FFmpeg
af_afreqshift.c
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1 /*
2  * Copyright (c) Paul B Mahol
3  * Copyright (c) Laurent de Soras, 2005
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 
23 #include "libavutil/ffmath.h"
24 #include "libavutil/opt.h"
25 #include "avfilter.h"
26 #include "audio.h"
27 #include "formats.h"
28 
29 #define MAX_NB_COEFFS 16
30 
31 typedef struct AFreqShift {
32  const AVClass *class;
33 
34  double shift;
35  double level;
36  int nb_coeffs;
38 
39  double cd[MAX_NB_COEFFS * 2];
40  float cf[MAX_NB_COEFFS * 2];
41 
42  int64_t in_samples;
43 
46 
48  int channel,
49  AVFrame *in, AVFrame *out);
50 } AFreqShift;
51 
52 static const enum AVSampleFormat sample_fmts[] = {
54 };
55 
56 #define PFILTER(name, type, sin, cos, cc) \
57 static void pfilter_channel_## name(AVFilterContext *ctx, \
58  int ch, \
59  AVFrame *in, AVFrame *out) \
60 { \
61  AFreqShift *s = ctx->priv; \
62  const int nb_samples = in->nb_samples; \
63  const type *src = (const type *)in->extended_data[ch]; \
64  type *dst = (type *)out->extended_data[ch]; \
65  type *i1 = (type *)s->i1->extended_data[ch]; \
66  type *o1 = (type *)s->o1->extended_data[ch]; \
67  type *i2 = (type *)s->i2->extended_data[ch]; \
68  type *o2 = (type *)s->o2->extended_data[ch]; \
69  const type *c = s->cc; \
70  const type level = s->level; \
71  type shift = s->shift * M_PI; \
72  type cos_theta = cos(shift); \
73  type sin_theta = sin(shift); \
74  \
75  for (int n = 0; n < nb_samples; n++) { \
76  type xn1 = src[n], xn2 = src[n]; \
77  type I, Q; \
78  \
79  for (int j = 0; j < s->nb_coeffs; j++) { \
80  I = c[j] * (xn1 + o2[j]) - i2[j]; \
81  i2[j] = i1[j]; \
82  i1[j] = xn1; \
83  o2[j] = o1[j]; \
84  o1[j] = I; \
85  xn1 = I; \
86  } \
87  \
88  for (int j = s->nb_coeffs; j < s->nb_coeffs*2; j++) { \
89  Q = c[j] * (xn2 + o2[j]) - i2[j]; \
90  i2[j] = i1[j]; \
91  i1[j] = xn2; \
92  o2[j] = o1[j]; \
93  o1[j] = Q; \
94  xn2 = Q; \
95  } \
96  Q = o2[s->nb_coeffs * 2 - 1]; \
97  \
98  dst[n] = (I * cos_theta - Q * sin_theta) * level; \
99  } \
100 }
101 
102 PFILTER(flt, float, sin, cos, cf)
103 PFILTER(dbl, double, sin, cos, cd)
104 
105 #define FFILTER(name, type, sin, cos, fmod, cc) \
106 static void ffilter_channel_## name(AVFilterContext *ctx, \
107  int ch, \
108  AVFrame *in, AVFrame *out) \
109 { \
110  AFreqShift *s = ctx->priv; \
111  const int nb_samples = in->nb_samples; \
112  const type *src = (const type *)in->extended_data[ch]; \
113  type *dst = (type *)out->extended_data[ch]; \
114  type *i1 = (type *)s->i1->extended_data[ch]; \
115  type *o1 = (type *)s->o1->extended_data[ch]; \
116  type *i2 = (type *)s->i2->extended_data[ch]; \
117  type *o2 = (type *)s->o2->extended_data[ch]; \
118  const type *c = s->cc; \
119  const type level = s->level; \
120  type ts = 1. / in->sample_rate; \
121  type shift = s->shift; \
122  int64_t N = s->in_samples; \
123  \
124  for (int n = 0; n < nb_samples; n++) { \
125  type xn1 = src[n], xn2 = src[n]; \
126  type I, Q, theta; \
127  \
128  for (int j = 0; j < s->nb_coeffs; j++) { \
129  I = c[j] * (xn1 + o2[j]) - i2[j]; \
130  i2[j] = i1[j]; \
131  i1[j] = xn1; \
132  o2[j] = o1[j]; \
133  o1[j] = I; \
134  xn1 = I; \
135  } \
136  \
137  for (int j = s->nb_coeffs; j < s->nb_coeffs*2; j++) { \
138  Q = c[j] * (xn2 + o2[j]) - i2[j]; \
139  i2[j] = i1[j]; \
140  i1[j] = xn2; \
