ffmpeg/libavcodec/fmtconvert.c

/*
 * Format Conversion Utils
 * Copyright (c) 2000, 2001 Fabrice Bellard
 * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
 *
 * 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 "avcodec.h"
#include "fmtconvert.h"
#include "libavutil/common.h"

static void int32_to_float_fmul_scalar_c(float *dst, const int32_t *src,
                                         float mul, int len)
{
    int i;
    for(i=0; i<len; i++)
        dst[i] = src[i] * mul;
}

static void int32_to_float_fmul_array8_c(FmtConvertContext *c, float *dst,
                                         const int32_t *src, const float *mul,
                                         int len)
{
    int i;
    for (i = 0; i < len; i += 8)
        c->int32_to_float_fmul_scalar(&dst[i], &src[i], *mul++, 8);
}

av_cold void ff_fmt_convert_init(FmtConvertContext *c, AVCodecContext *avctx)
{
    c->int32_to_float_fmul_scalar = int32_to_float_fmul_scalar_c;
    c->int32_to_float_fmul_array8 = int32_to_float_fmul_array8_c;

    if (ARCH_ARM) ff_fmt_convert_init_arm(c, avctx);
    if (ARCH_PPC) ff_fmt_convert_init_ppc(c, avctx);
    if (ARCH_X86) ff_fmt_convert_init_x86(c, avctx);
    if (HAVE_MIPSFPU) ff_fmt_convert_init_mips(c);
}

/* ffdshow custom code */
void float_interleave(float *dst, const float **src, long len, int channels)
{
    int i,j,c;
    if(channels==2){
        for(i=0; i<len; i++){
            dst[2*i]   = src[0][i] / 32768.0f;
            dst[2*i+1] = src[1][i] / 32768.0f;
        }
    }else{
        for(c=0; c<channels; c++)
            for(i=0, j=c; i<len; i++, j+=channels)
                dst[j] = src[c][i] / 32768.0f;
    }
}

void float_interleave_noscale(float *dst, const float **src, long len, int channels)
{
    int i,j,c;
    if(channels==2){
        for(i=0; i<len; i++){
            dst[2*i]   = src[0][i];
            dst[2*i+1] = src[1][i];
        }
    }else{
        for(c=0; c<channels; c++)
            for(i=0, j=c; i<len; i++, j+=channels)
                dst[j] = src[c][i];
    }
}