/*
** 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: ssr_fb.c,v 1.17 2007/11/01 12:33:36 menno Exp $
**/

#include "common.h"
#include "structs.h"

#ifdef SSR_DEC

#include <string.h>
#include <stdlib.h>
#include "syntax.h"
#include "filtbank.h"
#include "mdct.h"
#include "ssr_fb.h"
#include "ssr_win.h"

fb_info *ssr_filter_bank_init(uint16_t frame_len)
{
    uint16_t nshort = frame_len / 8;

    fb_info *fb = (fb_info*)faad_malloc(sizeof(fb_info));
    memset(fb, 0, sizeof(fb_info));

    /* normal */
    fb->mdct256 = faad_mdct_init(2 * nshort);
    fb->mdct2048 = faad_mdct_init(2 * frame_len);

    fb->long_window[0]  = sine_long_256;
    fb->short_window[0] = sine_short_32;
    fb->long_window[1]  = kbd_long_256;
    fb->short_window[1] = kbd_short_32;

    fb->process_buf = calloc(2 * 1024, sizeof(real_t));
    if (fb->process_buf) {
        fb->process_buf_size = 2 * 1024 * sizeof(real_t);
    } else {
        fb->process_buf_size = 0;
    }
    fb->process_buf2 = calloc(2 * 1024, sizeof(real_t));
    if (fb->process_buf2) {
        fb->process_buf_size2 = 2 * 1024 * sizeof(real_t);
    } else {
        fb->process_buf_size2 = 0;
    }

    return fb;
}

void ssr_filter_bank_end(fb_info *fb)
{
    faad_mdct_end(fb->mdct256);
    faad_mdct_end(fb->mdct2048);

    if (fb->process_buf) {
        free(fb->process_buf);
        fb->process_buf = NULL;
    }
    if (fb->process_buf2) {
        free(fb->process_buf2);
        fb->process_buf2 = NULL;
    }

    if (fb) {
        faad_free(fb);
    }
}

static INLINE void imdct_ssr(fb_info *fb, real_t *in_data,
                             real_t *out_data, uint16_t len)
{
    mdct_info *mdct;

    switch (len) {
    case 512:
        mdct = fb->mdct2048;
        break;
    case 64:
        mdct = fb->mdct256;
        break;
    }

    faad_imdct(mdct, in_data, out_data);
}

/* NON-overlapping inverse filterbank for use with SSR */
void ssr_ifilter_bank(fb_info *fb, uint8_t window_sequence, uint8_t window_shape,
                      uint8_t window_shape_prev, real_t *freq_in,
                      real_t *time_out, uint16_t frame_len)
{
    int16_t i;
    real_t *transf_buf;

    real_t *window_long;
    real_t *window_long_prev;
    real_t *window_short;
    real_t *window_short_prev;

    uint16_t nlong = frame_len;
    uint16_t nshort = frame_len / 8;
    uint16_t trans = nshort / 2;

    uint16_t nflat_ls = (nlong - nshort) / 2;

    transf_buf = (real_t*)faad_malloc(2 * nlong * sizeof(real_t));

    window_long       = fb->long_window[window_shape];
    window_long_prev  = fb->long_window[window_shape_prev];
    window_short      = fb->short_window[window_shape];
    window_short_prev = fb->short_window[window_shape_prev];

    switch (window_sequence) {
    case ONLY_LONG_SEQUENCE:
        imdct_ssr(fb, freq_in, transf_buf, 2 * nlong);
        for (i = nlong - 1; i >= 0; i--) {
            time_out[i] = MUL_R_C(transf_buf[i], window_long_prev[i]);
            time_out[nlong + i] = MUL_R_C(transf_buf[nlong + i], window_long[nlong - 1 - i]);
        }
        break;

    case LONG_START_SEQUENCE:
        imdct_ssr(fb, freq_in, transf_buf, 2 * nlong);
        for (i = 0; i < nlong; i++) {
            time_out[i] = MUL_R_C(transf_buf[i], window_long_prev[i]);
        }
        for (i = 0; i < nflat_ls; i++) {
            time_out[nlong + i] = transf_buf[nlong + i];
        }
        for (i = 0; i < nshort; i++) {
            time_out[nlong + nflat_ls + i] = MUL_R_C(transf_buf[nlong + nflat_ls + i], window_short[nshort - i - 1]);
        }
        for (i = 0; i < nflat_ls; i++) {
            time_out[nlong + nflat_ls + nshort + i] = 0;
        }
        break;

