libswresample/resample_template.c
Go to the documentation of this file.
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 # define RENAME(N) N ## _double
30 # define FILTER_SHIFT 0
31 # define DELEM double
32 # define FELEM double
33 # define FELEM2 double
34 # define FELEML double
35 # define OUT(d, v) d = v
36 
37 #elif defined(TEMPLATE_RESAMPLE_FLT)
38 # define RENAME(N) N ## _float
39 # define FILTER_SHIFT 0
40 # define DELEM float
41 # define FELEM float
42 # define FELEM2 float
43 # define FELEML float
44 # define OUT(d, v) d = v
45 
46 #elif defined(TEMPLATE_RESAMPLE_S32)
47 # define RENAME(N) N ## _int32
48 # define FILTER_SHIFT 30
49 # define DELEM int32_t
50 # define FELEM int32_t
51 # define FELEM2 int64_t
52 # define FELEML 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  || defined(TEMPLATE_RESAMPLE_S16_MMX2) \
60  || defined(TEMPLATE_RESAMPLE_S16_SSSE3)
61 
62 # define FILTER_SHIFT 15
63 # define DELEM int16_t
64 # define FELEM int16_t
65 # define FELEM2 int32_t
66 # define FELEML int64_t
67 # define FELEM_MAX INT16_MAX
68 # define FELEM_MIN INT16_MIN
69 # define OUT(d, v) v = (v + (1<<(FILTER_SHIFT-1)))>>FILTER_SHIFT;\
70  d = (unsigned)(v + 32768) > 65535 ? (v>>31) ^ 32767 : v
71 
72 # if defined(TEMPLATE_RESAMPLE_S16)
73 # define RENAME(N) N ## _int16
74 # elif defined(TEMPLATE_RESAMPLE_S16_MMX2)
75 # define COMMON_CORE COMMON_CORE_INT16_MMX2
76 # define RENAME(N) N ## _int16_mmx2
77 # elif defined(TEMPLATE_RESAMPLE_S16_SSSE3)
78 # define COMMON_CORE COMMON_CORE_INT16_SSSE3
79 # define RENAME(N) N ## _int16_ssse3
80 # endif
81 
82 #endif
83 
84 int RENAME(swri_resample)(ResampleContext *c, DELEM *dst, const DELEM *src, int *consumed, int src_size, int dst_size, int update_ctx){
85  int dst_index, i;
86  int index= c->index;
87  int frac= c->frac;
88  int dst_incr_frac= c->dst_incr % c->src_incr;
89  int dst_incr= c->dst_incr / c->src_incr;
90  int compensation_distance= c->compensation_distance;
91 
92  av_assert1(c->filter_shift == FILTER_SHIFT);
93  av_assert1(c->felem_size == sizeof(FELEM));
94 
95  if(compensation_distance == 0 && c->filter_length == 1 && c->phase_shift==0){
96  int64_t index2= ((int64_t)index)<<32;
97  int64_t incr= (1LL<<32) * c->dst_incr / c->src_incr;
98  dst_size= FFMIN(dst_size, (src_size-1-index) * (int64_t)c->src_incr / c->dst_incr);
99 
100  for(dst_index=0; dst_index < dst_size; dst_index++){
101  dst[dst_index] = src[index2>>32];
102  index2 += incr;
103  }
104  index += dst_index * dst_incr;
105  index += (frac + dst_index * (int64_t)dst_incr_frac) / c->src_incr;
106  frac = (frac + dst_index * (int64_t)dst_incr_frac) % c->src_incr;
107  av_assert2(index >= 0);
108  *consumed= index >> c->phase_shift;
109  index &= c->phase_mask;
110  }else if(compensation_distance == 0 && !c->linear && index >= 0){
111  int sample_index = 0;
112  for(dst_index=0; dst_index < dst_size; dst_index++){
113  FELEM *filter;
114  sample_index += index >> c->phase_shift;
115  index &= c->phase_mask;
116  filter= ((FELEM*)c->filter_bank) + c->filter_alloc*index;
117 
118  if(sample_index + c->filter_length > src_size){
119  break;
120  }else{
121 #ifdef COMMON_CORE
122  COMMON_CORE
123 #else
124  FELEM2 val=0;
125  for(i=0; i<c->filter_length; i++){
126  val += src[sample_index + i] * (FELEM2)filter[i];
127  }
128  OUT(dst[dst_index], val);
129 #endif
130  }
131 
132  frac += dst_incr_frac;
133  index += dst_incr;
134  if(frac >= c->src_incr){
135  frac -= c->src_incr;
136  index++;
137  }
138  }
139  *consumed = sample_index;
140  }else{
141  int sample_index = 0;
