FFmpeg
f_streamselect.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 #include "libavutil/avstring.h"
20 #include "libavutil/internal.h"
21 #include "libavutil/opt.h"
22 #include "avfilter.h"
23 #include "audio.h"
24 #include "filters.h"
25 #include "formats.h"
26 #include "framesync.h"
27 #include "internal.h"
28 #include "video.h"
29 
30 typedef struct StreamSelectContext {
31  const AVClass *class;
32  int nb_inputs;
33  char *map_str;
34  int *map;
35  int nb_map;
36  int is_audio;
37  int64_t *last_pts;
41 
42 #define OFFSET(x) offsetof(StreamSelectContext, x)
43 #define FLAGS AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_FILTERING_PARAM
44 #define TFLAGS AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_FILTERING_PARAM | AV_OPT_FLAG_RUNTIME_PARAM
45 static const AVOption streamselect_options[] = {
46  { "inputs", "number of input streams", OFFSET(nb_inputs), AV_OPT_TYPE_INT, {.i64=2}, 2, INT_MAX, .flags=FLAGS },
47  { "map", "input indexes to remap to outputs", OFFSET(map_str), AV_OPT_TYPE_STRING, {.str=NULL}, .flags=TFLAGS },
48  { NULL }
49 };
50 
51 AVFILTER_DEFINE_CLASS(streamselect);
52 
54 {
55  AVFilterContext *ctx = fs->parent;
57  AVFrame **in = s->frames;
58  int i, j, ret = 0, have_out = 0;
59 
60  for (i = 0; i < ctx->nb_inputs; i++) {
61  if ((ret = ff_framesync_get_frame(&s->fs, i, &in[i], 0)) < 0)
62  return ret;
63  }
64 
65  for (j = 0; j < ctx->nb_inputs; j++) {
66  for (i = 0; i < s->nb_map; i++) {
67  if (s->map[i] == j) {
68  AVFrame *out;
69 
70  if (s->is_audio && s->last_pts[j] == in[j]->pts &&
71  ctx->outputs[i]->frame_count_in > 0)
72  continue;
73  out = av_frame_clone(in[j]);
74  if (!out)
75  return AVERROR(ENOMEM);
76 
77  out->pts = av_rescale_q(s->fs.pts, s->fs.time_base, ctx->outputs[i]->time_base);
78  s->last_pts[j] = in[j]->pts;
79  ret = ff_filter_frame(ctx->outputs[i], out);
80  have_out = 1;
81  if (ret < 0)
82  return ret;
83  }
84  }
85  }
86 
87  if (!have_out)
88  ff_filter_set_ready(ctx, 100);
89  return ret;
90 }
91 
93 {
94  StreamSelectContext *s = ctx->priv;
95  return ff_framesync_activate(&s->fs);
96 }
97 
98 static int config_output(AVFilterLink *outlink)
99 {
100  AVFilterContext *ctx = outlink->src;
101  StreamSelectContext *s = ctx->priv;
102  const int outlink_idx = FF_OUTLINK_IDX(outlink);
103  const int inlink_idx = s->map[outlink_idx];
104  AVFilterLink *inlink = ctx->inputs[inlink_idx];
105  FFFrameSyncIn *in;
106  int i, ret;
107 
108  av_log(ctx, AV_LOG_VERBOSE, "config output link %d "
109  "with settings from input link %d\n",
110  outlink_idx, inlink_idx);
111 
112  switch (outlink->type) {
113  case AVMEDIA_TYPE_VIDEO:
114  outlink->w = inlink->w;
115  outlink->h = inlink->h;
116  outlink->sample_aspect_ratio = inlink->sample_aspect_ratio;
117  outlink->frame_rate = inlink->frame_rate;
118  break;
119  case AVMEDIA_TYPE_AUDIO:
120  outlink->sample_rate = inlink->sample_rate;
121  outlink->channels = inlink->channels;
122  outlink->channel_layout = inlink->channel_layout;
123  break;
124  }
125 
126  outlink->time_base = inlink->time_base;
127  outlink->format = inlink->format;
128 
129  if (s->fs.opaque == s)
130  return 0;
131 
132  if ((ret = ff_framesync_init(&s->fs, ctx, ctx->nb_inputs)) < 0)
133  return ret;
134 
135  in = s->fs.in;
136  s->fs.opaque = s;
138 
139  for (i = 0; i < ctx->nb_inputs; i++) {
140  in[i].time_base = ctx->inputs[i]->time_base;
141  in[i].sync = 1;
142  in[i].before = EXT_STOP;
143  in[i].after = EXT_STOP;
144  }
145 
146  s->frames = av_calloc(ctx->nb_inputs, sizeof(*s->frames));
147  if (!s->frames)
148  return AVERROR(ENOMEM);
149 
150  return ff_framesync_configure(&s->fs);
151 }
152 
153 static int parse_definition(AVFilterContext *ctx, int nb_pads, int is_input, int is_audio)
