FFmpeg  4.0
af_resample.c
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1 /*
2  * This file is part of FFmpeg.
3  *
4  * FFmpeg is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU Lesser General Public
6  * License as published by the Free Software Foundation; either
7  * version 2.1 of the License, or (at your option) any later version.
8  *
9  * FFmpeg is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * Lesser General Public License for more details.
13  *
14  * You should have received a copy of the GNU Lesser General Public
15  * License along with FFmpeg; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17  */
18 
19 /**
20  * @file
21  * sample format and channel layout conversion audio filter
22  */
23 
24 #include "libavutil/avassert.h"
25 #include "libavutil/avstring.h"
26 #include "libavutil/common.h"
27 #include "libavutil/dict.h"
28 #include "libavutil/mathematics.h"
29 #include "libavutil/opt.h"
30 
32 
33 #include "audio.h"
34 #include "avfilter.h"
35 #include "formats.h"
36 #include "internal.h"
37 
38 typedef struct ResampleContext {
39  const AVClass *class;
42 
44  int64_t next_pts;
45  int64_t next_in_pts;
46 
47  /* set by filter_frame() to signal an output frame to request_frame() */
50 
52 {
53  ResampleContext *s = ctx->priv;
54  const AVClass *avr_class = avresample_get_class();
56 
57  while ((e = av_dict_get(*opts, "", e, AV_DICT_IGNORE_SUFFIX))) {
58  if (av_opt_find(&avr_class, e->key, NULL, 0,
60  av_dict_set(&s->options, e->key, e->value, 0);
61  }
62 
63  e = NULL;
64  while ((e = av_dict_get(s->options, "", e, AV_DICT_IGNORE_SUFFIX)))
65  av_dict_set(opts, e->key, NULL, 0);
66 
67  /* do not allow the user to override basic format options */
68  av_dict_set(&s->options, "in_channel_layout", NULL, 0);
69  av_dict_set(&s->options, "out_channel_layout", NULL, 0);
70  av_dict_set(&s->options, "in_sample_fmt", NULL, 0);
71  av_dict_set(&s->options, "out_sample_fmt", NULL, 0);
72  av_dict_set(&s->options, "in_sample_rate", NULL, 0);
73  av_dict_set(&s->options, "out_sample_rate", NULL, 0);
74 
75  return 0;
76 }
77 
79 {
80  ResampleContext *s = ctx->priv;
81 
82  if (s->avr) {
84  avresample_free(&s->avr);
85  }
86  av_dict_free(&s->options);
87 }
88 
90 {
91  AVFilterLink *inlink = ctx->inputs[0];
92  AVFilterLink *outlink = ctx->outputs[0];
93  AVFilterFormats *in_formats, *out_formats, *in_samplerates, *out_samplerates;
94  AVFilterChannelLayouts *in_layouts, *out_layouts;
95  int ret;
96 
97  if (!(in_formats = ff_all_formats (AVMEDIA_TYPE_AUDIO)) ||
98  !(out_formats = ff_all_formats (AVMEDIA_TYPE_AUDIO)) ||
99  !(in_samplerates = ff_all_samplerates ( )) ||
100  !(out_samplerates = ff_all_samplerates ( )) ||
101  !(in_layouts = ff_all_channel_layouts ( )) ||
102  !(out_layouts = ff_all_channel_layouts ( )))
103  return AVERROR(ENOMEM);
104 
105  if ((ret = ff_formats_ref (in_formats, &inlink->out_formats )) < 0 ||
106  (ret = ff_formats_ref (out_formats, &outlink->in_formats )) < 0 ||
107  (ret = ff_formats_ref (in_samplerates, &inlink->out_samplerates )) < 0 ||
108  (ret = ff_formats_ref (out_samplerates, &outlink->in_samplerates )) < 0 ||
109  (ret = ff_channel_layouts_ref (in_layouts, &inlink->out_channel_layouts)) < 0 ||
110  (ret = ff_channel_layouts_ref (out_layouts, &outlink->in_channel_layouts)) < 0)
111  return ret;
112 
113  return 0;
114 }
115 
116 static int config_output(AVFilterLink *outlink)
117 {
