FFmpeg
af_aresample.c
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1 /*
2  * Copyright (c) 2011 Stefano Sabatini
3  * Copyright (c) 2011 Mina Nagy Zaki
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  * resampling audio filter
25  */
26 
27 #include "libavutil/avstring.h"
29 #include "libavutil/opt.h"
30 #include "libavutil/samplefmt.h"
31 #include "libavutil/avassert.h"
33 #include "avfilter.h"
34 #include "audio.h"
35 #include "filters.h"
36 #include "formats.h"
37 
38 typedef struct AResampleContext {
39  const AVClass *class;
41  double ratio;
42  struct SwrContext *swr;
44  int more_data;
45  int eof;
47 
49 {
50  AResampleContext *aresample = ctx->priv;
51 
52  aresample->next_pts = AV_NOPTS_VALUE;
53  aresample->swr = swr_alloc();
54  if (!aresample->swr)
55  return AVERROR(ENOMEM);
56 
57  return 0;
58 }
59 
61 {
62  AResampleContext *aresample = ctx->priv;
63  swr_free(&aresample->swr);
64 }
65 
66 static int query_formats(const AVFilterContext *ctx,
67  AVFilterFormatsConfig **cfg_in,
68  AVFilterFormatsConfig **cfg_out)
69 {
70  const AResampleContext *aresample = ctx->priv;
71  enum AVSampleFormat out_format;
72  AVChannelLayout out_layout = { 0 };
73  int64_t out_rate;
74 
75  AVFilterFormats *in_formats, *out_formats;
76  AVFilterFormats *in_samplerates, *out_samplerates;
77  AVFilterChannelLayouts *in_layouts, *out_layouts;
78  int ret;
79 
80  if (aresample->sample_rate_arg > 0)
81  av_opt_set_int(aresample->swr, "osr", aresample->sample_rate_arg, 0);
82  av_opt_get_sample_fmt(aresample->swr, "osf", 0, &out_format);
83  av_opt_get_int(aresample->swr, "osr", 0, &out_rate);
84 
85  in_formats = ff_all_formats(AVMEDIA_TYPE_AUDIO);
86  if ((ret = ff_formats_ref(in_formats, &cfg_in[0]->formats)) < 0)
87  return ret;
88 
89  in_samplerates = ff_all_samplerates();
90  if ((ret = ff_formats_ref(in_samplerates, &cfg_in[0]->samplerates)) < 0)
91  return ret;
92 
93  in_layouts = ff_all_channel_counts();
94  if ((ret = ff_channel_layouts_ref(in_layouts, &cfg_in[0]->channel_layouts)) < 0)
95  return ret;
96 
97  if(out_rate > 0) {
98  int ratelist[] = { out_rate, -1 };
99  out_samplerates = ff_make_format_list(ratelist);
100  } else {
101  out_samplerates = ff_all_samplerates();
102  }
103 
104  if ((ret = ff_formats_ref(out_samplerates, &cfg_out[0]->samplerates)) < 0)
105  return ret;
106 
107  if(out_format != AV_SAMPLE_FMT_NONE) {
108  int formatlist[] = { out_format, -1 };
109  out_formats = ff_make_format_list(formatlist);
110  } else
111  out_formats = ff_all_formats(AVMEDIA_TYPE_AUDIO);
112  if ((ret = ff_formats_ref(out_formats, &cfg_out[0]->formats)) < 0)
113  return ret;
114 
115  av_opt_get_chlayout(aresample->swr, "ochl", 0, &out_layout);
116  if (av_channel_layout_check(&out_layout)) {
117  const AVChannelLayout layout_list[] = { out_layout, { 0 } };
118  out_layouts = ff_make_channel_layout_list(layout_list);
119  } else
120  out_layouts = ff_all_channel_counts();
121  av_channel_layout_uninit(&out_layout);
122 
123  return ff_channel_layouts_ref(out_layouts, &cfg_out[0]->channel_layouts);
124 }
125 
126 
127 static int config_output(AVFilterLink *outlink)
128 {
129  int ret;
130  AVFilterContext *ctx = outlink->src;
131  AVFilterLink *inlink = ctx->inputs[0];
132  AResampleContext *aresample = ctx->priv;
133  AVChannelLayout out_layout = { 0 };
134  int64_t out_rate;
135  enum AVSampleFormat out_format;
136  char inchl_buf[128], outchl_buf[128];
137 
138  ret = swr_alloc_set_opts2(&aresample->swr,
139  &outlink->ch_layout, outlink->format, outlink->sample_rate,
140  &inlink->ch_layout, inlink->format, inlink->sample_rate,