141  o2[j] = o1[j]; \
142  o1[j] = Q; \
143  xn2 = Q; \
144  } \
145  Q = o2[s->nb_coeffs * 2 - 1]; \
146  \
147  theta = 2. * M_PI * fmod(shift * (N + n) * ts, 1.); \
148  dst[n] = (I * cos(theta) - Q * sin(theta)) * level; \
149  } \
150 }
151 
152 FFILTER(flt, float, sinf, cosf, fmodf, cf)
153 FFILTER(dbl, double, sin, cos, fmod, cd)
154 
155 static void compute_transition_param(double *K, double *Q, double transition)
156 {
157  double kksqrt, e, e2, e4, k, q;
158 
159  k = tan((1. - transition * 2.) * M_PI / 4.);
160  k *= k;
161  kksqrt = pow(1 - k * k, 0.25);
162  e = 0.5 * (1. - kksqrt) / (1. + kksqrt);
163  e2 = e * e;
164  e4 = e2 * e2;
165  q = e * (1. + e4 * (2. + e4 * (15. + 150. * e4)));
166 
167  *Q = q;
168  *K = k;
169 }
170 
171 static double ipowp(double x, int64_t n)
172 {
173  double z = 1.;
174 
175  while (n != 0) {
176  if (n & 1)
177  z *= x;
178  n >>= 1;
179  x *= x;
180  }
181 
182  return z;
183 }
184 
185 static double compute_acc_num(double q, int order, int c)
186 {
187  int64_t i = 0;
188  int j = 1;
189  double acc = 0.;
190  double q_ii1;
191 
192  do {
193  q_ii1 = ipowp(q, i * (i + 1));
194  q_ii1 *= sin((i * 2 + 1) * c * M_PI / order) * j;
195  acc += q_ii1;
196 
197  j = -j;
198  i++;
199  } while (fabs(q_ii1) > 1e-100);
200 
201  return acc;
202 }
203 
204 static double compute_acc_den(double q, int order, int c)
205 {
206  int64_t i = 1;
207  int j = -1;
208  double acc = 0.;
209  double q_i2;
210 
211  do {
212  q_i2 = ipowp(q, i * i);
213  q_i2 *= cos(i * 2 * c * M_PI / order) * j;
214  acc += q_i2;
215 
216  j = -j;
217  i++;
218  } while (fabs(q_i2) > 1e-100);
219 
220  return acc;
221 }
222 
223 static double compute_coef(int index, double k, double q, int order)
224 {
225  const int c = index + 1;
226  const double num = compute_acc_num(q, order, c) * pow(q, 0.25);
227  const double den = compute_acc_den(q, order, c) + 0.5;
228  const double ww = num / den;
229  const double wwsq = ww * ww;
230 
231  const double x = sqrt((1 - wwsq * k) * (1 - wwsq / k)) / (1 + wwsq);
232  const double coef = (1 - x) / (1 + x);
233 
234  return coef;
235 }
236 
237 static void compute_coefs(double *coef_arrd, float *coef_arrf, int nbr_coefs, double transition)
238 {
239  const int order = nbr_coefs * 2 + 1;
240  double k, q;
241 
242  compute_transition_param(&k, &q, transition);
243 
244  for (int n = 0; n < nbr_coefs; n++) {
245  const int idx = (n / 2) + (n & 1) * nbr_coefs / 2;
246 
247  coef_arrd[idx] = compute_coef(n, k, q, order);
248  coef_arrf[idx] = coef_arrd[idx];
249  }
250 }
251 
253 {
254  AVFilterContext *ctx = inlink->dst;
255  AFreqShift *s = ctx->priv;
256 
257  if (s->old_nb_coeffs != s->nb_coeffs)
258  compute_coefs(s->cd, s->cf, s->nb_coeffs * 2, 2. * 20. / inlink->sample_rate);
259  s->old_nb_coeffs = s->nb_coeffs;
260 
265  if (!s->i1 || !s->o1 || !s->i2 || !s->o2)
266  return AVERROR(ENOMEM);
267 
268  if (inlink->format == AV_SAMPLE_FMT_DBLP) {
269  if (!strcmp(ctx->filter->name, "afreqshift"))
270  s->filter_channel = ffilter_channel_dbl;
271  else
272  s->filter_channel = pfilter_channel_dbl;
273  } else {
274  if (!strcmp(ctx->filter->name, "afreqshift"))
275  s->filter_channel = ffilter_channel_flt;
276  else
277  s->filter_channel = pfilter_channel_flt;
278  }
279 
280  return 0;
281 }
282 
283 typedef struct ThreadData {
284  AVFrame *in, *out;
285 } ThreadData;
286 
