resample: check memory allocations in av_resample_init()
[libav.git] / libavcodec / resample2.c
1 /*
2 * audio resampling
3 * Copyright (c) 2004 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 #include "avcodec.h"
29 #include "dsputil.h"
30
31 #ifndef CONFIG_RESAMPLE_HP
32 #define FILTER_SHIFT 15
33
34 #define FELEM int16_t
35 #define FELEM2 int32_t
36 #define FELEML int64_t
37 #define FELEM_MAX INT16_MAX
38 #define FELEM_MIN INT16_MIN
39 #define WINDOW_TYPE 9
40 #elif !defined(CONFIG_RESAMPLE_AUDIOPHILE_KIDDY_MODE)
41 #define FILTER_SHIFT 30
42
43 #define FELEM int32_t
44 #define FELEM2 int64_t
45 #define FELEML int64_t
46 #define FELEM_MAX INT32_MAX
47 #define FELEM_MIN INT32_MIN
48 #define WINDOW_TYPE 12
49 #else
50 #define FILTER_SHIFT 0
51
52 #define FELEM double
53 #define FELEM2 double
54 #define FELEML double
55 #define WINDOW_TYPE 24
56 #endif
57
58
59 typedef struct AVResampleContext{
60 const AVClass *av_class;
61 FELEM *filter_bank;
62 int filter_length;
63 int ideal_dst_incr;
64 int dst_incr;
65 int index;
66 int frac;
67 int src_incr;
68 int compensation_distance;
69 int phase_shift;
70 int phase_mask;
71 int linear;
72 }AVResampleContext;
73
74 /**
75 * 0th order modified bessel function of the first kind.
76 */
77 static double bessel(double x){
78 double v=1;
79 double lastv=0;
80 double t=1;
81 int i;
82
83 x= x*x/4;
84 for(i=1; v != lastv; i++){
85 lastv=v;
86 t *= x/(i*i);
87 v += t;
88 }
89 return v;
90 }
91
92 /**
93 * builds a polyphase filterbank.
94 * @param factor resampling factor
95 * @param scale wanted sum of coefficients for each filter
96 * @param type 0->cubic, 1->blackman nuttall windowed sinc, 2..16->kaiser windowed sinc beta=2..16
97 */
98 static void build_filter(FELEM *filter, double factor, int tap_count, int phase_count, int scale, int type){
99 int ph, i;
100 double x, y, w, tab[tap_count];
101 const int center= (tap_count-1)/2;
102
103 /* if upsampling, only need to interpolate, no filter */
104 if (factor > 1.0)
105 factor = 1.0;
106
107 for(ph=0;ph<phase_count;ph++) {
108 double norm = 0;
109 for(i=0;i<tap_count;i++) {
110 x = M_PI * ((double)(i - center) - (double)ph / phase_count) * factor;
111 if (x == 0) y = 1.0;
112 else y = sin(x) / x;
113 switch(type){
114 case 0:{
115 const float d= -0.5; //first order derivative = -0.5
116 x = fabs(((double)(i - center) - (double)ph / phase_count) * factor);
117 if(x<1.0) y= 1 - 3*x*x + 2*x*x*x + d*( -x*x + x*x*x);
118 else y= d*(-4 + 8*x - 5*x*x + x*x*x);
119 break;}
120 case 1:
121 w = 2.0*x / (factor*tap_count) + M_PI;
122 y *= 0.3635819 - 0.4891775 * cos(w) + 0.1365995 * cos(2*w) - 0.0106411 * cos(3*w);
123 break;
124 default:
125 w = 2.0*x / (factor*tap_count*M_PI);
126 y *= bessel(type*sqrt(FFMAX(1-w*w, 0)));
127 break;
128 }
129
130 tab[i] = y;
131 norm += y;
132 }
133
134 /* normalize so that an uniform color remains the same */