141  0, ctx);
142  if (ret < 0)
143  return ret;
144 
145  ret = swr_init(aresample->swr);
146  if (ret < 0)
147  return ret;
148 
149  av_opt_get_int(aresample->swr, "osr", 0, &out_rate);
150  av_opt_get_chlayout(aresample->swr, "ochl", 0, &out_layout);
151  av_opt_get_sample_fmt(aresample->swr, "osf", 0, &out_format);
152  outlink->time_base = (AVRational) {1, out_rate};
153 
154  av_assert0(outlink->sample_rate == out_rate);
155  av_assert0(!av_channel_layout_compare(&outlink->ch_layout, &out_layout));
156  av_assert0(outlink->format == out_format);
157 
158  av_channel_layout_uninit(&out_layout);
159 
160  aresample->ratio = (double)outlink->sample_rate / inlink->sample_rate;
161 
162  av_channel_layout_describe(&inlink ->ch_layout, inchl_buf, sizeof(inchl_buf));
163  av_channel_layout_describe(&outlink->ch_layout, outchl_buf, sizeof(outchl_buf));
164 
165  av_log(ctx, AV_LOG_VERBOSE, "ch:%d chl:%s fmt:%s r:%dHz -> ch:%d chl:%s fmt:%s r:%dHz\n",
166  inlink ->ch_layout.nb_channels, inchl_buf, av_get_sample_fmt_name(inlink->format), inlink->sample_rate,
167  outlink->ch_layout.nb_channels, outchl_buf, av_get_sample_fmt_name(outlink->format), outlink->sample_rate);
168  return 0;
169 }
170 
171 static int filter_frame(AVFilterLink *inlink, AVFrame *insamplesref)
172 {
173  AVFilterContext *ctx = inlink->dst;
174  AResampleContext *aresample = ctx->priv;
175  const int n_in = insamplesref->nb_samples;
176  int64_t delay;
177  int n_out = n_in * aresample->ratio + 32;
178  AVFilterLink *const outlink = inlink->dst->outputs[0];
179  AVFrame *outsamplesref;
180  int ret;
181 
182  delay = swr_get_delay(aresample->swr, outlink->sample_rate);
183  if (delay > 0)
184  n_out += FFMIN(delay, FFMAX(4096, n_out));
185 
186  outsamplesref = ff_get_audio_buffer(outlink, n_out);
187 
188  if(!outsamplesref) {
189  av_frame_free(&insamplesref);
190  return AVERROR(ENOMEM);
191  }
192 
193  av_frame_copy_props(outsamplesref, insamplesref);
194  outsamplesref->format = outlink->format;
195  ret = av_channel_layout_copy(&outsamplesref->ch_layout, &outlink->ch_layout);
196  if (ret < 0) {
197  av_frame_free(&outsamplesref);
198  av_frame_free(&insamplesref);
199  return ret;
200  }
201  outsamplesref->sample_rate = outlink->sample_rate;
202 
203  if(insamplesref->pts != AV_NOPTS_VALUE) {
204  int64_t inpts = av_rescale(insamplesref->pts, inlink->time_base.num * (int64_t)outlink->sample_rate * inlink->sample_rate, inlink->time_base.den);
205  int64_t outpts= swr_next_pts(aresample->swr, inpts);
206  aresample->next_pts =
207  outsamplesref->pts = ROUNDED_DIV(outpts, inlink->sample_rate);
208  } else {
209  outsamplesref->pts = AV_NOPTS_VALUE;
210  }
211  n_out = swr_convert(aresample->swr, outsamplesref->extended_data, n_out,
212  (void *)insamplesref->extended_data, n_in);
213  if (n_out <= 0) {
214  av_frame_free(&outsamplesref);
215  av_frame_free(&insamplesref);
217  return 0;
218  }
219 
220  aresample->more_data = outsamplesref->nb_samples == n_out; // Indicate that there is probably more data in our buffers
221 
222  outsamplesref->nb_samples = n_out;
223 
224  ret = ff_filter_frame(outlink, outsamplesref);
225  av_frame_free(&insamplesref);
226  return ret;
227 }
228 
229 static int flush_frame(AVFilterLink *outlink, int final, AVFrame **outsamplesref_ret)
230 {
231  AVFilterContext *ctx = outlink->src;
232  AResampleContext *aresample = ctx->priv;
233  AVFilterLink *const inlink = outlink->src->inputs[0];
234  AVFrame *outsamplesref;
235  int n_out = 4096;
236  int64_t pts;
237 
238  outsamplesref = ff_get_audio_buffer(outlink, n_out);
239  *outsamplesref_ret = outsamplesref;