118  AVFilterContext *ctx = outlink->src;
119  AVFilterLink *inlink = ctx->inputs[0];
120  ResampleContext *s = ctx->priv;
121  char buf1[64], buf2[64];
122  int ret;
123 
124  int64_t resampling_forced;
125 
126  if (s->avr) {
127  avresample_close(s->avr);
128  avresample_free(&s->avr);
129  }
130 
131  if (inlink->channel_layout == outlink->channel_layout &&
132  inlink->sample_rate == outlink->sample_rate &&
133  (inlink->format == outlink->format ||
136  av_get_planar_sample_fmt(inlink->format) ==
137  av_get_planar_sample_fmt(outlink->format))))
138  return 0;
139 
140  if (!(s->avr = avresample_alloc_context()))
141  return AVERROR(ENOMEM);
142 
143  if (s->options) {
144  int ret;
145  AVDictionaryEntry *e = NULL;
146  while ((e = av_dict_get(s->options, "", e, AV_DICT_IGNORE_SUFFIX)))
147  av_log(ctx, AV_LOG_VERBOSE, "lavr option: %s=%s\n", e->key, e->value);
148 
149  ret = av_opt_set_dict(s->avr, &s->options);
150  if (ret < 0)
151  return ret;
152  }
153 
154  av_opt_set_int(s->avr, "in_channel_layout", inlink ->channel_layout, 0);
155  av_opt_set_int(s->avr, "out_channel_layout", outlink->channel_layout, 0);
156  av_opt_set_int(s->avr, "in_sample_fmt", inlink ->format, 0);
157  av_opt_set_int(s->avr, "out_sample_fmt", outlink->format, 0);
158  av_opt_set_int(s->avr, "in_sample_rate", inlink ->sample_rate, 0);
159  av_opt_set_int(s->avr, "out_sample_rate", outlink->sample_rate, 0);
160 
161  if ((ret = avresample_open(s->avr)) < 0)
162  return ret;
163 
164  av_opt_get_int(s->avr, "force_resampling", 0, &resampling_forced);
165  s->resampling = resampling_forced || (inlink->sample_rate != outlink->sample_rate);
166 
167  if (s->resampling) {
168  outlink->time_base = (AVRational){ 1, outlink->sample_rate };
171  } else
172  outlink->time_base = inlink->time_base;
173 
174  av_get_channel_layout_string(buf1, sizeof(buf1),
175  -1, inlink ->channel_layout);
176  av_get_channel_layout_string(buf2, sizeof(buf2),
177  -1, outlink->channel_layout);
178  av_log(ctx, AV_LOG_VERBOSE,
179  "fmt:%s srate:%d cl:%s -> fmt:%s srate:%d cl:%s\n",
180  av_get_sample_fmt_name(inlink ->format), inlink ->sample_rate, buf1,
181  av_get_sample_fmt_name(outlink->format), outlink->sample_rate, buf2);
182 
183  return 0;
184 }
185 
186 static int request_frame(AVFilterLink *outlink)
187 {
188  AVFilterContext *ctx = outlink->src;
189  ResampleContext *s = ctx->priv;
190  int ret = 0;
191 
192  s->got_output = 0;
193  while (ret >= 0 && !s->got_output)
194  ret = ff_request_frame(ctx->inputs[0]);
195 
196  /* flush the lavr delay buffer */
197  if (ret == AVERROR_EOF && s->avr) {
198  AVFrame *frame;
199  int nb_samples = avresample_get_out_samples(s->avr, 0);
200 
201  if (!nb_samples)
202  return ret;
203 
204  frame = ff_get_audio_buffer(outlink, nb_samples);
205  if (!frame)
206  return AVERROR(ENOMEM);
207 
208  ret = avresample_convert(s->avr, frame->extended_data,
209  frame->linesize[0], nb_samples,
210  NULL, 0, 0);
211  if (ret <= 0) {
212  av_frame_free(&frame);
213  return (ret == 0) ? AVERROR_EOF : ret;
214  }
215 
216  frame->nb_samples = ret;
217  frame->pts = s->next_pts;
218  return ff_filter_frame(outlink, frame);
219  }
220  return ret;
221 }
222 
223 static int filter_frame(AVFilterLink *inlink, AVFrame *in)
224 {
225  AVFilterContext *ctx = inlink->dst;
226  ResampleContext *s = ctx->priv;
227  AVFilterLink *outlink = ctx->outputs[0];
228  int ret;
229 
230  if (s->avr) {
231  AVFrame *out;
