mirror of https://git.ffmpeg.org/ffmpeg.git
48 lines
1.5 KiB
C
48 lines
1.5 KiB
C
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/*
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* Copyright (c) 2015 Peter Meerwald <pmeerw@pmeerw.net>
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*
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* This file is part of Libav.
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*
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* Libav is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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*
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* Libav is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with Libav; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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#include "g722dsp.h"
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#include "mathops.h"
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/*
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* quadrature mirror filter (QMF) coefficients (ITU-T G.722 Table 11) inlined
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* in code below: 3, -11, 12, 32, -210, 951, 3876, -805, 362, -156, 53, -11
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*/
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static const int16_t qmf_coeffs[12] = {
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3, -11, 12, 32, -210, 951, 3876, -805, 362, -156, 53, -11,
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};
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static void g722_apply_qmf(const int16_t *prev_samples, int *xout1, int *xout2)
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{
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int i;
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*xout1 = 0;
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*xout2 = 0;
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for (i = 0; i < 12; i++) {
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MAC16(*xout2, prev_samples[2*i ], qmf_coeffs[i ]);
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MAC16(*xout1, prev_samples[2*i+1], qmf_coeffs[11-i]);
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}
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}
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av_cold void ff_g722dsp_init(G722DSPContext *c)
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{
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c->apply_qmf = g722_apply_qmf;
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}
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