240  if (!outsamplesref)
241  return AVERROR(ENOMEM);
242 
243  pts = swr_next_pts(aresample->swr, INT64_MIN);
244  pts = ROUNDED_DIV(pts, inlink->sample_rate);
245 
246  n_out = swr_convert(aresample->swr, outsamplesref->extended_data, n_out, final ? NULL : (void*)outsamplesref->extended_data, 0);
247  if (n_out <= 0) {
248  av_frame_free(&outsamplesref);
249  return (n_out == 0) ? AVERROR_EOF : n_out;
250  }
251 
252  outsamplesref->sample_rate = outlink->sample_rate;
253  outsamplesref->nb_samples = n_out;
254 
255  outsamplesref->pts = pts;
256 
257  return 0;
258 }
259 
260 static int request_frame(AVFilterLink *outlink)
261 {
262  AVFilterContext *ctx = outlink->src;
263  AVFilterLink *inlink = ctx->inputs[0];
264  AResampleContext *aresample = ctx->priv;
265  int ret = 0, status;
266  int64_t pts;
267 
268  // First try to get data from the internal buffers
269  if (aresample->more_data) {
270  AVFrame *outsamplesref;
271 
272  if (flush_frame(outlink, 0, &outsamplesref) >= 0) {
273  return ff_filter_frame(outlink, outsamplesref);
274  }
275  }
276  aresample->more_data = 0;
277 
278  if (!aresample->eof && ff_inlink_acknowledge_status(inlink, &status, &pts))
279  aresample->eof = 1;
280 
281  // Second request more data from the input
282  if (!aresample->eof)
284 
285  // Third if we hit the end flush
286  if (aresample->eof) {
287  AVFrame *outsamplesref;
288 
289  if ((ret = flush_frame(outlink, 1, &outsamplesref)) < 0) {
290  if (ret == AVERROR_EOF) {
291  ff_outlink_set_status(outlink, AVERROR_EOF, aresample->next_pts);
292  return 0;
293  }
294  return ret;
295  }
296 
297  return ff_filter_frame(outlink, outsamplesref);
298  }
299 
300  ff_filter_set_ready(ctx, 100);
301  return 0;
302 }
303 
305 {
306  AResampleContext *aresample = ctx->priv;
307  AVFilterLink *inlink = ctx->inputs[0];
308  AVFilterLink *outlink = ctx->outputs[0];
309 
311 
312  if (!aresample->eof && ff_inlink_queued_frames(inlink)) {
313  AVFrame *frame = NULL;
314  int ret;
315 
317  if (ret < 0)
318  return ret;
319  if (ret > 0)
320  return filter_frame(inlink, frame);
321  }
322 
323  return request_frame(outlink);
324 }
325 
326 static const AVClass *resample_child_class_iterate(void **iter)
327 {
328  const AVClass *c = *iter ? NULL : swr_get_class();
329  *iter = (void*)(uintptr_t)c;
330  return c;
331 }
332 
333 static void *resample_child_next(void *obj, void *prev)
334 {
335  AResampleContext *s = obj;
336  return prev ? NULL : s->swr;
337 }
338 
339 #define OFFSET(x) offsetof(AResampleContext, x)
340 #define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
341 
342 static const AVOption options[] = {
343  {"sample_rate", NULL, OFFSET(sample_rate_arg), AV_OPT_TYPE_INT, {.i64=0}, 0, INT_MAX, FLAGS },
344  {NULL}
345 };
346 
347 static const AVClass aresample_class = {
348  .class_name = "aresample",
349  .item_name = av_default_item_name,
350  .option = options,
351  .version = LIBAVUTIL_VERSION_INT,
352  .child_class_iterate = resample_child_class_iterate,
354 };
355 
356 static const AVFilterPad aresample_outputs[] = {
357  {
358  .name = "default",
359  .config_props = config_output,
360  .type = AVMEDIA_TYPE_AUDIO,
361  },
362 };
363 
365  .name = "aresample",
366  .description = NULL_IF_CONFIG_SMALL("Resample audio data."),
367  .preinit = preinit,
368  .activate = activate,
369  .uninit = uninit,
370  .priv_size = sizeof(AResampleContext),
371  .priv_class = &aresample_class,
375 };
formats
formats
Definition: signature.h:47
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:98
AVFilterChannelLayouts
A list of supported channel layouts.