232  int delay, nb_samples;
233 
234  /* maximum possible samples lavr can output */
235  delay = avresample_get_delay(s->avr);
236  nb_samples = avresample_get_out_samples(s->avr, in->nb_samples);
237 
238  out = ff_get_audio_buffer(outlink, nb_samples);
239  if (!out) {
240  ret = AVERROR(ENOMEM);
241  goto fail;
242  }
243 
244  ret = avresample_convert(s->avr, out->extended_data, out->linesize[0],
245  nb_samples, in->extended_data, in->linesize[0],
246  in->nb_samples);
247  if (ret <= 0) {
248  av_frame_free(&out);
249  if (ret < 0)
250  goto fail;
251  }
252 
254 
255  if (s->resampling && s->next_pts == AV_NOPTS_VALUE) {
256  if (in->pts == AV_NOPTS_VALUE) {
257  av_log(ctx, AV_LOG_WARNING, "First timestamp is missing, "
258  "assuming 0.\n");
259  s->next_pts = 0;
260  } else
261  s->next_pts = av_rescale_q(in->pts, inlink->time_base,
262  outlink->time_base);
263  }
264 
265  if (ret > 0) {
266  out->nb_samples = ret;
267 
268  ret = av_frame_copy_props(out, in);
269  if (ret < 0) {
270  av_frame_free(&out);
271  goto fail;
272  }
273 
274  if (s->resampling) {
275  out->sample_rate = outlink->sample_rate;
276  /* Only convert in->pts if there is a discontinuous jump.
277  This ensures that out->pts tracks the number of samples actually
278  output by the resampler in the absence of such a jump.
279  Otherwise, the rounding in av_rescale_q() and av_rescale()
280  causes off-by-1 errors. */
281  if (in->pts != AV_NOPTS_VALUE && in->pts != s->next_in_pts) {
282  out->pts = av_rescale_q(in->pts, inlink->time_base,
283  outlink->time_base) -
284  av_rescale(delay, outlink->sample_rate,
285  inlink->sample_rate);
286  } else
287  out->pts = s->next_pts;
288 
289  s->next_pts = out->pts + out->nb_samples;
290  s->next_in_pts = in->pts + in->nb_samples;
291  } else
292  out->pts = in->pts;
293 
294  ret = ff_filter_frame(outlink, out);
295  s->got_output = 1;
296  }
297 
298 fail:
299  av_frame_free(&in);
300  } else {
301  in->format = outlink->format;
302  ret = ff_filter_frame(outlink, in);
303  s->got_output = 1;
304  }
305 
306  return ret;
307 }
308 
309 static const AVClass *resample_child_class_next(const AVClass *prev)
310 {
311  return prev ? NULL : avresample_get_class();
312 }
313 
314 static void *resample_child_next(void *obj, void *prev)
315 {
316  ResampleContext *s = obj;
317  return prev ? NULL : s->avr;
318 }
319 
320 static const AVClass resample_class = {
321  .class_name = "resample",
322  .item_name = av_default_item_name,
323  .version = LIBAVUTIL_VERSION_INT,
324  .child_class_next = resample_child_class_next,
326 };
327 
329  {
330  .name = "default",
331  .type = AVMEDIA_TYPE_AUDIO,
332  .filter_frame = filter_frame,
333  },
334  { NULL }
335 };
336 
338  {
339  .name = "default",
340  .type = AVMEDIA_TYPE_AUDIO,
341  .config_props = config_output,
342  .request_frame = request_frame
343  },
344  { NULL }
345 };
346 
348  .name = "resample",
349  .description = NULL_IF_CONFIG_SMALL("Audio resampling and conversion."),
350  .priv_size = sizeof(ResampleContext),
351  .priv_class = &resample_class,
352  .init_dict = init,
353  .uninit = uninit,
355  .inputs = avfilter_af_resample_inputs,
356  .outputs = avfilter_af_resample_outputs,
357 };
#define NULL
Definition: coverity.c:32
const char * s
Definition: avisynth_c.h:768
static const AVFilterPad avfilter_af_resample_outputs[]
Definition: af_resample.c:337
This structure describes decoded (raw) audio or video data.
