FFmpeg  2.1.1
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 
31 #include "libavresample/avresample.h"
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 
43  int64_t next_pts;
44 
45  /* set by filter_frame() to signal an output frame to request_frame() */
48 
49 static av_cold int init(AVFilterContext *ctx, AVDictionary **opts)
50 {
51  ResampleContext *s = ctx->priv;
52  const AVClass *avr_class = avresample_get_class();
53  AVDictionaryEntry *e = NULL;
54 
55  while ((e = av_dict_get(*opts, "", e, AV_DICT_IGNORE_SUFFIX))) {
56  if (av_opt_find(&avr_class, e->key, NULL, 0,
58  av_dict_set(&s->options, e->key, e->value, 0);
59  }
60 
61  e = NULL;
62  while ((e = av_dict_get(s->options, "", e, AV_DICT_IGNORE_SUFFIX)))
63  av_dict_set(opts, e->key, NULL, 0);
64 
65  /* do not allow the user to override basic format options */
66  av_dict_set(&s->options, "in_channel_layout", NULL, 0);
67  av_dict_set(&s->options, "out_channel_layout", NULL, 0);
68  av_dict_set(&s->options, "in_sample_fmt", NULL, 0);
69  av_dict_set(&s->options, "out_sample_fmt", NULL, 0);
70  av_dict_set(&s->options, "in_sample_rate", NULL, 0);
71  av_dict_set(&s->options, "out_sample_rate", NULL, 0);
72 
73  return 0;
74 }
75 
76 static av_cold void uninit(AVFilterContext *ctx)
77 {
78  ResampleContext *s = ctx->priv;
79 
80  if (s->avr) {
82  avresample_free(&s->avr);
83  }
84  av_dict_free(&s->options);
85 }
86 
88 {
89  AVFilterLink *inlink = ctx->inputs[0];
90  AVFilterLink *outlink = ctx->outputs[0];
91 
94  AVFilterFormats *in_samplerates = ff_all_samplerates();
95  AVFilterFormats *out_samplerates = ff_all_samplerates();
98 
99  ff_formats_ref(in_formats, &inlink->out_formats);
100  ff_formats_ref(out_formats, &outlink->in_formats);
101 
102  ff_formats_ref(in_samplerates, &inlink->out_samplerates);
103  ff_formats_ref(out_samplerates, &outlink->in_samplerates);
104 
105  ff_channel_layouts_ref(in_layouts, &inlink->out_channel_layouts);
106  ff_channel_layouts_ref(out_layouts, &outlink->in_channel_layouts);
107 
108  return 0;
109 }
110 
111 static int config_output(AVFilterLink *outlink)
112 {
113  AVFilterContext *ctx = outlink->src;
114  AVFilterLink *inlink = ctx->inputs[0];
115  ResampleContext *s = ctx->priv;
116  char buf1[64], buf2[64];
117  int ret;
118 
119  if (s->avr) {
120  avresample_close(s->avr);
121  avresample_free(&s->avr);
122  }
123 
124  if (inlink->channel_layout == outlink->channel_layout &&
125  inlink->sample_rate == outlink->sample_rate &&
126  (inlink->format == outlink->format ||
129  av_get_planar_sample_fmt(inlink->format) ==
130  av_get_planar_sample_fmt(outlink->format))))
131  return 0;
132 
133  if (!(s->avr = avresample_alloc_context()))
134  return AVERROR(ENOMEM);
135 
136  if (s->options) {
137  AVDictionaryEntry *e = NULL;
138  while ((e = av_dict_get(s->options, "", e, AV_DICT_IGNORE_SUFFIX)))
139  av_log(ctx, AV_LOG_VERBOSE, "lavr option: %s=%s\n", e->key, e->value);
140 
141  av_opt_set_dict(s->avr, &s->options);
142  }
143 
144  av_opt_set_int(s->avr, "in_channel_layout", inlink ->channel_layout, 0);
145  av_opt_set_int(s->avr, "out_channel_layout", outlink->channel_layout, 0);
146  av_opt_set_int(s->avr, "in_sample_fmt", inlink ->format, 0);
