/*

 * ALAC (Apple Lossless Audio Codec) decoder

 * Copyright (c) 2005 David Hammerton

 *

 * 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

 */

#include "libavutil/attributes.h"

#include "alacdsp.h"

#include "config.h"

static void decorrelate_stereo(int32_t *buffer[2], int nb_samples,

                               int decorr_shift, int decorr_left_weight)

{

    int i;

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

        uint32_t a, b;

        a = buffer[0][i];

        b = buffer[1][i];

        a -= (int)(b * decorr_left_weight) >> decorr_shift;

        b += a;

        buffer[0][i] = b;

        buffer[1][i] = a;

    }

}

static void append_extra_bits(int32_t *buffer[2], int32_t *extra_bits_buffer[2],

                              int extra_bits, int channels, int nb_samples)

{

    int i, ch;

    for (ch = 0; ch < channels; ch++)

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

            buffer[ch][i] = ((unsigned)buffer[ch][i] << extra_bits) | extra_bits_buffer[ch][i];

}

av_cold void ff_alacdsp_init(ALACDSPContext *c)

{

    c->decorrelate_stereo   = decorrelate_stereo;

    c->append_extra_bits[0] =

    c->append_extra_bits[1] = append_extra_bits;

#if ARCH_RISCV

    ff_alacdsp_init_riscv(c);

#elif ARCH_X86 && HAVE_X86ASM

    ff_alacdsp_init_x86(c);

#endif

}