

            DEBUGVAR(1,46,"ics_info(): max_sfb (short)"));

        ics->scale_factor_grouping = (uint8_t)faad_getbits(ld, 7

            DEBUGVAR(1,47,"ics_info(): scale_factor_grouping"));

    } else {

        ics->max_sfb = (uint8_t)faad_getbits(ld, 6

            DEBUGVAR(1,48,"ics_info(): max_sfb (long)"));

    }

    /* get the grouping information */

    if ((retval = window_grouping_info(hDecoder, ics)) > 0)

        return retval;

    /* should be an error */

    /* check the range of max_sfb */

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

        return 16;

    if (ics->window_sequence != EIGHT_SHORT_SEQUENCE)

    {

        if ((ics->predictor_data_present = faad_get1bit(ld

            DEBUGVAR(1,49,"ics_info(): predictor_data_present"))) & 1)

        {

            if (hDecoder->object_type == MAIN) /* MPEG2 style AAC predictor */

            {

                uint8_t sfb;

                uint8_t predictor_reset, predictor_reset_group_number, prediction_used;

                uint8_t limit = min(ics->max_sfb, max_pred_sfb(hDecoder->sf_index));

                predictor_reset = faad_get1bit(ld DEBUGVAR(1,53,"ics_info(): pred.predictor_reset"));

                if (predictor_reset)

                {

                    predictor_reset_group_number =

                        (uint8_t)faad_getbits(ld, 5 DEBUGVAR(1,54,"ics_info(): pred.predictor_reset_group_number"));

                } else {

                    predictor_reset_group_number = 0;

                }

                for (sfb = 0; sfb < limit; sfb++)

                {

                    prediction_used = faad_get1bit(ld DEBUGVAR(1,55,"ics_info(): pred.prediction_used"));

#ifdef MAIN_DEC

                    ics->pred.prediction_used[sfb] = prediction_used;

#endif

                }

#ifdef MAIN_DEC

                ics->pred.limit = limit;

                ics->pred.predictor_reset = predictor_reset;

                ics->pred.predictor_reset_group_number = predictor_reset_group_number;

#else

                (void)predictor_reset_group_number;

                (void)prediction_used;

#endif

            }

#ifdef LTP_DEC

            else { /* Long Term Prediction */

                if (hDecoder->object_type < ER_OBJECT_START)

                {

                    if ((ics->ltp.data_present = faad_get1bit(ld

                        DEBUGVAR(1,50,"ics_info(): ltp.data_present"))) & 1)

                    {

                        if ((retval = ltp_data(hDecoder, ics, &(ics->ltp), ld)) > 0)

                        {

                            return retval;

                        }

                    }

                    if (common_window)

                    {

                        if ((ics->ltp2.data_present = faad_get1bit(ld

                            DEBUGVAR(1,51,"ics_info(): ltp2.data_present"))) & 1)

                        {

                            if ((retval = ltp_data(hDecoder, ics, &(ics->ltp2), ld)) > 0)

                            {

                                return retval;

                            }

                        }

                    }

                }

#ifdef ERROR_RESILIENCE

                if (!common_window && (hDecoder->object_type >= ER_OBJECT_START))

                {

                    if ((ics->ltp.data_present = faad_get1bit(ld

                        DEBUGVAR(1,50,"ics_info(): ltp.data_present"))) & 1)

                    {

                        if ((retval = ltp_data(hDecoder, ics, &(ics->ltp), ld)) > 0)

                        {

                            return retval;

                        }

                    }

                }

#endif  /* ERROR_RESILIENCE */

            }

#else  /* LTP_DEC */

            (void)common_window;

#endif  /* LTP_DEC */

        }

    }

    return retval;

}

/* Table 4.4.7 */

static uint8_t pulse_data(ic_stream *ics, pulse_info *pul, bitfile *ld)

{

    uint8_t i;

    pul->number_pulse = (uint8_t)faad_getbits(ld, 2

        DEBUGVAR(1,56,"pulse_data(): number_pulse"));

    pul->pulse_start_sfb = (uint8_t)faad_getbits(ld, 6

        DEBUGVAR(1,57,"pulse_data(): pulse_start_sfb"));

    /* check the range of pulse_start_sfb */

    if (pul->pulse_start_sfb > ics->num_swb)

        return 16;

    for (i = 0; i < pul->number_pulse+1; i++)

    {

        pul->pulse_offset[i] = (uint8_t)faad_getbits(ld, 5

            DEBUGVAR(1,58,"pulse_data(): pulse_offset"));

#if 0

        printf("%d\n", pul->pulse_offset[i]);

#endif

        pul->pulse_amp[i] = (uint8_t)faad_getbits(ld, 4

            DEBUGVAR(1,59,"pulse_data(): pulse_amp"));

#if 0

        printf("%d\n", pul->pulse_amp[i]);

#endif

    }

    return 0;

}

#ifdef COUPLING_DEC

/* Table 4.4.8: Currently just for skipping the bits... */

static uint8_t coupling_channel_element(NeAACDecStruct *hDecoder, bitfile *ld)

{

    uint8_t c, result = 0;

    uint8_t ind_sw_cce_flag = 0;

    uint8_t num_gain_element_lists = 0;

    uint8_t num_coupled_elements = 0;

    element el_empty = {0};

    ic_stream ics_empty = {0};

    int16_t sh_data[1024];

    c = faad_getbits(ld, LEN_TAG

        DEBUGVAR(1,900,"coupling_channel_element(): element_instance_tag"));

    ind_sw_cce_flag = faad_get1bit(ld

        DEBUGVAR(1,901,"coupling_channel_element(): ind_sw_cce_flag"));

    num_coupled_elements = faad_getbits(ld, 3

        DEBUGVAR(1,902,"coupling_channel_element(): num_coupled_elements"));

    for (c = 0; c < num_coupled_elements + 1; c++)

    {

        uint8_t cc_target_is_cpe, cc_target_tag_select;

        num_gain_element_lists++;

        cc_target_is_cpe = faad_get1bit(ld

            DEBUGVAR(1,903,"coupling_channel_element(): cc_target_is_cpe"));

        cc_target_tag_select = faad_getbits(ld, 4

            DEBUGVAR(1,904,"coupling_channel_element(): cc_target_tag_select"));

        if (cc_target_is_cpe)

        {

            uint8_t cc_l = faad_get1bit(ld

                DEBUGVAR(1,905,"coupling_channel_element(): cc_l"));

            uint8_t cc_r = faad_get1bit(ld

                DEBUGVAR(1,906,"coupling_channel_element(): cc_r"));

            if (cc_l && cc_r)

                num_gain_element_lists++;

        }

    }

    faad_get1bit(ld

        DEBUGVAR(1,907,"coupling_channel_element(): cc_domain"));

    faad_get1bit(ld

        DEBUGVAR(1,908,"coupling_channel_element(): gain_element_sign"));

    faad_getbits(ld, 2

        DEBUGVAR(1,909,"coupling_channel_element(): gain_element_scale"));

    if ((result = individual_channel_stream(hDecoder, &el_empty, ld, &ics_empty,

        0, sh_data)) > 0)

    {

        return result;

    }