287 static int filter_channels(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
288 {
289  AFreqShift *s = ctx->priv;
290  ThreadData *td = arg;
291  AVFrame *out = td->out;
292  AVFrame *in = td->in;
293  const int start = (in->channels * jobnr) / nb_jobs;
294  const int end = (in->channels * (jobnr+1)) / nb_jobs;
295 
296  for (int ch = start; ch < end; ch++)
297  s->filter_channel(ctx, ch, in, out);
298 
299  return 0;
300 }
301 
303 {
304  AVFilterContext *ctx = inlink->dst;
305  AVFilterLink *outlink = ctx->outputs[0];
306  AFreqShift *s = ctx->priv;
307  AVFrame *out;
308  ThreadData td;
309 
310  if (s->old_nb_coeffs != s->nb_coeffs)
311  compute_coefs(s->cd, s->cf, s->nb_coeffs * 2, 2. * 20. / inlink->sample_rate);
312  s->old_nb_coeffs = s->nb_coeffs;
313 
314  if (av_frame_is_writable(in)) {
315  out = in;
316  } else {
317  out = ff_get_audio_buffer(outlink, in->nb_samples);
318  if (!out) {
319  av_frame_free(&in);
320  return AVERROR(ENOMEM);
321  }
323  }
324 
325  td.in = in; td.out = out;
328 
329  s->in_samples += in->nb_samples;
330 
331  if (out != in)
332  av_frame_free(&in);
333  return ff_filter_frame(outlink, out);
334 }
335 
337 {
338  AFreqShift *s = ctx->priv;
339 
340  av_frame_free(&s->i1);
341  av_frame_free(&s->o1);
342  av_frame_free(&s->i2);
343  av_frame_free(&s->o2);
344 }
345 
346 #define OFFSET(x) offsetof(AFreqShift, x)
347 #define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_RUNTIME_PARAM
348 
349 static const AVOption afreqshift_options[] = {
350  { "shift", "set frequency shift", OFFSET(shift), AV_OPT_TYPE_DOUBLE, {.dbl=0}, -INT_MAX, INT_MAX, FLAGS },
351  { "level", "set output level", OFFSET(level), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0.0, 1.0, FLAGS },
352  { "order", "set filter order", OFFSET(nb_coeffs),AV_OPT_TYPE_INT, {.i64=8}, 1, MAX_NB_COEFFS, FLAGS },
353  { NULL }
354 };
355 
356 AVFILTER_DEFINE_CLASS(afreqshift);
357 
358 static const AVFilterPad inputs[] = {
359  {
360  .name = "default",
361  .type = AVMEDIA_TYPE_AUDIO,
362  .filter_frame = filter_frame,
363  .config_props = config_input,
364  },
365 };
366 
367 static const AVFilterPad outputs[] = {
368  {
369  .name = "default",
370  .type = AVMEDIA_TYPE_AUDIO,
371  },
372 };
373 
375  .name = "afreqshift",
376  .description = NULL_IF_CONFIG_SMALL("Apply frequency shifting to input audio."),
377  .priv_size = sizeof(AFreqShift),
378  .priv_class = &afreqshift_class,
379  .uninit = uninit,
383  .process_command = ff_filter_process_command,
386 };
387 
388 static const AVOption aphaseshift_options[] = {
389  { "shift", "set phase shift", OFFSET(shift), AV_OPT_TYPE_DOUBLE, {.dbl=0}, -1.0, 1.0, FLAGS },
390  { "level", "set output level",OFFSET(level), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0.0, 1.0, FLAGS },
391  { "order", "set filter order",OFFSET(nb_coeffs), AV_OPT_TYPE_INT,{.i64=8}, 1, MAX_NB_COEFFS, FLAGS },
392  { NULL }
393 };
394 
395 AVFILTER_DEFINE_CLASS(aphaseshift);
396 
398  .name = "aphaseshift",
399  .description = NULL_IF_CONFIG_SMALL("Apply phase shifting to input audio."),
400  .priv_size = sizeof(AFreqShift),
401  .priv_class = &aphaseshift_class,
402  .uninit = uninit,
406  .process_command = ff_filter_process_command,
409 };
ff_get_audio_buffer
AVFrame * ff_get_audio_buffer(AVFilterLink *link, int nb_samples)
Request an audio samples buffer with a specific set of permissions.