154 {
155  const char *padtype = is_input ? "in" : "out";
156  int i = 0, ret = 0;
157 
158  for (i = 0; i < nb_pads; i++) {
159  AVFilterPad pad = { 0 };
160 
161  pad.type = is_audio ? AVMEDIA_TYPE_AUDIO : AVMEDIA_TYPE_VIDEO;
162 
163  pad.name = av_asprintf("%sput%d", padtype, i);
164  if (!pad.name)
165  return AVERROR(ENOMEM);
166 
167  av_log(ctx, AV_LOG_DEBUG, "Add %s pad %s\n", padtype, pad.name);
168 
169  if (is_input) {
170  ret = ff_insert_inpad(ctx, i, &pad);
171  } else {
173  ret = ff_insert_outpad(ctx, i, &pad);
174  }
175 
176  if (ret < 0) {
177  av_freep(&pad.name);
178  return ret;
179  }
180  }
181 
182  return 0;
183 }
184 
185 static int parse_mapping(AVFilterContext *ctx, const char *map)
186 {
187  StreamSelectContext *s = ctx->priv;
188  int *new_map;
189  int new_nb_map = 0;
190 
191  if (!map) {
192  av_log(ctx, AV_LOG_ERROR, "mapping definition is not set\n");
193  return AVERROR(EINVAL);
194  }
195 
196  new_map = av_calloc(s->nb_inputs, sizeof(*new_map));
197  if (!new_map)
198  return AVERROR(ENOMEM);
199 
200  while (1) {
201  char *p;
202  const int n = strtol(map, &p, 0);
203 
204  av_log(ctx, AV_LOG_DEBUG, "n=%d map=%p p=%p\n", n, map, p);
205 
206  if (map == p)
207  break;
208  map = p;
209 
210  if (new_nb_map >= s->nb_inputs) {
211  av_log(ctx, AV_LOG_ERROR, "Unable to map more than the %d "
212  "input pads available\n", s->nb_inputs);
213  av_free(new_map);
214  return AVERROR(EINVAL);
215  }
216 
217  if (n < 0 || n >= ctx->nb_inputs) {
218  av_log(ctx, AV_LOG_ERROR, "Input stream index %d doesn't exist "
219  "(there is only %d input streams defined)\n",
220  n, s->nb_inputs);
221  av_free(new_map);
222  return AVERROR(EINVAL);
223  }
224 
225  av_log(ctx, AV_LOG_VERBOSE, "Map input stream %d to output stream %d\n", n, new_nb_map);
226  new_map[new_nb_map++] = n;
227  }
228 
229  if (!new_nb_map) {
230  av_log(ctx, AV_LOG_ERROR, "invalid mapping\n");
231  av_free(new_map);
232  return AVERROR(EINVAL);
233  }
234 
235  av_freep(&s->map);
236  s->map = new_map;
237  s->nb_map = new_nb_map;
238 
239  av_log(ctx, AV_LOG_VERBOSE, "%d map set\n", s->nb_map);
240 
241  return 0;
242 }
243 
244 static int process_command(AVFilterContext *ctx, const char *cmd, const char *args,
245  char *res, int res_len, int flags)
246 {
247  if (!strcmp(cmd, "map")) {
248  int ret = parse_mapping(ctx, args);
249 
250  if (ret < 0)
251  return ret;
252  return avfilter_config_links(ctx);
253  }
254  return AVERROR(ENOSYS);
255 }
256 
258 {
259  StreamSelectContext *s = ctx->priv;
260  int ret, nb_outputs = 0;
261  char *map = s->map_str;
262 
263  if (!strcmp(ctx->filter->name, "astreamselect"))
264  s->is_audio = 1;
265 
266  for (; map;) {
267  char *p;
268 
269  strtol(map, &p, 0);
270  if (map == p)
271  break;
272  nb_outputs++;
273  map = p;
274  }
275 
276  s->last_pts = av_calloc(s->nb_inputs, sizeof(*s->last_pts));
277  if (!s->last_pts)
278  return AVERROR(ENOMEM);
279 
280  if ((ret = parse_definition(ctx, s->nb_inputs, 1, s->is_audio)) < 0 ||
281  (ret = parse_definition(ctx, nb_outputs, 0, s->is_audio)) < 0)
282  return ret;
283 
284  av_log(ctx, AV_LOG_DEBUG, "Configured with %d inpad and %d outpad\n",
285  ctx->nb_inputs, ctx->nb_outputs);
286 
287  return parse_mapping(ctx, s->map_str);
288 }
289 
291 {
292  StreamSelectContext *s = ctx->priv;
293 
294  av_freep(&s->last_pts);
295  av_freep(&s->map);
296  av_freep(&s->frames);
297  ff_framesync_uninit(&s->fs);
298 
299  for (int i = 0; i < ctx->nb_inputs; i++)
300  av_freep(&ctx->input_pads[i].name);
301 
302  for (int i = 0; i < ctx->nb_outputs; i++)
303  av_freep(&ctx->output_pads[i].name);
304 }
305 
307 {
310  int ret, i;
311 
312  for (i = 0; i < ctx->nb_inputs; i++) {
313  formats = ff_all_formats(ctx->inputs[i]->type);