Definition: frame.h:218
attribute_deprecated int avresample_open(AVAudioResampleContext *avr)
Definition: utils.c:36
attribute_deprecated int avresample_get_delay(AVAudioResampleContext *avr)
Definition: resample.c:438
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
Main libavfilter public API header.
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:191
attribute_deprecated int avresample_convert(AVAudioResampleContext *avr, uint8_t **output, int out_plane_size, int out_samples, uint8_t *const *input, int in_plane_size, int in_samples)
Definition: utils.c:330
int av_get_channel_layout_nb_channels(uint64_t channel_layout)
Return the number of channels in the channel layout.
const char * name
Pad name.
Definition: internal.h:60
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:72
AVFilterLink ** inputs
array of pointers to input links
Definition: avfilter.h:346
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
Public dictionary API.
int ff_channel_layouts_ref(AVFilterChannelLayouts *f, AVFilterChannelLayouts **ref)
Add *ref as a new reference to f.
Definition: formats.c:435
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1080
enum AVSampleFormat format
Definition: resample.h:48
#define av_cold
Definition: attributes.h:82
AVAudioResampleContext * avr
Definition: af_resample.c:40
AVOptions.
int64_t pts
Presentation timestamp in time_base units (time when frame should be shown to user).
Definition: frame.h:311
static AVFrame * frame
AVDictionaryEntry * av_dict_get(const AVDictionary *m, const char *key, const AVDictionaryEntry *prev, int flags)
Get a dictionary entry with matching key.
Definition: dict.c:40
#define AVERROR_EOF
End of file.
Definition: error.h:55
#define AV_LOG_VERBOSE
Detailed information.
Definition: log.h:192
enum AVSampleFormat av_get_planar_sample_fmt(enum AVSampleFormat sample_fmt)
Get the planar alternative form of the given sample format.
Definition: samplefmt.c:84
attribute_deprecated int avresample_get_out_samples(AVAudioResampleContext *avr, int in_nb_samples)
Definition: utils.c:753
#define av_log(a,...)
static av_cold void uninit(AVFilterContext *ctx)
Definition: af_resample.c:78
attribute_deprecated void avresample_close(AVAudioResampleContext *avr)
Definition: utils.c:262
AVFilterFormats * ff_all_formats(enum AVMediaType type)
Return a list of all formats supported by FFmpeg for the given media type.
Definition: formats.c:350
static int config_output(AVFilterLink *outlink)
Definition: af_resample.c:116
A filter pad used for either input or output.
Definition: internal.h:54
int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq)
Rescale a 64-bit integer by 2 rational numbers.
Definition: mathematics.c:142
void *(* child_next)(void *obj, void *prev)
Return next AVOptions-enabled child or NULL.
Definition: log.h:113
static av_cold int init(AVFilterContext *ctx, AVDictionary **opts)
Definition: af_resample.c:51
AVFrame * ff_get_audio_buffer(AVFilterLink *link, int nb_samples)
Request an audio samples buffer with a specific set of permissions.
Definition: audio.c:86
#define AVERROR(e)
Definition: error.h:43
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:202
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
void * priv
private data for use by the filter
Definition: avfilter.h:353
void av_dict_free(AVDictionary **pm)
Free all the memory allocated for an AVDictionary struct and all keys and values. ...
Definition: dict.c:203
int av_opt_set_int(void *obj, const char *name, int64_t val, int search_flags)
Definition: opt.c:558
simple assert() macros that are a bit more flexible than ISO C assert().
AVDictionary * options
Definition: af_resample.c:41
const char * av_get_sample_fmt_name(enum AVSampleFormat sample_fmt)
Return the name of sample_fmt, or NULL if sample_fmt is not recognized.