147  av_opt_set_int(s->avr, "out_sample_fmt", outlink->format, 0);
148  av_opt_set_int(s->avr, "in_sample_rate", inlink ->sample_rate, 0);
149  av_opt_set_int(s->avr, "out_sample_rate", outlink->sample_rate, 0);
150 
151  if ((ret = avresample_open(s->avr)) < 0)
152  return ret;
153 
154  outlink->time_base = (AVRational){ 1, outlink->sample_rate };
156 
157  av_get_channel_layout_string(buf1, sizeof(buf1),
158  -1, inlink ->channel_layout);
159  av_get_channel_layout_string(buf2, sizeof(buf2),
160  -1, outlink->channel_layout);
161  av_log(ctx, AV_LOG_VERBOSE,
162  "fmt:%s srate:%d cl:%s -> fmt:%s srate:%d cl:%s\n",
163  av_get_sample_fmt_name(inlink ->format), inlink ->sample_rate, buf1,
164  av_get_sample_fmt_name(outlink->format), outlink->sample_rate, buf2);
165 
166  return 0;
167 }
168 
169 static int request_frame(AVFilterLink *outlink)
170 {
171  AVFilterContext *ctx = outlink->src;
172  ResampleContext *s = ctx->priv;
173  int ret = 0;
174 
175  s->got_output = 0;
176  while (ret >= 0 && !s->got_output)
177  ret = ff_request_frame(ctx->inputs[0]);
178 
179  /* flush the lavr delay buffer */
180  if (ret == AVERROR_EOF && s->avr) {
181  AVFrame *frame;
182  int nb_samples = av_rescale_rnd(avresample_get_delay(s->avr),
183  outlink->sample_rate,
184  ctx->inputs[0]->sample_rate,
185  AV_ROUND_UP);
186 
187  if (!nb_samples)
188  return ret;
189 
190  frame = ff_get_audio_buffer(outlink, nb_samples);
191  if (!frame)
192  return AVERROR(ENOMEM);
193 
194  ret = avresample_convert(s->avr, frame->extended_data,
195  frame->linesize[0], nb_samples,
196  NULL, 0, 0);
197  if (ret <= 0) {
198  av_frame_free(&frame);
199  return (ret == 0) ? AVERROR_EOF : ret;
200  }
201 
202  frame->pts = s->next_pts;
203  return ff_filter_frame(outlink, frame);
204  }
205  return ret;
206 }
207 
208 static int filter_frame(AVFilterLink *inlink, AVFrame *in)
209 {
210  AVFilterContext *ctx = inlink->dst;
211  ResampleContext *s = ctx->priv;
212  AVFilterLink *outlink = ctx->outputs[0];
213  int ret;
214 
215  if (s->avr) {
216  AVFrame *out;
217  int delay, nb_samples;
218 
219  /* maximum possible samples lavr can output */
220  delay = avresample_get_delay(s->avr);
221  nb_samples = av_rescale_rnd(in->nb_samples + delay,
222  outlink->sample_rate, inlink->sample_rate,
223  AV_ROUND_UP);
224 
225  out = ff_get_audio_buffer(outlink, nb_samples);
226  if (!out) {
227  ret = AVERROR(ENOMEM);
228  goto fail;
229  }
230 
231  ret = avresample_convert(s->avr, out->extended_data, out->linesize[0],
232  nb_samples, in->extended_data, in->linesize[0],
233  in->nb_samples);
234  if (ret <= 0) {
235  av_frame_free(&out);
236  if (ret < 0)
237  goto fail;
238  }
239 
241 
242  if (s->next_pts == AV_NOPTS_VALUE) {
243  if (in->pts == AV_NOPTS_VALUE) {
244  av_log(ctx, AV_LOG_WARNING, "First timestamp is missing, "
245  "assuming 0.\n");
246  s->next_pts = 0;
247  } else
248  s->next_pts = av_rescale_q(in->pts, inlink->time_base,
249  outlink->time_base);
250  }
251 
252  if (ret > 0) {
253  out->nb_samples = ret;
254  if (in->pts != AV_NOPTS_VALUE) {
255  out->pts = av_rescale_q(in->pts, inlink->time_base,
256  outlink->time_base) -