Definition: formats.h:85
SwrContext::outpts
int64_t outpts
output PTS
Definition: swresample_internal.h:158
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
ff_make_format_list
AVFilterFormats * ff_make_format_list(const int *fmts)
Create a list of supported formats.
Definition: formats.c:435
ff_filter_frame
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1061
ff_channel_layouts_ref
int ff_channel_layouts_ref(AVFilterChannelLayouts *f, AVFilterChannelLayouts **ref)
Add *ref as a new reference to f.
Definition: formats.c:673
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
int64_t
long long int64_t
Definition: coverity.c:34
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
FLAGS
#define FLAGS
Definition: af_aresample.c:340
av_frame_free
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:162
ff_all_channel_counts
AVFilterChannelLayouts * ff_all_channel_counts(void)
Construct an AVFilterChannelLayouts coding for any channel layout, with known or unknown disposition.
Definition: formats.c:621
FILTER_INPUTS
#define FILTER_INPUTS(array)
Definition: filters.h:262
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:389
AVFrame::pts
int64_t pts
Presentation timestamp in time_base units (time when frame should be shown to user).
Definition: frame.h:501
AVOption
AVOption.
Definition: opt.h:429
config_output
static int config_output(AVFilterLink *outlink)
Definition: af_aresample.c:127
AV_LOG_VERBOSE
#define AV_LOG_VERBOSE
Detailed information.
Definition: log.h:225
preinit
static av_cold int preinit(AVFilterContext *ctx)
Definition: af_aresample.c:48
FFMAX
#define FFMAX(a, b)
Definition: macros.h:47
AVFilter::name
const char * name
Filter name.
Definition: avfilter.h:205
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:327
FF_FILTER_FORWARD_STATUS_BACK
#define FF_FILTER_FORWARD_STATUS_BACK(outlink, inlink)
Forward the status on an output link to an input link.
Definition: filters.h:434
AVFilterFormats
A list of supported formats for one end of a filter link.
Definition: formats.h:64
formats.h
ff_inlink_consume_frame
int ff_inlink_consume_frame(AVFilterLink *link, AVFrame **rframe)
Take a frame from the link's FIFO and update the link's stats.
Definition: avfilter.c:1490
activate
static int activate(AVFilterContext *ctx)
Definition: af_aresample.c:304
samplefmt.h
AVFrame::ch_layout
AVChannelLayout ch_layout
Channel layout of the audio data.
Definition: frame.h:790
pts
static int64_t pts
Definition: transcode_aac.c:644
ff_all_formats
AVFilterFormats * ff_all_formats(enum AVMediaType type)
Return a list of all formats supported by FFmpeg for the given media type.
Definition: formats.c:535
swr_next_pts
int64_t swr_next_pts(struct SwrContext *s, int64_t pts)
Convert the next timestamp from input to output timestamps are in 1/(in_sample_rate * out_sample_rate...
Definition: swresample.c:924
AVFilterPad
A filter pad used for either input or output.
Definition: filters.h:38
swr_convert
int attribute_align_arg swr_convert(struct SwrContext *s, uint8_t *const *out_arg, int out_count, const uint8_t *const *in_arg, int in_count)
Convert audio.
Definition: swresample.c:719
swr_get_delay
int64_t swr_get_delay(struct SwrContext *s, int64_t base)
Gets the delay the next input sample will experience relative to the next output sample.
Definition: swresample.c:874
options
static const AVOption options[]
Definition: af_aresample.c:342
avassert.h
resample_child_next
static void * resample_child_next(void *obj, void *prev)
Definition: af_aresample.c:333
av_cold
#define av_cold
Definition: attributes.h:90
swr_init
av_cold int swr_init(struct SwrContext *s)
Initialize context after user parameters have been set.
