1/*
2 * Copyright (c) 2004 Michael Niedermayer <michaelni@gmx.at>
3 *
4 * This file is part of FFmpeg.
5 *
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21#include <math.h>
22#include <stdint.h>
23
24#include "libavutil/common.h"
25#include "internal.h"
26
27#if defined(CONFIG_RESAMPLE_DBL)
28#define SET_TYPE(func)  func ## _dbl
29#define FELEM         double
30#define FELEM2        double
31#define FELEML        double
32#define OUT(d, v) d = v
33#define DBL_TO_FELEM(d, v) d = v
34#elif defined(CONFIG_RESAMPLE_FLT)
35#define SET_TYPE(func)  func ## _flt
36#define FELEM         float
37#define FELEM2        float
38#define FELEML        float
39#define OUT(d, v) d = v
40#define DBL_TO_FELEM(d, v) d = v
41#elif defined(CONFIG_RESAMPLE_S32)
42#define SET_TYPE(func)  func ## _s32
43#define FELEM         int32_t
44#define FELEM2        int64_t
45#define FELEML        int64_t
46#define OUT(d, v) d = av_clipl_int32((v + (1 << 29)) >> 30)
47#define DBL_TO_FELEM(d, v) d = av_clipl_int32(llrint(v * (1 << 30)));
48#else
49#define SET_TYPE(func)  func ## _s16
50#define FELEM         int16_t
51#define FELEM2        int32_t
52#define FELEML        int64_t
53#define OUT(d, v) d = av_clip_int16((v + (1 << 14)) >> 15)
54#define DBL_TO_FELEM(d, v) d = av_clip_int16(lrint(v * (1 << 15)))
55#endif
56
57static void SET_TYPE(resample_nearest)(void *dst0, int dst_index, const void *src0, unsigned int index)
58{
59    FELEM *dst = dst0;
60    const FELEM *src = src0;
61    dst[dst_index] = src[index];
62}
63
64static void SET_TYPE(resample_linear)(ResampleContext *c, void *dst0, int dst_index,
65                                      const void *src0, unsigned int index, int frac)
66{
67    FELEM *dst = dst0;
68    const FELEM *src = src0;
69    int i;
70    unsigned int sample_index = index >> c->phase_shift;
71    FELEM2 val = 0;
72    FELEM *filter = ((FELEM *)c->filter_bank) +
73                    c->filter_length * (index & c->phase_mask);
74    FELEM2 v2 = 0;
75
76    for (i = 0; i < c->filter_length; i++) {
77        val += src[sample_index + i] * (FELEM2)filter[i];
78        v2  += src[sample_index + i] * (FELEM2)filter[i + c->filter_length];
79    }
80    val += (v2 - val) * (FELEML)frac / c->src_incr;
81
82    OUT(dst[dst_index], val);
83}
84
85static void SET_TYPE(resample_one)(ResampleContext *c,
86                                   void *dst0, int dst_index, const void *src0,
87                                   unsigned int index, int frac)
88{
89    FELEM *dst = dst0;
90    const FELEM *src = src0;
91    int i;
92    unsigned int sample_index = index >> c->phase_shift;
93    FELEM2 val = 0;
94    FELEM *filter = ((FELEM *)c->filter_bank) +
95                    c->filter_length * (index & c->phase_mask);
96
97    for (i = 0; i < c->filter_length; i++)
98        val += src[sample_index + i] * (FELEM2)filter[i];
99
100    OUT(dst[dst_index], val);
101}
102
103static void SET_TYPE(set_filter)(void *filter0, double *tab, int phase,
104                                 int tap_count)
105{
106    int i;
107    FELEM *filter = ((FELEM *)filter0) + phase * tap_count;
108    for (i = 0; i < tap_count; i++) {
109        DBL_TO_FELEM(filter[i], tab[i]);
110    }
111}
112
113#undef SET_TYPE
114#undef FELEM
115#undef FELEM2
116#undef FELEML
117#undef OUT
118#undef DBL_TO_FELEM
119