257  av_rescale(delay, outlink->sample_rate,
258  inlink->sample_rate);
259  } else
260  out->pts = s->next_pts;
261 
262  s->next_pts = out->pts + out->nb_samples;
263 
264  ret = ff_filter_frame(outlink, out);
265  s->got_output = 1;
266  }
267 
268 fail:
269  av_frame_free(&in);
270  } else {
271  in->format = outlink->format;
272  ret = ff_filter_frame(outlink, in);
273  s->got_output = 1;
274  }
275 
276  return ret;
277 }
278 
279 static const AVClass *resample_child_class_next(const AVClass *prev)
280 {
281  return prev ? NULL : avresample_get_class();
282 }
283 
284 static void *resample_child_next(void *obj, void *prev)
285 {
286  ResampleContext *s = obj;
287  return prev ? NULL : s->avr;
288 }
289 
290 static const AVClass resample_class = {
291  .class_name = "resample",
292  .item_name = av_default_item_name,
293  .version = LIBAVUTIL_VERSION_INT,
294  .child_class_next = resample_child_class_next,
296 };
297 
299  {
300  .name = "default",
301  .type = AVMEDIA_TYPE_AUDIO,
302  .filter_frame = filter_frame,
303  },
304  { NULL }
305 };
306 
308  {
309  .name = "default",
310  .type = AVMEDIA_TYPE_AUDIO,
311  .config_props = config_output,
312  .request_frame = request_frame
313  },
314  { NULL }
315 };
316 
318  .name = "resample",
319  .description = NULL_IF_CONFIG_SMALL("Audio resampling and conversion."),
320  .priv_size = sizeof(ResampleContext),
321  .priv_class = &resample_class,
322  .init_dict = init,
323  .uninit = uninit,
325  .inputs = avfilter_af_resample_inputs,
326  .outputs = avfilter_af_resample_outputs,
327 };
void *(* child_next)(void *obj, void *prev)
Return next AVOptions-enabled child or NULL.
Definition: log.h:96
const char * s
Definition: avisynth_c.h:668
static const AVFilterPad avfilter_af_resample_outputs[]
Definition: af_resample.c:307
char * key
Definition: dict.h:81
This structure describes decoded (raw) audio or video data.
Definition: frame.h:96
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:47
const char * name
Filter name.
Definition: avfilter.h:468
int64_t av_rescale_rnd(int64_t a, int64_t b, int64_t c, enum AVRounding) av_const
Rescale a 64-bit integer with specified rounding.
Definition: mathematics.c:60
void * priv
private data for use by the filter
Definition: avfilter.h:648
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: avcodec.h:4153
static const AVFilterPad outputs[]
Definition: af_ashowinfo.c:111
#define LIBAVUTIL_VERSION_INT
Definition: avcodec.h:820
AVDictionaryEntry * av_dict_get(AVDictionary *m, const char *key, const AVDictionaryEntry *prev, int flags)
Get a dictionary entry with matching key.
Definition: dict.c:39
uint8_t ** extended_data
pointers to the data planes/channels.
Definition: frame.h:140
void av_log(void *avcl, int level, const char *fmt,...) av_printf_format(3
Send the specified message to the log if the level is less than or equal to the current av_log_level...
#define av_cold
Definition: avcodec.h:653
enum AVSampleFormat av_get_planar_sample_fmt(enum AVSampleFormat sample_fmt)
Get the planar alternative form of the given sample format.
Definition: samplefmt.c:82
void avresample_free(AVAudioResampleContext **avr)
Free AVAudioResampleContext and associated AVOption values.