Definition: swresample.c:140
av_channel_layout_describe
int av_channel_layout_describe(const AVChannelLayout *channel_layout, char *buf, size_t buf_size)
Get a human-readable string describing the channel layout properties.
Definition: channel_layout.c:651
ff_outlink_set_status
static void ff_outlink_set_status(AVFilterLink *link, int status, int64_t pts)
Set the status field of a link from the source filter.
Definition: filters.h:424
ff_inlink_request_frame
void ff_inlink_request_frame(AVFilterLink *link)
Mark that a frame is wanted on the link.
Definition: avfilter.c:1593
s
#define s(width, name)
Definition: cbs_vp9.c:198
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
ff_formats_ref
int ff_formats_ref(AVFilterFormats *f, AVFilterFormats **ref)
Add *ref as a new reference to formats.
Definition: formats.c:678
swr_alloc
av_cold struct SwrContext * swr_alloc(void)
Allocate SwrContext.
Definition: options.c:148
av_assert0
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:40
filters.h
resample_child_class_iterate
static const AVClass * resample_child_class_iterate(void **iter)
Definition: af_aresample.c:326
ctx
AVFormatContext * ctx
Definition: movenc.c:49
av_get_sample_fmt_name
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:51
SwrContext
The libswresample context.
Definition: swresample_internal.h:95
FILTER_OUTPUTS
#define FILTER_OUTPUTS(array)
Definition: filters.h:263
LIBAVUTIL_VERSION_INT
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:75
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:725
AResampleContext::sample_rate_arg
int sample_rate_arg
Definition: af_aresample.c:40
swr_get_class
const AVClass * swr_get_class(void)
Get the AVClass for SwrContext.
Definition: options.c:143
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
AVFilterContext::inputs
AVFilterLink ** inputs
array of pointers to input links
Definition: avfilter.h:465
ROUNDED_DIV
#define ROUNDED_DIV(a, b)
Definition: common.h:58
av_default_item_name
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:237
options
Definition: swscale.c:42
av_opt_get_sample_fmt
int av_opt_get_sample_fmt(void *obj, const char *name, int search_flags, enum AVSampleFormat *out_fmt)
Definition: opt.c:1362
ff_audio_default_filterpad
const AVFilterPad ff_audio_default_filterpad[1]
An AVFilterPad array whose only entry has name "default" and is of type AVMEDIA_TYPE_AUDIO.
Definition: audio.c:34
double
double
Definition: af_crystalizer.c:132
av_opt_get_int
int av_opt_get_int(void *obj, const char *name, int search_flags, int64_t *out_val)
Definition: opt.c:1273
ff_inlink_acknowledge_status
int ff_inlink_acknowledge_status(AVFilterLink *link, int *rstatus, int64_t *rpts)
Test and acknowledge the change of status on the link.
Definition: avfilter.c:1437
swresample.h
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
AVFilterFormatsConfig
Lists of formats / etc.
Definition: avfilter.h:111
av_opt_set_int
int av_opt_set_int(void *obj, const char *name, int64_t val, int search_flags)
Definition: opt.c:880
ff_inlink_queued_frames
size_t ff_inlink_queued_frames(AVFilterLink *link)
Get the number of frames available on the link.
Definition: avfilter.c:1453
query_formats
static int query_formats(const AVFilterContext *ctx, AVFilterFormatsConfig **cfg_in, AVFilterFormatsConfig **cfg_out)
Definition: af_aresample.c:66
uninit
static av_cold void uninit(AVFilterContext *ctx)
Definition: af_aresample.c:60
swr_alloc_set_opts2
int swr_alloc_set_opts2(struct SwrContext **ps, const AVChannelLayout *out_ch_layout, enum AVSampleFormat out_sample_fmt, int out_sample_rate, const AVChannelLayout *in_ch_layout, enum AVSampleFormat in_sample_fmt, int in_sample_rate, int log_offset, void *log_ctx)
Allocate SwrContext if needed and set/reset common parameters.
Definition: swresample.c:40
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:94
AVChannelLayout
An AVChannelLayout holds information about the channel layout of audio data.
Definition: channel_layout.h:317
AVClass::child_next
void *(* child_next)(void *obj, void *prev)
Return next AVOptions-enabled child or NULL.
Definition: log.h:149
AVFrame::sample_rate
int sample_rate
Sample rate of the audio data.