    case EIGHT_SHORT_SEQUENCE:
        imdct_ssr(fb, freq_in + 0 * nshort, transf_buf + 2 * nshort * 0, 2 * nshort);
        imdct_ssr(fb, freq_in + 1 * nshort, transf_buf + 2 * nshort * 1, 2 * nshort);
        imdct_ssr(fb, freq_in + 2 * nshort, transf_buf + 2 * nshort * 2, 2 * nshort);
        imdct_ssr(fb, freq_in + 3 * nshort, transf_buf + 2 * nshort * 3, 2 * nshort);
        imdct_ssr(fb, freq_in + 4 * nshort, transf_buf + 2 * nshort * 4, 2 * nshort);
        imdct_ssr(fb, freq_in + 5 * nshort, transf_buf + 2 * nshort * 5, 2 * nshort);
        imdct_ssr(fb, freq_in + 6 * nshort, transf_buf + 2 * nshort * 6, 2 * nshort);
        imdct_ssr(fb, freq_in + 7 * nshort, transf_buf + 2 * nshort * 7, 2 * nshort);
        for (i = nshort - 1; i >= 0; i--) {
            time_out[i + 0 * nshort] = MUL_R_C(transf_buf[nshort * 0 + i], window_short_prev[i]);
            time_out[i + 1 * nshort] = MUL_R_C(transf_buf[nshort * 1 + i], window_short[i]);
            time_out[i + 2 * nshort] = MUL_R_C(transf_buf[nshort * 2 + i], window_short_prev[i]);
            time_out[i + 3 * nshort] = MUL_R_C(transf_buf[nshort * 3 + i], window_short[i]);
            time_out[i + 4 * nshort] = MUL_R_C(transf_buf[nshort * 4 + i], window_short_prev[i]);
            time_out[i + 5 * nshort] = MUL_R_C(transf_buf[nshort * 5 + i], window_short[i]);
            time_out[i + 6 * nshort] = MUL_R_C(transf_buf[nshort * 6 + i], window_short_prev[i]);
            time_out[i + 7 * nshort] = MUL_R_C(transf_buf[nshort * 7 + i], window_short[i]);
            time_out[i + 8 * nshort] = MUL_R_C(transf_buf[nshort * 8 + i], window_short_prev[i]);
            time_out[i + 9 * nshort] = MUL_R_C(transf_buf[nshort * 9 + i], window_short[i]);
            time_out[i + 10 * nshort] = MUL_R_C(transf_buf[nshort * 10 + i], window_short_prev[i]);
            time_out[i + 11 * nshort] = MUL_R_C(transf_buf[nshort * 11 + i], window_short[i]);
            time_out[i + 12 * nshort] = MUL_R_C(transf_buf[nshort * 12 + i], window_short_prev[i]);
            time_out[i + 13 * nshort] = MUL_R_C(transf_buf[nshort * 13 + i], window_short[i]);
            time_out[i + 14 * nshort] = MUL_R_C(transf_buf[nshort * 14 + i], window_short_prev[i]);
            time_out[i + 15 * nshort] = MUL_R_C(transf_buf[nshort * 15 + i], window_short[i]);
        }
        break;

    case LONG_STOP_SEQUENCE:
        imdct_ssr(fb, freq_in, transf_buf, 2 * nlong);
        for (i = 0; i < nflat_ls; i++) {
            time_out[i] = 0;
        }
        for (i = 0; i < nshort; i++) {
            time_out[nflat_ls + i] = MUL_R_C(transf_buf[nflat_ls + i], window_short_prev[i]);
        }
        for (i = 0; i < nflat_ls; i++) {
            time_out[nflat_ls + nshort + i] = transf_buf[nflat_ls + nshort + i];
        }
        for (i = 0; i < nlong; i++) {
            time_out[nlong + i] = MUL_R_C(transf_buf[nlong + i], window_long[nlong - 1 - i]);
        }
        break;
    }

    faad_free(transf_buf);
}


#endif