135 for(i=0;i<tap_count;i++) {
136 #ifdef CONFIG_RESAMPLE_AUDIOPHILE_KIDDY_MODE
137 filter[ph * tap_count + i] = tab[i] / norm;
138 #else
139 filter[ph * tap_count + i] = av_clip(lrintf(tab[i] * scale / norm), FELEM_MIN, FELEM_MAX);
140 #endif
141 }
142 }
143 #if 0
144 {
145 #define LEN 1024
146 int j,k;
147 double sine[LEN + tap_count];
148 double filtered[LEN];
149 double maxff=-2, minff=2, maxsf=-2, minsf=2;
150 for(i=0; i<LEN; i++){
151 double ss=0, sf=0, ff=0;
152 for(j=0; j<LEN+tap_count; j++)
153 sine[j]= cos(i*j*M_PI/LEN);
154 for(j=0; j<LEN; j++){
155 double sum=0;
156 ph=0;
157 for(k=0; k<tap_count; k++)
158 sum += filter[ph * tap_count + k] * sine[k+j];
159 filtered[j]= sum / (1<<FILTER_SHIFT);
160 ss+= sine[j + center] * sine[j + center];
161 ff+= filtered[j] * filtered[j];
162 sf+= sine[j + center] * filtered[j];
163 }
164 ss= sqrt(2*ss/LEN);
165 ff= sqrt(2*ff/LEN);
166 sf= 2*sf/LEN;
167 maxff= FFMAX(maxff, ff);
168 minff= FFMIN(minff, ff);
169 maxsf= FFMAX(maxsf, sf);
170 minsf= FFMIN(minsf, sf);
171 if(i%11==0){
172 av_log(NULL, AV_LOG_ERROR, "i:%4d ss:%f ff:%13.6e-%13.6e sf:%13.6e-%13.6e\n", i, ss, maxff, minff, maxsf, minsf);
173 minff=minsf= 2;
174 maxff=maxsf= -2;
175 }
176 }
177 }
178 #endif
179 }
180
181 AVResampleContext *av_resample_init(int out_rate, int in_rate, int filter_size, int phase_shift, int linear, double cutoff){
182 AVResampleContext *c= av_mallocz(sizeof(AVResampleContext));
183 double factor= FFMIN(out_rate * cutoff / in_rate, 1.0);
184 int phase_count= 1<<phase_shift;
185
186 if (!c)
187 return NULL;
188
189 c->phase_shift= phase_shift;
190 c->phase_mask= phase_count-1;
191 c->linear= linear;
192
193 c->filter_length= FFMAX((int)ceil(filter_size/factor), 1);
194 c->filter_bank= av_mallocz(c->filter_length*(phase_count+1)*sizeof(FELEM));
195 if (!c->filter_bank)
196 goto error;
197 build_filter(c->filter_bank, factor, c->filter_length, phase_count, 1<<FILTER_SHIFT, WINDOW_TYPE);
198 memcpy(&c->filter_bank[c->filter_length*phase_count+1], c->filter_bank, (c->filter_length-1)*sizeof(FELEM));
199 c->filter_bank[c->filter_length*phase_count]= c->filter_bank[c->filter_length - 1];
200
201 c->src_incr= out_rate;
202 c->ideal_dst_incr= c->dst_incr= in_rate * phase_count;
203 c->index= -phase_count*((c->filter_length-1)/2);
204
205 return c;
206 error:
207 av_free(c);
208 return NULL;
209 }
210
211 void av_resample_close(AVResampleContext *c){
212 av_freep(&c->filter_bank);
213 av_freep(&c);
214 }
215
216 void av_resample_compensate(AVResampleContext *c, int sample_delta, int compensation_distance){
217 // sample_delta += (c->ideal_dst_incr - c->dst_incr)*(int64_t)c->compensation_distance / c->ideal_dst_incr;
218 c->compensation_distance= compensation_distance;
219 c->dst_incr = c->ideal_dst_incr - c->ideal_dst_incr * (int64_t)sample_delta / compensation_distance;
220 }
221
