/*

 * AAC decoder

 * Copyright (c) 2005-2006 Oded Shimon ( ods15 ods15 dyndns org )

 * Copyright (c) 2006-2007 Maxim Gavrilov ( maxim.gavrilov gmail com )

 * Copyright (c) 2008-2013 Alex Converse <alex.converse@gmail.com>

 *

 * AAC LATM decoder

 * Copyright (c) 2008-2010 Paul Kendall <paul@kcbbs.gen.nz>

 * Copyright (c) 2010      Janne Grunau <janne-libav@jannau.net>

 *

 * AAC decoder fixed-point implementation

 * Copyright (c) 2013

 *      MIPS Technologies, Inc., California.

 *

 * This file is part of FFmpeg.

 *

 * FFmpeg is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 of the License, or (at your option) any later version.

 *

 * FFmpeg 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

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with FFmpeg; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

 */

#ifndef AVCODEC_AAC_AACDEC_FIXED_DEQUANT_H

#define AVCODEC_AAC_AACDEC_FIXED_DEQUANT_H

#include "aacdec_tab.h"

static void inline vector_pow43(int *coefs, int len)

{

    int i, coef;

    for (i=0; i<len; i++) {

        coef = coefs[i];

        if (coef < 0)

            coef = -(int)ff_cbrt_tab_fixed[(-coef) & 8191];

        else

            coef =  (int)ff_cbrt_tab_fixed[  coef  & 8191];

        coefs[i] = coef;

    }

}

/* 2^0, 2^0.25, 2^0.5, 2^0.75 */

static const int exp2tab[4] = {

    Q31(1.0000000000/2), Q31(1.1892071150/2),

    Q31(1.4142135624/2), Q31(1.6817928305/2)

};

static void inline subband_scale(int *dst, int *src, int scale,

                                 int offset, int len, void *log_context)

{

    int ssign = scale < 0 ? -1 : 1;

    int s = FFABS(scale);

    unsigned int round;

    int i, out, c = exp2tab[s & 3];

    s = offset - (s >> 2);

    if (s > 31) {

        for (i=0; i<len; i++) {

            dst[i] = 0;

        }

    } else if (s > 0) {

        round = 1 << (s-1);

        for (i=0; i<len; i++) {

            out = (int)(((int64_t)src[i] * c) >> 32);

            dst[i] = ((int)(out+round) >> s) * ssign;

        }

    } else if (s > -32) {

        s = s + 32;

        round = 1U << (s-1);

        for (i=0; i<len; i++) {

            out = (int)((int64_t)((int64_t)src[i] * c + round) >> s);

            dst[i] = out * (unsigned)ssign;

        }

    } else {

        av_log(log_context, AV_LOG_ERROR, "Overflow in subband_scale()\n");

    }

}

static void noise_scale(int *coefs, int scale, int band_energy, int len)

{

    int s = -scale;

    unsigned int round;

    int i, out, c = exp2tab[s & 3];

    int nlz = 0;

    av_assert0(s >= 0);

    while (band_energy > 0x7fff) {

        band_energy >>= 1;

        nlz++;

    }

    c /= band_energy;

    s = 21 + nlz - (s >> 2);

    if (s > 31) {

        for (i=0; i<len; i++) {

            coefs[i] = 0;

        }

    } else if (s >= 0) {

        round = s ? 1 << (s-1) : 0;

        for (i=0; i<len; i++) {

            out = (int)(((int64_t)coefs[i] * c) >> 32);

            coefs[i] = -((int)(out+round) >> s);

        }

    }

    else {

        s = s + 32;

        if (s > 0) {

            round = 1 << (s-1);

            for (i=0; i<len; i++) {

                out = (int)((int64_t)((int64_t)coefs[i] * c + round) >> s);

                coefs[i] = -out;

            }

        } else {

            for (i=0; i<len; i++)

                coefs[i] = -(int64_t)coefs[i] * c * (1 << -s);

        }

    }

}

static inline int *DEC_SPAIR(int *dst, unsigned idx)

{

    dst[0] = (idx & 15) - 4;

    dst[1] = (idx >> 4 & 15) - 4;

    return dst + 2;

}

static inline int *DEC_SQUAD(int *dst, unsigned idx)

{

    dst[0] = (idx & 3) - 1;

    dst[1] = (idx >> 2 & 3) - 1;

    dst[2] = (idx >> 4 & 3) - 1;

    dst[3] = (idx >> 6 & 3) - 1;

    return dst + 4;

}

static inline int *DEC_UPAIR(int *dst, unsigned idx, unsigned sign)

{

    dst[0] = (idx & 15) * (1 - (sign & 0xFFFFFFFE));

    dst[1] = (idx >> 4 & 15) * (1 - ((sign & 1) * 2));

    return dst + 2;

}

static inline int *DEC_UQUAD(int *dst, unsigned idx, unsigned sign)

{

    unsigned nz = idx >> 12;

    dst[0] = (idx & 3) * (1 + (((int)sign >> 31) * 2));

    sign <<= nz & 1;

    nz >>= 1;

    dst[1] = (idx >> 2 & 3) * (1 + (((int)sign >> 31) * 2));

    sign <<= nz & 1;

    nz >>= 1;

    dst[2] = (idx >> 4 & 3) * (1 + (((int)sign >> 31) * 2));

    sign <<= nz & 1;

    nz >>= 1;

    dst[3] = (idx >> 6 & 3) * (1 + (((int)sign >> 31) * 2));

    return dst + 4;

}

#endif /* AVCODEC_AAC_AACDEC_FIXED_DEQUANT_H */