Definition: utils.c:273
AVFilter avfilter_af_resample
Definition: af_resample.c:317
const char * name
Pad name.
Definition: internal.h:66
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1118
const char * av_default_item_name(void *ctx)
Return the context name.
Definition: log.c:145
Round toward +infinity.
Definition: mathematics.h:71
AVAudioResampleContext * avr
Definition: af_resample.c:40
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:55
int64_t pts
Presentation timestamp in time_base units (time when frame should be shown to user).
Definition: frame.h:182
void ff_channel_layouts_ref(AVFilterChannelLayouts *f, AVFilterChannelLayouts **ref)
Add *ref as a new reference to f.
Definition: formats.c:413
#define AV_LOG_VERBOSE
Detailed information.
Definition: avcodec.h:4163
static av_cold void uninit(AVFilterContext *ctx)
Definition: af_resample.c:76
void avresample_close(AVAudioResampleContext *avr)
Close AVAudioResampleContext.
Definition: utils.c:257
AVFilterFormats * ff_all_formats(enum AVMediaType type)
Return a list of all formats supported by FFmpeg for the given media type.
Definition: formats.c:343
static AVFrame * frame
Definition: demuxing.c:51
static int config_output(AVFilterLink *outlink)
Definition: af_resample.c:111
A filter pad used for either input or output.
Definition: internal.h:60
int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq) av_const
Rescale a 64-bit integer by 2 rational numbers.
Definition: mathematics.c:130
const AVClass * avresample_get_class(void)
Get the AVClass for AVAudioResampleContext.
Definition: options.c:108
uint8_t pi<< 24) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_U8, uint8_t,(*(constuint8_t *) pi-0x80)*(1.0f/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_U8, uint8_t,(*(constuint8_t *) pi-0x80)*(1.0/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S16, int16_t,(*(constint16_t *) pi >>8)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S16, int16_t,*(constint16_t *) pi *(1.0f/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S16, int16_t,*(constint16_t *) pi *(1.0/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S32, int32_t,(*(constint32_t *) pi >>24)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S32, int32_t,*(constint32_t *) pi *(1.0f/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S32, int32_t,*(constint32_t *) pi *(1.0/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_FLT, float, av_clip_uint8(lrintf(*(constfloat *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_FLT, float, av_clip_int16(lrintf(*(constfloat *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_FLT, float, av_clipl_int32(llrintf(*(constfloat *) pi *(1U<< 31)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_DBL, double, av_clip_uint8(lrint(*(constdouble *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_DBL, double, av_clip_int16(lrint(*(constdouble *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_DBL, double, av_clipl_int32(llrint(*(constdouble *) pi *(1U<< 31))))#defineSET_CONV_FUNC_GROUP(ofmt, ifmt) staticvoidset_generic_function(AudioConvert *ac){}voidff_audio_convert_free(AudioConvert **ac){return;ff_dither_free(&(*ac) ->dc);av_freep(ac);}AudioConvert *ff_audio_convert_alloc(AVAudioResampleContext *avr, enumAVSampleFormatout_fmt, enumAVSampleFormatin_fmt, intchannels, intsample_rate, intapply_map){AudioConvert *ac;intin_planar, out_planar;ac=av_mallocz(sizeof(*ac));returnNULL;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);returnNULL;}returnac;}in_planar=av_sample_fmt_is_planar(in_fmt);out_planar=av_sample_fmt_is_planar(out_fmt);if(in_planar==out_planar){ac->func_type=CONV_FUNC_TYPE_FLAT;ac->planes=in_planar?ac->channels:1;}elseif(in_planar) ac->func_type=CONV_FUNC_TYPE_INTERLEAVE;elseac->func_type=CONV_FUNC_TYPE_DEINTERLEAVE;set_generic_function(ac);ff_audio_convert_init_arm(ac);ff_audio_convert_init_x86(ac);returnac;}intff_audio_convert(AudioConvert *ac, AudioData *out, AudioData *in){intuse_generic=1;intlen=in->nb_samples;intp;if(ac->dc){av_dlog(ac->avr,"%dsamples-audio_convert:%sto%s(dithered)\n", len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt));returnff_convert_dither(ac-> in
static av_cold int init(AVFilterContext *ctx, AVDictionary **opts)
Definition: af_resample.c:49
AVFrame * ff_get_audio_buffer(AVFilterLink *link, int nb_samples)
Request an audio samples buffer with a specific set of permissions.