Definition: samplefmt.c:49
AVFilter ff_af_resample
Definition: af_resample.c:347
#define fail()
Definition: checkasm.h:116
attribute_deprecated int avresample_available(AVAudioResampleContext *avr)
Definition: utils.c:748
const AVOption * av_opt_find(void *obj, const char *name, const char *unit, int opt_flags, int search_flags)
Look for an option in an object.
Definition: opt.c:1595
AVDictionary * opts
Definition: movenc.c:50
static const AVClass resample_class
Definition: af_resample.c:320
int64_t av_rescale(int64_t a, int64_t b, int64_t c)
Rescale a 64-bit integer with rounding to nearest.
Definition: mathematics.c:129
external API header
static void * resample_child_next(void *obj, void *prev)
Definition: af_resample.c:314
#define AV_OPT_SEARCH_CHILDREN
Search in possible children of the given object first.
Definition: opt.h:555
int ff_formats_ref(AVFilterFormats *f, AVFilterFormats **ref)
Add *ref as a new reference to formats.
Definition: formats.c:440
static av_cold int init_dict(AVFilterContext *ctx, AVDictionary **opts)
Definition: af_aresample.c:46
AVFormatContext * ctx
Definition: movenc.c:48
static const AVFilterPad inputs[]
Definition: af_acontrast.c:193
AVFilterChannelLayouts * ff_all_channel_layouts(void)
Construct an empty AVFilterChannelLayouts/AVFilterFormats struct – representing any channel layout (...
Definition: formats.c:401
static const AVFilterPad outputs[]
Definition: af_acontrast.c:203
A list of supported channel layouts.
Definition: formats.h:85
attribute_deprecated const AVClass * avresample_get_class(void)
Definition: options.c:110
void av_get_channel_layout_string(char *buf, int buf_size, int nb_channels, uint64_t channel_layout)
Return a description of a channel layout.
int format
format of the frame, -1 if unknown or unset Values correspond to enum AVPixelFormat for video frames...
Definition: frame.h:291
int av_opt_get_int(void *obj, const char *name, int search_flags, int64_t *out_val)
Definition: opt.c:875
sample_rate
int av_opt_set_dict(void *obj, AVDictionary **options)
Set all the options from a given dictionary on an object.
Definition: opt.c:1590
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:249
int av_dict_set(AVDictionary **pm, const char *key, const char *value, int flags)
Set the given entry in *pm, overwriting an existing entry.
Definition: dict.c:70
uint8_t pi<< 24) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_U8, uint8_t,(*(const uint8_t *) pi - 0x80) *(1.0f/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_U8, uint8_t,(*(const uint8_t *) pi - 0x80) *(1.0/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S16, int16_t,(*(const int16_t *) pi >> 8)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S16, int16_t, *(const int16_t *) pi *(1.0f/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S16, int16_t, *(const int16_t *) pi *(1.0/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S32, int32_t,(*(const int32_t *) pi >> 24)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S32, int32_t, *(const int32_t *) pi *(1.0f/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S32, int32_t, *(const int32_t *) pi *(1.0/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_FLT, float, av_clip_uint8(lrintf(*(const float *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_FLT, float, av_clip_int16(lrintf(*(const float *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_FLT, float, av_clipl_int32(llrintf(*(const float *) pi *(1U<< 31)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_DBL, double, av_clip_uint8(lrint(*(const double *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_DBL, double, av_clip_int16(lrint(*(const double *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_DBL, double, av_clipl_int32(llrint(*(const double *) pi *(1U<< 31)))) #define SET_CONV_FUNC_GROUP(ofmt, ifmt) static void set_generic_function(AudioConvert *ac) { } void ff_audio_convert_free(AudioConvert **ac) { if(! *ac) return;ff_dither_free(&(*ac) ->dc);av_freep(ac);} AudioConvert *ff_audio_convert_alloc(AVAudioResampleContext *avr, enum AVSampleFormat out_fmt, enum AVSampleFormat in_fmt, int channels, int sample_rate, int apply_map) { AudioConvert *ac;int in_planar, out_planar;ac=av_mallocz(sizeof(*ac));if(!ac) return NULL;ac->avr=avr;ac->out_fmt=out_fmt;ac->in_fmt=in_fmt;ac->channels=channels;ac->apply_map=apply_map;if(avr->dither_method !