314  if ((ret = ff_set_common_formats(ctx, formats)) < 0)
315  return ret;
316 
317  if (ctx->inputs[i]->type == AVMEDIA_TYPE_AUDIO) {
318  rates = ff_all_samplerates();
319  if ((ret = ff_set_common_samplerates(ctx, rates)) < 0)
320  return ret;
321  layouts = ff_all_channel_counts();
322  if ((ret = ff_set_common_channel_layouts(ctx, layouts)) < 0)
323  return ret;
324  }
325  }
326 
327  return 0;
328 }
329 
331  .name = "streamselect",
332  .description = NULL_IF_CONFIG_SMALL("Select video streams"),
333  .init = init,
334  .query_formats = query_formats,
335  .process_command = process_command,
336  .uninit = uninit,
337  .activate = activate,
338  .priv_size = sizeof(StreamSelectContext),
339  .priv_class = &streamselect_class,
341 };
342 
343 #define astreamselect_options streamselect_options
344 AVFILTER_DEFINE_CLASS(astreamselect);
345 
347  .name = "astreamselect",
348  .description = NULL_IF_CONFIG_SMALL("Select audio streams"),
349  .init = init,
350  .query_formats = query_formats,
351  .process_command = process_command,
352  .uninit = uninit,
353  .activate = activate,
354  .priv_size = sizeof(StreamSelectContext),
355  .priv_class = &astreamselect_class,
357 };
#define NULL
Definition: coverity.c:32
static int process_command(AVFilterContext *ctx, const char *cmd, const char *args, char *res, int res_len, int flags)
This structure describes decoded (raw) audio or video data.
Definition: frame.h:308
static av_cold void uninit(AVFilterContext *ctx)
static int parse_definition(AVFilterContext *ctx, int nb_pads, int is_input, int is_audio)
AVOption.
Definition: opt.h:248
static int query_formats(AVFilterContext *ctx)
static av_cold int init(AVFilterContext *ctx)
Main libavfilter public API header.
#define AVFILTER_FLAG_DYNAMIC_INPUTS
The number of the filter inputs is not determined just by AVFilter.inputs.
Definition: avfilter.h:106
enum AVMediaType type
AVFilterPad type.
Definition: internal.h:65
#define FF_OUTLINK_IDX(link)
Definition: internal.h:303
int ff_set_common_channel_layouts(AVFilterContext *ctx, AVFilterChannelLayouts *channel_layouts)
A helper for query_formats() which sets all links to the same list of channel layouts/sample rates...
Definition: formats.c:569
int ff_framesync_configure(FFFrameSync *fs)
Configure a frame sync structure.
Definition: framesync.c:124
int64_t pts
Timestamp of the current event.
Definition: framesync.h:167
enum FFFrameSyncExtMode before
Extrapolation mode for timestamps before the first frame.
Definition: framesync.h:86
void * av_calloc(size_t nmemb, size_t size)
Non-inlined equivalent of av_mallocz_array().
Definition: mem.c:245
AVFilter ff_vf_streamselect
const char * name
Pad name.
Definition: internal.h:60
AVFilterContext * parent
Parent filter context.
Definition: framesync.h:152
AVFilterLink ** inputs
array of pointers to input links
Definition: avfilter.h:349
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1091
AVFilterPad * output_pads
array of output pads
Definition: avfilter.h:352
#define av_cold
Definition: attributes.h:88
AVOptions.
int64_t pts
Presentation timestamp in time_base units (time when frame should be shown to user).
Definition: frame.h:401
FFFrameSyncIn * in
Pointer to array of inputs.
Definition: framesync.h:203
int avfilter_config_links(AVFilterContext *filter)
Negotiate the media format, dimensions, etc of all inputs to a filter.
Definition: avfilter.c:277
#define AV_LOG_VERBOSE
Detailed information.
Definition: log.h:210
static int config_output(AVFilterLink *outlink)
enum FFFrameSyncExtMode after
Extrapolation mode for timestamps after the last frame.
Definition: framesync.h:91
#define AVFILTER_FLAG_DYNAMIC_OUTPUTS
The number of the filter outputs is not determined just by AVFilter.outputs.