Definition: audio.c:88
AV_SAMPLE_FMT_FLTP
@ AV_SAMPLE_FMT_FLTP
float, planar
Definition: samplefmt.h:69
td
#define td
Definition: regdef.h:70
level
uint8_t level
Definition: svq3.c:204
acc
int acc
Definition: yuv2rgb.c:554
AVERROR
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
opt.h
out
FILE * out
Definition: movenc.c:54
ff_filter_frame
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1018
AFreqShift::old_nb_coeffs
int old_nb_coeffs
Definition: af_afreqshift.c:37
inlink
The exact code depends on how similar the blocks are and how related they are to the and needs to apply these operations to the correct inlink or outlink if there are several Macros are available to factor that when no extra processing is inlink
Definition: filter_design.txt:212
filter_channels
static int filter_channels(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
Definition: af_afreqshift.c:287
av_frame_free
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:112
inputs
static const AVFilterPad inputs[]
Definition: af_afreqshift.c:358
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:303
index
fg index
Definition: ffmpeg_filter.c:168
AVOption
AVOption.
Definition: opt.h:247
AFreqShift::cd
double cd[MAX_NB_COEFFS *2]
Definition: af_afreqshift.c:39
MAX_NB_COEFFS
#define MAX_NB_COEFFS
Definition: af_afreqshift.c:29
AVFilter::name
const char * name
Filter name.
Definition: avfilter.h:153
ThreadData::out
AVFrame * out
Definition: af_adeclick.c:473
formats.h
cosf
#define cosf(x)
Definition: libm.h:78
aphaseshift_options
static const AVOption aphaseshift_options[]
Definition: af_afreqshift.c:388
filter_frame
static int filter_frame(AVFilterLink *inlink, AVFrame *in)
Definition: af_afreqshift.c:302
ff_af_aphaseshift
const AVFilter ff_af_aphaseshift
Definition: af_afreqshift.c:397
AVFilterPad
A filter pad used for either input or output.
Definition: internal.h:50
av_cold
#define av_cold
Definition: attributes.h:90
compute_acc_den
static double compute_acc_den(double q, int order, int c)
Definition: af_afreqshift.c:204
AFreqShift::cf
float cf[MAX_NB_COEFFS *2]
Definition: af_afreqshift.c:40
PFILTER
#define PFILTER(name, type, sin, cos, cc)
Definition: af_afreqshift.c:56
s
#define s(width, name)
Definition: cbs_vp9.c:257
AFreqShift
Definition: af_afreqshift.c:31
sample_fmts
static enum AVSampleFormat sample_fmts[]
Definition: af_afreqshift.c:52
AVFrame::channels
int channels
number of audio channels, only used for audio.
Definition: frame.h:592
AV_OPT_TYPE_DOUBLE
@ AV_OPT_TYPE_DOUBLE
Definition: opt.h:226
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
ctx
AVFormatContext * ctx
Definition: movenc.c:48
FILTER_INPUTS
#define FILTER_INPUTS(array)
Definition: internal.h:191
arg
const char * arg
Definition: jacosubdec.c:67
compute_transition_param
static void compute_transition_param(double *K, double *Q, double transition)
Definition: af_afreqshift.c:155
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
fabs
static __device__ float fabs(float a)
Definition: cuda_runtime.h:182
NULL
#define NULL
Definition: coverity.c:32
av_frame_copy_props
int av_frame_copy_props(AVFrame *dst, const AVFrame *src)
Copy only "metadata" fields from src to dst.
