ffmpeg/libavcodec/dcadsp.c

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/*
* Copyright (c) 2004 Gildas Bazin
* Copyright (c) 2010 Mans Rullgard <mans@mansr.com>
*
* This file is part of Libav.
*
* Libav 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.
*
* Libav 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 Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "config.h"
#include "dcadsp.h"
static void dca_lfe_fir_c(float *out, const float *in, const float *coefs,
int decifactor, float scale)
{
float *out2 = out + decifactor;
const float *cf0 = coefs;
const float *cf1 = coefs + 256;
int j, k;
/* One decimated sample generates 2*decifactor interpolated ones */
for (k = 0; k < decifactor; k++) {
float v0 = 0.0;
float v1 = 0.0;
for (j = 0; j < 256 / decifactor; j++) {
float s = in[-j];
v0 += s * *cf0++;
v1 += s * *--cf1;
}
*out++ = v0 * scale;
*out2++ = v1 * scale;
}
}
void ff_dcadsp_init(DCADSPContext *s)
{
s->lfe_fir = dca_lfe_fir_c;
if (ARCH_ARM) ff_dcadsp_init_arm(s);
}