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resample_template.c
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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 FOFFSET 0
36 # define OUT(d, v) d = v
37 
38 #elif defined(TEMPLATE_RESAMPLE_FLT)
39 
40 # define RENAME(N) N ## _float
41 # define FILTER_SHIFT 0
42 # define DELEM float
43 # define FELEM float
44 # define FELEM2 float
45 # define FOFFSET 0
46 # define OUT(d, v) d = v
47 
48 #elif defined(TEMPLATE_RESAMPLE_S32)
49 
50 # define RENAME(N) N ## _int32
51 # define FILTER_SHIFT 30
52 # define DELEM int32_t
53 # define FELEM int32_t
54 # define FELEM2 int64_t
55 # define FELEM_MAX INT32_MAX
56 # define FELEM_MIN INT32_MIN
57 # define FOFFSET (1<<(FILTER_SHIFT-1))
58 # define OUT(d, v) (d) = av_clipl_int32((v)>>FILTER_SHIFT)
59 
60 #elif defined(TEMPLATE_RESAMPLE_S16)
61 
62 # define RENAME(N) N ## _int16
63 # define FILTER_SHIFT 15
64 # define DELEM int16_t
65 # define FELEM int16_t
66 # define FELEM2 int32_t
67 # define FELEML int64_t
68 # define FELEM_MAX INT16_MAX
69 # define FELEM_MIN INT16_MIN
70 # define FOFFSET (1<<(FILTER_SHIFT-1))
71 # define OUT(d, v) (d) = av_clip_int16((v)>>FILTER_SHIFT)
72 
73 #endif
74 
75 static void RENAME(resample_one)(void *dest, const void *source,
76  int dst_size, int64_t index2, int64_t incr)
77 {
78  DELEM *dst = dest;
79  const DELEM *src = source;
80  int dst_index;
81 
82  for (dst_index = 0; dst_index < dst_size; dst_index++) {
83  dst[dst_index] = src[index2 >> 32];
84  index2 += incr;
85  }
86 }
87 
89  void *dest, const void *source,
90  int n, int update_ctx)
91 {
92  DELEM *dst = dest;
93  const DELEM *src = source;
94  int dst_index;
95  int index= c->index;
96  int frac= c->frac;
97  int sample_index = 0;
98 
99  while (index >= c->phase_count) {
100  sample_index++;
101  index -= c->phase_count;
102  }
103 
104  for (dst_index = 0; dst_index < n; dst_index++) {
105  FELEM *filter = ((FELEM *) c->filter_bank) + c->filter_alloc * index;
106 
107  FELEM2 val = FOFFSET;
108  FELEM2 val2= 0;
109  int i;
110  for (i = 0; i + 1 < c->filter_length; i+=2) {
111  val += src[sample_index + i ] * (FELEM2)filter[i ];
112  val2 += src[sample_index + i + 1] * (FELEM2)filter[i + 1];
113  }
114  if (i < c->filter_length)
115  val += src[sample_index + i ] * (FELEM2)filter[i ];
116 #ifdef FELEML
117  OUT(dst[dst_index], val + (FELEML)val2);
118 #else
119  OUT(dst[dst_index], val + val2);
120 #endif
121 
122  frac += c->dst_incr_mod;
123  index += c->dst_incr_div;
124  if (frac >= c->src_incr) {
125  frac -= c->src_incr;
126  index++;
127  }
128 
129  while (index >= c->phase_count) {
130  sample_index++;
131  index -= c->phase_count;
132  }
133  }
134 
135  if(update_ctx){
136  c->frac= frac;
137  c->index= index;
138  }
139 
140  return sample_index;
141 }
142 
144  void *dest, const void *source,
145  int n, int update_ctx)
146 {
147  DELEM *dst = dest;
148  const DELEM *src = source;
149  int dst_index;
150  int index= c->index;
151  int frac= c->frac;
152  int sample_index = 0;
153 #if FILTER_SHIFT == 0
154  double inv_src_incr = 1.0 / c->src_incr;
155 #endif
156 
157  while (index >= c->phase_count) {
158  sample_index++;
159  index -= c->phase_count;
160  }
161 
162  for (dst_index = 0; dst_index < n; dst_index++) {
163  FELEM *filter = ((FELEM *) c->filter_bank) + c->filter_alloc * index;
164  FELEM2 val = FOFFSET, v2 = FOFFSET;
165 
166  int i;
167  for (i = 0; i < c->filter_length; i++) {
168  val += src[sample_index + i] * (FELEM2)filter[i];
169  v2 += src[sample_index + i] * (FELEM2)filter[i + c->filter_alloc];
170  }
171 #ifdef FELEML
172  val += (v2 - val) * (FELEML) frac / c->src_incr;
173 #else
174 # if FILTER_SHIFT == 0
175  val += (v2 - val) * inv_src_incr * frac;
176 # else
177  val += (v2 - val) / c->src_incr * frac;
178 # endif
179 #endif
180  OUT(dst[dst_index], val);
181 
182  frac += c->dst_incr_mod;
183  index += c->dst_incr_div;
184  if (frac >= c->src_incr) {
185  frac -= c->src_incr;
186  index++;
187  }
188 
189  while (index >= c->phase_count) {
190  sample_index++;
191  index -= c->phase_count;
192  }
193  }
194 
195  if(update_ctx){
196  c->frac= frac;
197  c->index= index;
198  }
199 
200  return sample_index;
201 }
202 
203 #undef RENAME
204 #undef FILTER_SHIFT
205 #undef DELEM
206 #undef FELEM
207 #undef FELEM2
208 #undef FELEML
209 #undef FELEM_MAX
210 #undef FELEM_MIN
211 #undef OUT
212 #undef FOFFSET
const char const char void * val
Definition: avisynth_c.h:771
#define RENAME(name)
Definition: ffv1.h:205
#define src
Definition: vp8dsp.c:254
static void filter(int16_t *output, ptrdiff_t out_stride, int16_t *low, ptrdiff_t low_stride, int16_t *high, ptrdiff_t high_stride, int len, int clip)
Definition: cfhd.c:97
int16_t FELEM
Definition: resample2.c:37
int64_t FELEML
Definition: resample2.c:39
static void SET_TYPE() resample_linear(ResampleContext *c, void *dst0, int dst_index, const void *src0, unsigned int index, int frac)
static void SET_TYPE() resample_one(ResampleContext *c, void *dst0, int dst_index, const void *src0, unsigned int index, int frac)
int n
Definition: avisynth_c.h:684
int(* resample_common)(struct ResampleContext *c, void *dst, const void *src, int n, int update_ctx)
Definition: resample.h:56
int filter_length
Definition: resample.h:32
int index
Definition: gxfenc.c:89
static double c[64]
int32_t FELEM2
Definition: resample2.c:38
#define FOFFSET(x)
Definition: options.c:300