Definition: avfilter.h:112
Input stream structure.
Definition: framesync.h:81
#define av_log(a,...)
AVFilterFormats * ff_all_formats(enum AVMediaType type)
Return a list of all formats supported by FFmpeg for the given media type.
Definition: formats.c:346
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
AVFilterPad * input_pads
array of input pads
Definition: avfilter.h:348
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
int ff_set_common_formats(AVFilterContext *ctx, AVFilterFormats *formats)
A helper for query_formats() which sets all links to the same list of formats.
Definition: formats.c:588
void ff_framesync_uninit(FFFrameSync *fs)
Free all memory currently allocated.
Definition: framesync.c:290
Frame sync structure.
Definition: framesync.h:146
unsigned nb_outputs
number of output pads
Definition: avfilter.h:354
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:153
void * priv
private data for use by the filter
Definition: avfilter.h:356
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:215
AVRational time_base
Time base for the incoming frames.
Definition: framesync.h:96
int ff_framesync_activate(FFFrameSync *fs)
Examine the frames in the filter&#39;s input and try to produce output.
Definition: framesync.c:341
int(* on_event)(struct FFFrameSync *fs)
Callback called when a frame event is ready.
Definition: framesync.h:172
char * av_asprintf(const char *fmt,...)
Definition: avstring.c:113
common internal API header
int(* config_props)(AVFilterLink *link)
Link configuration callback.
Definition: internal.h:118
static int activate(AVFilterContext *ctx)
unsigned nb_inputs
number of input pads
Definition: avfilter.h:350
AVFormatContext * ctx
Definition: movenc.c:48
AVRational time_base
Time base for the output events.
Definition: framesync.h:162
#define s(width, name)
Definition: cbs_vp9.c:257
void * opaque
Opaque pointer, not used by the API.
Definition: framesync.h:177
AVFrame * av_frame_clone(const AVFrame *src)
Create a new frame that references the same data as src.
Definition: frame.c:553
A list of supported channel layouts.
Definition: formats.h:86
static int parse_mapping(AVFilterContext *ctx, const char *map)
int ff_framesync_init(FFFrameSync *fs, AVFilterContext *parent, unsigned nb_in)
Initialize a frame sync structure.
Definition: framesync.c:84
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)\n", len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt));return ff_convert_dither(ac-> in
unsigned sync
Synchronization level: frames on input at the highest sync level will generate output frame events...
Definition: framesync.h:139
Describe the class of an AVClass context structure.
Definition: log.h:67
Filter definition.
Definition: avfilter.h:145
#define FLAGS
const char * name
Filter name.
Definition: avfilter.h:149
AVFilterLink ** outputs
array of pointers to output links
Definition: avfilter.h:353
enum MovChannelLayoutTag * layouts
Definition: mov_chan.c:434
AVFilterFormats * ff_all_samplerates(void)
Definition: formats.c:422
#define flags(name, subs,...)
Definition: cbs_av1.c:560
#define OFFSET(x)
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
void ff_filter_set_ready(AVFilterContext *filter, unsigned priority)
Mark a filter ready and schedule it for activation.
Definition: avfilter.c:193
AVFilter ff_af_astreamselect
#define TFLAGS
Completely stop all streams with this one.
Definition: framesync.h:65
#define av_free(p)
static int process_frame(FFFrameSync *fs)
A list of supported formats for one end of a filter link.
Definition: formats.h:65
An instance of a filter.
Definition: avfilter.h:341
FILE * out
Definition: movenc.c:54
#define av_freep(p)
static const AVOption streamselect_options[]
formats
Definition: signature.h:48
internal API functions
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
AVFilterChannelLayouts * ff_all_channel_counts(void)
Construct an AVFilterChannelLayouts coding for any channel layout, with known or unknown disposition...
Definition: formats.c:437
int ff_framesync_get_frame(FFFrameSync *fs, unsigned in, AVFrame **rframe, unsigned get)
Get the current frame in an input.
Definition: framesync.c:253
static const int rates[]
Definition: avresample.c:176
static int ff_insert_outpad(AVFilterContext *f, unsigned index, AVFilterPad *p)
Insert a new output pad for the filter.
Definition: internal.h:248
const AVFilter * filter
the AVFilter of which this is an instance
Definition: avfilter.h:344
int ff_set_common_samplerates(AVFilterContext *ctx, AVFilterFormats *samplerates)
Definition: formats.c:576
int i
Definition: input.c:407
AVFILTER_DEFINE_CLASS(streamselect)
static int ff_insert_inpad(AVFilterContext *f, unsigned index, AVFilterPad *p)
Insert a new input pad for the filter.
Definition: internal.h:240