Definition: frame.h:588
AV_SAMPLE_FMT_NONE
@ AV_SAMPLE_FMT_NONE
Definition: samplefmt.h:56
AResampleContext::ratio
double ratio
Definition: af_aresample.c:41
AV_NOPTS_VALUE
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248
AResampleContext::eof
int eof
Definition: af_aresample.c:45
aresample_outputs
static const AVFilterPad aresample_outputs[]
Definition: af_aresample.c:356
swr_free
av_cold void swr_free(SwrContext **ss)
Free the given SwrContext and set the pointer to NULL.
Definition: swresample.c:121
AVFrame::format
int format
format of the frame, -1 if unknown or unset Values correspond to enum AVPixelFormat for video frames,...
Definition: frame.h:476
FF_FILTER_FORWARD_WANTED
FF_FILTER_FORWARD_WANTED(outlink, inlink)
AResampleContext
Definition: af_aresample.c:38
av_channel_layout_compare
int av_channel_layout_compare(const AVChannelLayout *chl, const AVChannelLayout *chl1)
Check whether two channel layouts are semantically the same, i.e.
Definition: channel_layout.c:807
AResampleContext::swr
struct SwrContext * swr
Definition: af_aresample.c:42
flush_frame
static int flush_frame(AVFilterLink *outlink, int final, AVFrame **outsamplesref_ret)
Definition: af_aresample.c:229
aresample_class
static const AVClass aresample_class
Definition: af_aresample.c:347
AVFrame::nb_samples
int nb_samples
number of audio samples (per channel) described by this frame
Definition: frame.h:469
AVFrame::extended_data
uint8_t ** extended_data
pointers to the data planes/channels.
Definition: frame.h:450
OFFSET
#define OFFSET(x)
Definition: af_aresample.c:339
AVSampleFormat
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:55
FILTER_QUERY_FUNC2
#define FILTER_QUERY_FUNC2(func)
Definition: filters.h:239
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
filter_frame
static int filter_frame(AVFilterLink *inlink, AVFrame *insamplesref)
Definition: af_aresample.c:171
AVFilterPad::name
const char * name
Pad name.
Definition: filters.h:44
av_rescale
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
AVFilter
Filter definition.
Definition: avfilter.h:201
AResampleContext::next_pts
int64_t next_pts
Definition: af_aresample.c:43
ret
ret
Definition: filter_design.txt:187
AVClass::class_name
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:80
frame
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
Definition: filter_design.txt:264
av_channel_layout_check
int av_channel_layout_check(const AVChannelLayout *channel_layout)
Check whether a channel layout is valid, i.e.
Definition: channel_layout.c:781
ff_all_samplerates
AVFilterFormats * ff_all_samplerates(void)
Definition: formats.c:606
status
ov_status_e status
Definition: dnn_backend_openvino.c:100
channel_layout.h
AV_OPT_TYPE_INT
@ AV_OPT_TYPE_INT
Underlying C type is int.
Definition: opt.h:259
avfilter.h
av_channel_layout_uninit
void av_channel_layout_uninit(AVChannelLayout *channel_layout)
Free any allocated data in the channel layout and reset the channel count to 0.
Definition: channel_layout.c:440
av_opt_get_chlayout
int av_opt_get_chlayout(void *obj, const char *name, int search_flags, AVChannelLayout *cl)
Definition: opt.c:1367
AVFilterContext
An instance of a filter.
Definition: avfilter.h:457
av_channel_layout_copy
int av_channel_layout_copy(AVChannelLayout *dst, const AVChannelLayout *src)
Make a copy of a channel layout.
Definition: channel_layout.c:447
audio.h
channel_layouts
static const uint16_t channel_layouts[7]
Definition: dca_lbr.c:112
ff_af_aresample
const AVFilter ff_af_aresample
Definition: af_aresample.c:364
ff_make_channel_layout_list
AVFilterChannelLayouts * ff_make_channel_layout_list(const AVChannelLayout *fmts)
Definition: formats.c:444
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
request_frame
static int request_frame(AVFilterLink *outlink)
Definition: af_aresample.c:260
AResampleContext::more_data
int more_data
Definition: af_aresample.c:44
avstring.h
ff_filter_set_ready
void ff_filter_set_ready(AVFilterContext *filter, unsigned priority)
Mark a filter ready and schedule it for activation.
Definition: avfilter.c:239