Definition: frame.c:537
ipowp
static double ipowp(double x, int64_t n)
Definition: af_afreqshift.c:171
OFFSET
#define OFFSET(x)
Definition: af_afreqshift.c:346
AFreqShift::shift
double shift
Definition: af_afreqshift.c:34
sinf
#define sinf(x)
Definition: libm.h:419
AFreqShift::i2
AVFrame * i2
Definition: af_afreqshift.c:45
AFreqShift::level
double level
Definition: af_afreqshift.c:35
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
FFILTER
#define FFILTER(name, type, sin, cos, fmod, cc)
Definition: af_afreqshift.c:105
compute_acc_num
static double compute_acc_num(double q, int order, int c)
Definition: af_afreqshift.c:185
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
AV_SAMPLE_FMT_NONE
@ AV_SAMPLE_FMT_NONE
Definition: samplefmt.h:59
FILTER_SAMPLEFMTS_ARRAY
#define FILTER_SAMPLEFMTS_ARRAY(array)
Definition: internal.h:174
av_frame_is_writable
int av_frame_is_writable(AVFrame *frame)
Check if the frame data is writable.
Definition: frame.c:473
config_input
static int config_input(AVFilterLink *inlink)
Definition: af_afreqshift.c:252
ff_filter_process_command
int ff_filter_process_command(AVFilterContext *ctx, const char *cmd, const char *arg, char *res, int res_len, int flags)
Generic processing of user supplied commands that are set in the same way as the filter options.
Definition: avfilter.c:882
AFreqShift::nb_coeffs
int nb_coeffs
Definition: af_afreqshift.c:36
M_PI
#define M_PI
Definition: mathematics.h:52
uninit
static av_cold void uninit(AVFilterContext *ctx)
Definition: af_afreqshift.c:336
AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC
#define AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC
Some filters support a generic "enable" expression option that can be used to enable or disable a fil...
Definition: avfilter.h:130
AVFrame::nb_samples
int nb_samples
number of audio samples (per channel) described by this frame
Definition: frame.h:369
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:271
AFreqShift::o1
AVFrame * o1
Definition: af_afreqshift.c:44
ff_filter_get_nb_threads
int ff_filter_get_nb_threads(AVFilterContext *ctx)
Get number of threads for current filter instance.
Definition: avfilter.c:803
AVSampleFormat
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:58
ThreadData
Used for passing data between threads.
Definition: dsddec.c:67
AFreqShift::in_samples
int64_t in_samples
Definition: af_afreqshift.c:42
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
ff_af_afreqshift
const AVFilter ff_af_afreqshift
Definition: af_afreqshift.c:374
AVFilterPad::name
const char * name
Pad name.
Definition: internal.h:56
compute_coefs
static void compute_coefs(double *coef_arrd, float *coef_arrf, int nbr_coefs, double transition)
Definition: af_afreqshift.c:237
AVFilter
Filter definition.
Definition: avfilter.h:149
afreqshift_options
static const AVOption afreqshift_options[]
Definition: af_afreqshift.c:349
AFreqShift::filter_channel
void(* filter_channel)(AVFilterContext *ctx, int channel, AVFrame *in, AVFrame *out)
Definition: af_afreqshift.c:47
AFreqShift::o2
AVFrame * o2
Definition: af_afreqshift.c:45
outputs
static const AVFilterPad outputs[]
Definition: af_afreqshift.c:367
channel_layout.h
AV_OPT_TYPE_INT
@ AV_OPT_TYPE_INT
Definition: opt.h:224
avfilter.h
AV_SAMPLE_FMT_DBLP
@ AV_SAMPLE_FMT_DBLP
double, planar
Definition: samplefmt.h:70
ffmath.h
AVFilterContext
An instance of a filter.
Definition: avfilter.h:386
shift
static int shift(int a, int b)
Definition: sonic.c:83
AVFILTER_FLAG_SLICE_THREADS
#define AVFILTER_FLAG_SLICE_THREADS
The filter supports multithreading by splitting frames into multiple parts and processing them concur...
Definition: avfilter.h:121
audio.h
FLAGS
#define FLAGS
Definition: af_afreqshift.c:347
ThreadData::in
AVFrame * in
Definition: af_adecorrelate.c:154
FILTER_OUTPUTS
#define FILTER_OUTPUTS(array)
Definition: internal.h:192
ff_filter_execute
static av_always_inline int ff_filter_execute(AVFilterContext *ctx, avfilter_action_func *func, void *arg, int *ret, int nb_jobs)
Definition: internal.h:143
AVFILTER_DEFINE_CLASS
AVFILTER_DEFINE_CLASS(afreqshift)
compute_coef
static double compute_coef(int index, double k, double q, int order)
Definition: af_afreqshift.c:223
channel
channel
Definition: ebur128.h:39
AFreqShift::i1
AVFrame * i1
Definition: af_afreqshift.c:44