=AV_RESAMPLE_DITHER_NONE &&av_get_packed_sample_fmt(out_fmt)==AV_SAMPLE_FMT_S16 &&av_get_bytes_per_sample(in_fmt) > 2) { ac->dc=ff_dither_alloc(avr, out_fmt, in_fmt, channels, sample_rate, apply_map);if(!ac->dc) { av_free(ac);return NULL;} return ac;} in_planar=ff_sample_fmt_is_planar(in_fmt, channels);out_planar=ff_sample_fmt_is_planar(out_fmt, channels);if(in_planar==out_planar) { ac->func_type=CONV_FUNC_TYPE_FLAT;ac->planes=in_planar ? ac->channels :1;} else if(in_planar) ac->func_type=CONV_FUNC_TYPE_INTERLEAVE;else ac->func_type=CONV_FUNC_TYPE_DEINTERLEAVE;set_generic_function(ac);if(ARCH_AARCH64) ff_audio_convert_init_aarch64(ac);if(ARCH_ARM) ff_audio_convert_init_arm(ac);if(ARCH_X86) ff_audio_convert_init_x86(ac);return ac;} int ff_audio_convert(AudioConvert *ac, AudioData *out, AudioData *in) { int use_generic=1;int len=in->nb_samples;int p;if(ac->dc) { av_log(ac->avr, AV_LOG_TRACE, "%d samples - audio_convert: %s to %s (dithered)\", len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt));return ff_convert_dither(ac-> in
Describe the class of an AVClass context structure.
Definition: log.h:67
int sample_rate
Sample rate of the audio data.
Definition: frame.h:391
Filter definition.
Definition: avfilter.h:144
Rational number (pair of numerator and denominator).
Definition: rational.h:58
const char * name
Filter name.
Definition: avfilter.h:148
static int filter_frame(AVFilterLink *inlink, AVFrame *in)
Definition: af_resample.c:223
AVFilterLink ** outputs
array of pointers to output links
Definition: avfilter.h:350
AVFilterFormats * ff_all_samplerates(void)
Definition: formats.c:395
static int request_frame(AVFilterLink *outlink)
Definition: af_resample.c:186
attribute_deprecated AVAudioResampleContext * avresample_alloc_context(void)
Definition: options.c:96
static int query_formats(AVFilterContext *ctx)
Definition: af_resample.c:89
common internal and external API header
int64_t next_in_pts
Definition: af_resample.c:45
#define AV_OPT_SEARCH_FAKE_OBJ
The obj passed to av_opt_find() is fake – only a double pointer to AVClass instead of a required poi...
Definition: opt.h:564
char * key
Definition: dict.h:86
char * value
Definition: dict.h:87
attribute_deprecated void avresample_free(AVAudioResampleContext **avr)
Definition: utils.c:278
A list of supported formats for one end of a filter link.
Definition: formats.h:64
An instance of a filter.
Definition: avfilter.h:338
FILE * out
Definition: movenc.c:54
#define AV_DICT_IGNORE_SUFFIX
Return first entry in a dictionary whose first part corresponds to the search key, ignoring the suffix of the found key string.
Definition: dict.h:70
static const AVClass * resample_child_class_next(const AVClass *prev)
Definition: af_resample.c:309
static const AVFilterPad avfilter_af_resample_inputs[]
Definition: af_resample.c:328
int ff_request_frame(AVFilterLink *link)
Request an input frame from the filter at the other end of the link.
Definition: avfilter.c:407
internal API functions
uint8_t ** extended_data
pointers to the data planes/channels.
Definition: frame.h:265
int nb_samples
number of audio samples (per channel) described by this frame
Definition: frame.h:284
int av_frame_copy_props(AVFrame *dst, const AVFrame *src)
Copy only "metadata" fields from src to dst.
Definition: frame.c:652
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248
int64_t next_pts
Definition: af_resample.c:44