222 int av_resample(AVResampleContext *c, short *dst, short *src, int *consumed, int src_size, int dst_size, int update_ctx){
223 int dst_index, i;
224 int index= c->index;
225 int frac= c->frac;
226 int dst_incr_frac= c->dst_incr % c->src_incr;
227 int dst_incr= c->dst_incr / c->src_incr;
228 int compensation_distance= c->compensation_distance;
229
230 if(compensation_distance == 0 && c->filter_length == 1 && c->phase_shift==0){
231 int64_t index2= ((int64_t)index)<<32;
232 int64_t incr= (1LL<<32) * c->dst_incr / c->src_incr;
233 dst_size= FFMIN(dst_size, (src_size-1-index) * (int64_t)c->src_incr / c->dst_incr);
234
235 for(dst_index=0; dst_index < dst_size; dst_index++){
236 dst[dst_index] = src[index2>>32];
237 index2 += incr;
238 }
239 frac += dst_index * dst_incr_frac;
240 index += dst_index * dst_incr;
241 index += frac / c->src_incr;
242 frac %= c->src_incr;
243 }else{
244 for(dst_index=0; dst_index < dst_size; dst_index++){
245 FELEM *filter= c->filter_bank + c->filter_length*(index & c->phase_mask);
246 int sample_index= index >> c->phase_shift;
247 FELEM2 val=0;
248
249 if(sample_index < 0){
250 for(i=0; i<c->filter_length; i++)
251 val += src[FFABS(sample_index + i) % src_size] * filter[i];
252 }else if(sample_index + c->filter_length > src_size){
253 break;
254 }else if(c->linear){
255 FELEM2 v2=0;
256 for(i=0; i<c->filter_length; i++){
257 val += src[sample_index + i] * (FELEM2)filter[i];
258 v2 += src[sample_index + i] * (FELEM2)filter[i + c->filter_length];
259 }
260 val+=(v2-val)*(FELEML)frac / c->src_incr;
261 }else{
262 for(i=0; i<c->filter_length; i++){
263 val += src[sample_index + i] * (FELEM2)filter[i];
264 }
265 }
266
267 #ifdef CONFIG_RESAMPLE_AUDIOPHILE_KIDDY_MODE
268 dst[dst_index] = av_clip_int16(lrintf(val));
269 #else
270 val = (val + (1<<(FILTER_SHIFT-1)))>>FILTER_SHIFT;
271 dst[dst_index] = (unsigned)(val + 32768) > 65535 ? (val>>31) ^ 32767 : val;
272 #endif
273
274 frac += dst_incr_frac;
275 index += dst_incr;
276 if(frac >= c->src_incr){
277 frac -= c->src_incr;
278 index++;
279 }
280
281 if(dst_index + 1 == compensation_distance){
282 compensation_distance= 0;
283 dst_incr_frac= c->ideal_dst_incr % c->src_incr;
284 dst_incr= c->ideal_dst_incr / c->src_incr;
285 }
286 }
287 }
288 *consumed= FFMAX(index, 0) >> c->phase_shift;
289 if(index>=0) index &= c->phase_mask;
290
291 if(compensation_distance){
292 compensation_distance -= dst_index;
293 assert(compensation_distance > 0);
294 }
295 if(update_ctx){
296 c->frac= frac;
297 c->index= index;
298 c->dst_incr= dst_incr_frac + c->src_incr*dst_incr;
299 c->compensation_distance= compensation_distance;
300 }
301 #if 0
302 if(update_ctx && !c->compensation_distance){
303 #undef rand
304 av_resample_compensate(c, rand() % (8000*2) - 8000, 8000*2);
305 av_log(NULL, AV_LOG_DEBUG, "%d %d %d\n", c->dst_incr, c->ideal_dst_incr, c->compensation_distance);
306 }
307 #endif
308
309 return dst_index;
310 }