Definition: audio.c:70
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:151
void av_dict_free(AVDictionary **m)
Free all the memory allocated for an AVDictionary struct and all keys and values. ...
Definition: dict.c:162
AVAudioResampleContext * avresample_alloc_context(void)
Allocate AVAudioResampleContext and set options.
Definition: options.c:94
int av_get_channel_layout_nb_channels(uint64_t channel_layout)
Return the number of channels in the channel layout.
int av_opt_set_int(void *obj, const char *name, int64_t val, int search_flags)
Definition: opt.c:426
AVDictionary * options
Definition: af_resample.c:41
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:123
goto fail
Definition: avfilter.c:963
static const AVClass resample_class
Definition: af_resample.c:290
int64_t av_rescale(int64_t a, int64_t b, int64_t c) av_const
Rescale a 64-bit integer with rounding to nearest.
Definition: mathematics.c:118
static void * resample_child_next(void *obj, void *prev)
Definition: af_resample.c:284
#define AV_OPT_SEARCH_CHILDREN
Search in possible children of the given object first.
Definition: opt.h:540
ret
Definition: avfilter.c:961
static av_cold int init_dict(AVFilterContext *ctx, AVDictionary **opts)
Definition: af_aresample.c:46
char * value
Definition: dict.h:82
AVFilterChannelLayouts * ff_all_channel_layouts(void)
Construct an empty AVFilterChannelLayouts/AVFilterFormats struct – representing any channel layout (w...
Definition: formats.c:388
A list of supported channel layouts.
Definition: formats.h:85
Main libavfilter public API header.
AVFilterLink ** outputs
array of pointers to output links
Definition: avfilter.h:642
int format
format of the frame, -1 if unknown or unset Values correspond to enum AVPixelFormat for video frames...
Definition: frame.h:157
int avresample_get_delay(AVAudioResampleContext *avr)
Return the number of samples currently in the resampling delay buffer.
Definition: resample.c:463
int avresample_available(AVAudioResampleContext *avr)
Return the number of available samples in the output FIFO.
Definition: utils.c:609
sample_rate
void ff_formats_ref(AVFilterFormats *f, AVFilterFormats **ref)
Add *ref as a new reference to formats.
Definition: formats.c:418
int av_opt_set_dict(void *obj, struct AVDictionary **options)
Set all the options from a given dictionary on an object.
Definition: opt.c:1326
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:1347
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:62
Describe the class of an AVClass context structure.
Definition: log.h:50
Filter definition.
Definition: avfilter.h:464
static const AVFilterPad inputs[]
Definition: af_ashowinfo.c:102
AVFilterLink ** inputs
array of pointers to input links
Definition: avfilter.h:635
rational number numerator/denominator
Definition: rational.h:43
int avresample_convert(AVAudioResampleContext *avr, uint8_t **output, int out_plane_size, int out_samples, uint8_t **input, int in_plane_size, int in_samples)
Convert input samples and write them to the output FIFO.
Definition: utils.c:325
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:124
static int filter_frame(AVFilterLink *inlink, AVFrame *in)
Definition: af_resample.c:208
AVFilterFormats * ff_all_samplerates(void)
Definition: formats.c:382
static int request_frame(AVFilterLink *outlink)
Definition: af_resample.c:169
#define AVERROR_EOF
static int query_formats(AVFilterContext *ctx)
Definition: af_resample.c:87
#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 poin...