142  for(dst_index=0; dst_index < dst_size; dst_index++){
143  FELEM *filter;
144  FELEM2 val=0;
145 
146  sample_index += index >> c->phase_shift;
147  index &= c->phase_mask;
148  filter = ((FELEM*)c->filter_bank) + c->filter_alloc*index;
149 
150  if(sample_index + c->filter_length > src_size || -sample_index >= src_size){
151  break;
152  }else if(sample_index < 0){
153  for(i=0; i<c->filter_length; i++)
154  val += src[FFABS(sample_index + i)] * (FELEM2)filter[i];
155  }else if(c->linear){
156  FELEM2 v2=0;
157  for(i=0; i<c->filter_length; i++){
158  val += src[sample_index + i] * (FELEM2)filter[i];
159  v2 += src[sample_index + i] * (FELEM2)filter[i + c->filter_alloc];
160  }
161  val+=(v2-val)*(FELEML)frac / c->src_incr;
162  }else{
163  for(i=0; i<c->filter_length; i++){
164  val += src[sample_index + i] * (FELEM2)filter[i];
165  }
166  }
167 
168  OUT(dst[dst_index], val);
169 
170  frac += dst_incr_frac;
171  index += dst_incr;
172  if(frac >= c->src_incr){
173  frac -= c->src_incr;
174  index++;
175  }
176 
177  if(dst_index + 1 == compensation_distance){
178  compensation_distance= 0;
179  dst_incr_frac= c->ideal_dst_incr % c->src_incr;
180  dst_incr= c->ideal_dst_incr / c->src_incr;
181  }
182  }
183  *consumed= FFMAX(sample_index, 0);
184  index += FFMIN(sample_index, 0) << c->phase_shift;
185 
186  if(compensation_distance){
187  compensation_distance -= dst_index;
188  av_assert1(compensation_distance > 0);
189  }
190  }
191 
192  if(update_ctx){
193  c->frac= frac;
194  c->index= index;
195  c->dst_incr= dst_incr_frac + c->src_incr*dst_incr;
196  c->compensation_distance= compensation_distance;
197  }
198 
199  return dst_index;
200 }
201 
202 #undef COMMON_CORE
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
swri_resample
int RENAME() swri_resample(ResampleContext *c, DELEM *dst, const DELEM *src, int *consumed, int src_size, int dst_size, int update_ctx)
Definition: libswresample/resample_template.c:84
FELEML
#define FELEML
Definition: libavresample/resample_template.c:46
av_assert2
#define av_assert2(cond)
assert() equivalent, that does lie in speed critical code.
Definition: avassert.h:63
filter
the mask is usually to keep the same permissions Filters should remove permissions on reference they give to output whenever necessary It can be automatically done by setting the rej_perms field on the output pad Here are a few guidelines corresponding to common then the filter should push the output frames on the output link immediately As an exception to the previous rule if the input frame is enough to produce several output frames then the filter needs output only at least one per link The additional frames can be left buffered in the filter
Definition: filter_design.txt:201
FELEM2
#define FELEM2
Definition: libavresample/resample_template.c:45
FELEM
#define FELEM
Definition: libavresample/resample_template.c:44
FFMAX
#define FFMAX(a, b)
Definition: common.h:56
av_assert1
#define av_assert1(cond)
assert() equivalent, that does not lie in speed critical code.
Definition: avassert.h:53
FFMIN
#define FFMIN(a, b)
Definition: common.h:58
FFABS
#define FFABS(a)
Definition: common.h:53
src
AVS_Value src
Definition: avisynth_c.h:523
OUT
#define OUT(n)
Definition: flacdsp_template.c:45
RENAME
#define RENAME(a)
Definition: mpegaudiodec.c:109
index
int index
Definition: gxfenc.c:89
i
synthesis window for stochastic i
Definition: code Kat/hpsmodel.m:34
c
static double c[64]
Definition: vsrc_mptestsrc.c:88
dst
else dst[i][x+y *dst_stride[i]]
Definition: vf_mcdeint.c:160
Generated on Wed May 8 2024 06:52:10 for FFmpeg by   doxygen 1.8.11