ffmpeg/libavcodec/g722dsp.c
Peter Meerwald 6769068313 g722: Split out g722_qmf_apply() function into g722dsp.c
Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: Martin Storsjö <martin@martin.st>
2015-02-15 22:47:10 +02:00

48 lines
1.5 KiB
C

/*
* Copyright (c) 2015 Peter Meerwald <pmeerw@pmeerw.net>
*
* 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 "g722dsp.h"
#include "mathops.h"
/*
* quadrature mirror filter (QMF) coefficients (ITU-T G.722 Table 11) inlined
* in code below: 3, -11, 12, 32, -210, 951, 3876, -805, 362, -156, 53, -11
*/
static const int16_t qmf_coeffs[12] = {
3, -11, 12, 32, -210, 951, 3876, -805, 362, -156, 53, -11,
};
static void g722_apply_qmf(const int16_t *prev_samples, int *xout1, int *xout2)
{
int i;
*xout1 = 0;
*xout2 = 0;
for (i = 0; i < 12; i++) {
MAC16(*xout2, prev_samples[2*i ], qmf_coeffs[i ]);
MAC16(*xout1, prev_samples[2*i+1], qmf_coeffs[11-i]);
}
}
av_cold void ff_g722dsp_init(G722DSPContext *c)
{
c->apply_qmf = g722_apply_qmf;
}