Definition: opt.h:549
uint8_t pi<< 24) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_U8, uint8_t,(*(constuint8_t *) pi-0x80)*(1.0f/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_U8, uint8_t,(*(constuint8_t *) pi-0x80)*(1.0/(1<< 7))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S16, int16_t,(*(constint16_t *) pi >>8)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S16, int16_t,*(constint16_t *) pi *(1.0f/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S16, int16_t,*(constint16_t *) pi *(1.0/(1<< 15))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_S32, int32_t,(*(constint32_t *) pi >>24)+0x80) CONV_FUNC_GROUP(AV_SAMPLE_FMT_FLT, float, AV_SAMPLE_FMT_S32, int32_t,*(constint32_t *) pi *(1.0f/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_DBL, double, AV_SAMPLE_FMT_S32, int32_t,*(constint32_t *) pi *(1.0/(1U<< 31))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_FLT, float, av_clip_uint8(lrintf(*(constfloat *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_FLT, float, av_clip_int16(lrintf(*(constfloat *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_FLT, float, av_clipl_int32(llrintf(*(constfloat *) pi *(1U<< 31)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_U8, uint8_t, AV_SAMPLE_FMT_DBL, double, av_clip_uint8(lrint(*(constdouble *) pi *(1<< 7))+0x80)) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S16, int16_t, AV_SAMPLE_FMT_DBL, double, av_clip_int16(lrint(*(constdouble *) pi *(1<< 15)))) CONV_FUNC_GROUP(AV_SAMPLE_FMT_S32, int32_t, AV_SAMPLE_FMT_DBL, double, av_clipl_int32(llrint(*(constdouble *) pi *(1U<< 31))))#defineSET_CONV_FUNC_GROUP(ofmt, ifmt) staticvoidset_generic_function(AudioConvert *ac){}voidff_audio_convert_free(AudioConvert **ac){return;ff_dither_free(&(*ac) ->dc);av_freep(ac);}AudioConvert *ff_audio_convert_alloc(AVAudioResampleContext *avr, enumAVSampleFormatout_fmt, enumAVSampleFormatin_fmt, intchannels, intsample_rate, intapply_map){AudioConvert *ac;intin_planar, out_planar;ac=av_mallocz(sizeof(*ac));returnNULL;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);returnNULL;}returnac;}in_planar=av_sample_fmt_is_planar(in_fmt);out_planar=av_sample_fmt_is_planar(out_fmt);if(in_planar==out_planar){ac->func_type=CONV_FUNC_TYPE_FLAT;ac->planes=in_planar?ac->channels:1;}elseif(in_planar) ac->func_type=CONV_FUNC_TYPE_INTERLEAVE;elseac->func_type=CONV_FUNC_TYPE_DEINTERLEAVE;set_generic_function(ac);ff_audio_convert_init_arm(ac);ff_audio_convert_init_x86(ac);returnac;}intff_audio_convert(AudioConvert *ac, AudioData *out, AudioData *in){intuse_generic=1;intlen=in->nb_samples;intp;if(ac->dc){av_dlog(ac->avr,"%dsamples-audio_convert:%sto%s(dithered)\n", len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt));returnff_convert_dither(ac-> out
A list of supported formats for one end of a filter link.
Definition: formats.h:64
#define AVERROR(e)
An instance of a filter.
Definition: avfilter.h:627
#define AV_DICT_IGNORE_SUFFIX
Definition: dict.h:68
static const AVClass * resample_child_class_next(const AVClass *prev)
Definition: af_resample.c:279
static const AVFilterPad avfilter_af_resample_inputs[]
Definition: af_resample.c:298
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
int ff_request_frame(AVFilterLink *link)
Request an input frame from the filter at the other end of the link.
Definition: avfilter.c:335
internal API functions
int avresample_open(AVAudioResampleContext *avr)
Initialize AVAudioResampleContext.
Definition: utils.c:35
int nb_samples
number of audio samples (per channel) described by this frame
Definition: frame.h:150
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avcodec.h:2278
int64_t next_pts
Definition: af_resample.c:43
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.