Imported Debian version 2.5.2~trusty
[deb_ffmpeg.git] / ffmpeg / libswresample / resample_template.c
1 /*
2 * audio resampling
3 * Copyright (c) 2004-2012 Michael Niedermayer <michaelni@gmx.at>
4 *
5 * This file is part of FFmpeg.
6 *
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.
11 *
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.
16 *
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
20 */
21
22 /**
23 * @file
24 * audio resampling
25 * @author Michael Niedermayer <michaelni@gmx.at>
26 */
27
28 #if defined(TEMPLATE_RESAMPLE_DBL)
29
30 # define RENAME(N) N ## _double
31 # define FILTER_SHIFT 0
32 # define DELEM double
33 # define FELEM double
34 # define FELEM2 double
35 # define OUT(d, v) d = v
36
37 #elif defined(TEMPLATE_RESAMPLE_FLT)
38
39 # define RENAME(N) N ## _float
40 # define FILTER_SHIFT 0
41 # define DELEM float
42 # define FELEM float
43 # define FELEM2 float
44 # define OUT(d, v) d = v
45
46 #elif defined(TEMPLATE_RESAMPLE_S32)
47
48 # define RENAME(N) N ## _int32
49 # define FILTER_SHIFT 30
50 # define DELEM int32_t
51 # define FELEM int32_t
52 # define FELEM2 int64_t
53 # define FELEM_MAX INT32_MAX
54 # define FELEM_MIN INT32_MIN
55 # define OUT(d, v) v = (v + (1<<(FILTER_SHIFT-1)))>>FILTER_SHIFT;\
56 d = (uint64_t)(v + 0x80000000) > 0xFFFFFFFF ? (v>>63) ^ 0x7FFFFFFF : v
57
58 #elif defined(TEMPLATE_RESAMPLE_S16)
59
60 # define RENAME(N) N ## _int16
61 # define FILTER_SHIFT 15
62 # define DELEM int16_t
63 # define FELEM int16_t
64 # define FELEM2 int32_t
65 # define FELEML int64_t
66 # define FELEM_MAX INT16_MAX
67 # define FELEM_MIN INT16_MIN
68 # define OUT(d, v) v = (v + (1<<(FILTER_SHIFT-1)))>>FILTER_SHIFT;\
69 d = (unsigned)(v + 32768) > 65535 ? (v>>31) ^ 32767 : v
70
71 #endif
72
73 static void RENAME(resample_one)(void *dest, const void *source,
74 int dst_size, int64_t index2, int64_t incr)
75 {
76 DELEM *dst = dest;
77 const DELEM *src = source;
78 int dst_index;
79
80 for (dst_index = 0; dst_index < dst_size; dst_index++) {
81 dst[dst_index] = src[index2 >> 32];
82 index2 += incr;
83 }
84 }
85
86 static int RENAME(resample_common)(ResampleContext *c,
87 void *dest, const void *source,
88 int n, int update_ctx)
89 {
90 DELEM *dst = dest;
91 const DELEM *src = source;
92 int dst_index;
93 int index= c->index;
94 int frac= c->frac;
95 int sample_index = index >> c->phase_shift;
96
97 index &= c->phase_mask;
98 for (dst_index = 0; dst_index < n; dst_index++) {
99 FELEM *filter = ((FELEM *) c->filter_bank) + c->filter_alloc * index;
100
101 FELEM2 val=0;
102 int i;
103 for (i = 0; i < c->filter_length; i++) {
104 val += src[sample_index + i] * (FELEM2)filter[i];
105 }
106 OUT(dst[dst_index], val);
107
108 frac += c->dst_incr_mod;
109 index += c->dst_incr_div;
110 if (frac >= c->src_incr) {
111 frac -= c->src_incr;
112 index++;
113 }
114 sample_index += index >> c->phase_shift;
115 index &= c->phase_mask;
116 }
117
118 if(update_ctx){
119 c->frac= frac;
120 c->index= index;
121 }
122
123 return sample_index;
124 }
125
126 static int RENAME(resample_linear)(ResampleContext *c,
127 void *dest, const void *source,
128 int n, int update_ctx)
129 {
130 DELEM *dst = dest;
131 const DELEM *src = source;
132 int dst_index;
133 int index= c->index;
134 int frac= c->frac;
135 int sample_index = index >> c->phase_shift;
136 #if FILTER_SHIFT == 0
137 double inv_src_incr = 1.0 / c->src_incr;
138 #endif
139
140 index &= c->phase_mask;
141 for (dst_index = 0; dst_index < n; dst_index++) {
142 FELEM *filter = ((FELEM *) c->filter_bank) + c->filter_alloc * index;
143 FELEM2 val=0, v2 = 0;
144
145 int i;
146 for (i = 0; i < c->filter_length; i++) {
147 val += src[sample_index + i] * (FELEM2)filter[i];
148 v2 += src[sample_index + i] * (FELEM2)filter[i + c->filter_alloc];
149 }
150 #ifdef FELEML
151 val += (v2 - val) * (FELEML) frac / c->src_incr;
152 #else
153 # if FILTER_SHIFT == 0
154 val += (v2 - val) * inv_src_incr * frac;
155 # else
156 val += (v2 - val) / c->src_incr * frac;
157 # endif
158 #endif
159 OUT(dst[dst_index], val);
160
161 frac += c->dst_incr_mod;
162 index += c->dst_incr_div;
163 if (frac >= c->src_incr) {
164 frac -= c->src_incr;
165 index++;
166 }
167 sample_index += index >> c->phase_shift;
168 index &= c->phase_mask;
169 }
170
171 if(update_ctx){
172 c->frac= frac;
173 c->index= index;
174 }
175
176 return sample_index;
177 }
178
179 #undef RENAME
180 #undef FILTER_SHIFT
181 #undef DELEM
182 #undef FELEM
183 #undef FELEM2
184 #undef FELEML
185 #undef FELEM_MAX
186 #undef FELEM_MIN
187 #undef OUT