2 * Copyright (c) 2007-2008 Ian Caulfield
5 * This file is part of FFmpeg.
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23 #include "libavutil/attributes.h"
27 static void mlp_filter_channel(int32_t *state, const int32_t *coeff,
28 int firorder, int iirorder,
29 unsigned int filter_shift, int32_t mask,
30 int blocksize, int32_t *sample_buffer)
32 int32_t *firbuf = state;
33 int32_t *iirbuf = state + MAX_BLOCKSIZE + MAX_FIR_ORDER;
34 const int32_t *fircoeff = coeff;
35 const int32_t *iircoeff = coeff + MAX_FIR_ORDER;
38 for (i = 0; i < blocksize; i++) {
39 int32_t residual = *sample_buffer;
44 for (order = 0; order < firorder; order++)
45 accum += (int64_t) firbuf[order] * fircoeff[order];
46 for (order = 0; order < iirorder; order++)
47 accum += (int64_t) iirbuf[order] * iircoeff[order];
49 accum = accum >> filter_shift;
50 result = (accum + residual) & mask;
53 *--iirbuf = result - accum;
55 *sample_buffer = result;
56 sample_buffer += MAX_CHANNELS;
60 av_cold void ff_mlpdsp_init(MLPDSPContext *c)
62 c->mlp_filter_channel = mlp_filter_channel;
64 ff_mlpdsp_init_x86(c);