FFmpeg
lavfi.c
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1 /*
2  * Copyright (c) 2011 Stefano Sabatini
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 /**
22  * @file
23  * libavfilter virtual input device
24  */
25 
26 /* #define DEBUG */
27 
28 #include <float.h> /* DBL_MIN, DBL_MAX */
29 
30 #include "libavutil/bprint.h"
32 #include "libavutil/file.h"
33 #include "libavutil/imgutils.h"
34 #include "libavutil/internal.h"
35 #include "libavutil/log.h"
36 #include "libavutil/mem.h"
37 #include "libavutil/opt.h"
38 #include "libavutil/parseutils.h"
39 #include "libavutil/pixdesc.h"
40 #include "libavfilter/avfilter.h"
41 #include "libavfilter/buffersink.h"
43 #include "libavformat/internal.h"
44 #include "avdevice.h"
45 
46 typedef struct {
47  AVClass *class; ///< class for private options
48  char *graph_str;
50  char *dump_graph;
54  int *sink_eof;
57  int nb_sinks;
59 } LavfiContext;
60 
62 {
63  LavfiContext *lavfi = avctx->priv_data;
64 
65  av_freep(&lavfi->sink_stream_map);
66  av_freep(&lavfi->sink_eof);
67  av_freep(&lavfi->stream_sink_map);
69  av_freep(&lavfi->sinks);
70  avfilter_graph_free(&lavfi->graph);
71 
72  return 0;
73 }
74 
76 {
77  LavfiContext *lavfi = avctx->priv_data;
78  AVStream *st;
79  int stream_idx, sink_idx;
80  AVRational *time_base;
81 
82  for (stream_idx = 0; stream_idx < lavfi->nb_sinks; stream_idx++) {
83  sink_idx = lavfi->stream_sink_map[stream_idx];
84  if (lavfi->sink_stream_subcc_map[sink_idx]) {
85  lavfi->sink_stream_subcc_map[sink_idx] = avctx->nb_streams;
86  if (!(st = avformat_new_stream(avctx, NULL)))
87  return AVERROR(ENOMEM);
90  time_base = &avctx->streams[stream_idx]->time_base;
91  st->time_base.num = time_base->num;
92  st->time_base.den = time_base->den;
93  } else {
94  lavfi->sink_stream_subcc_map[sink_idx] = -1;
95  }
96  }
97  return 0;
98 }
99 
101 {
102  LavfiContext *lavfi = avctx->priv_data;
103  AVFilterInOut *input_links = NULL, *output_links = NULL, *inout;
104  const AVFilter *buffersink, *abuffersink;
105  enum AVMediaType type;
106  int ret = 0, i, n;
107 
108 #define FAIL(ERR) { ret = ERR; goto end; }
109 
110  buffersink = avfilter_get_by_name("buffersink");
111  abuffersink = avfilter_get_by_name("abuffersink");
112 
113  if (lavfi->graph_filename && lavfi->graph_str) {
114  av_log(avctx, AV_LOG_ERROR,
115  "Only one of the graph or graph_file options must be specified\n");
116  FAIL(AVERROR(EINVAL));
117  }
118 
119  if (lavfi->graph_filename) {
120  AVBPrint graph_file_pb;
121  AVIOContext *avio = NULL;
123  if (avctx->protocol_whitelist && (ret = av_dict_set(&options, "protocol_whitelist", avctx->protocol_whitelist, 0)) < 0)
124  goto end;
127  if (ret < 0)
128  goto end;
129  av_bprint_init(&graph_file_pb, 0, AV_BPRINT_SIZE_UNLIMITED);
130  ret = avio_read_to_bprint(avio, &graph_file_pb, INT_MAX);
131  avio_closep(&avio);
132  if (ret) {
133  av_bprint_finalize(&graph_file_pb, NULL);
134  goto end;
135  }
136  if ((ret = av_bprint_finalize(&graph_file_pb, &lavfi->graph_str)))
137  goto end;
138  }
139 
140  if (!lavfi->graph_str)
141  lavfi->graph_str = av_strdup(avctx->url);
142 
143  /* parse the graph, create a stream for each open output */
144  if (!(lavfi->graph = avfilter_graph_alloc()))
145  FAIL(AVERROR(ENOMEM));
146 
147  if ((ret = avfilter_graph_parse_ptr(lavfi->graph, lavfi->graph_str,
148  &input_links, &output_links, avctx)) < 0)
149  goto end;
150 
151  if (input_links) {
152  av_log(avctx, AV_LOG_ERROR,
153  "Open inputs in the filtergraph are not acceptable\n");
154  FAIL(AVERROR(EINVAL));
155  }
156 
157  /* count the outputs */
158  for (n = 0, inout = output_links; inout; n++, inout = inout->next);
159  lavfi->nb_sinks = n;
160 
161  if (!(lavfi->sink_stream_map = av_malloc(sizeof(int) * n)))
162  FAIL(AVERROR(ENOMEM));
163  if (!(lavfi->sink_eof = av_mallocz(sizeof(int) * n)))
164  FAIL(AVERROR(ENOMEM));
165  if (!(lavfi->stream_sink_map = av_malloc(sizeof(int) * n)))
166  FAIL(AVERROR(ENOMEM));
167  if (!(lavfi->sink_stream_subcc_map = av_malloc(sizeof(int) * n)))
168  FAIL(AVERROR(ENOMEM));
169 
170  for (i = 0; i < n; i++)
171  lavfi->stream_sink_map[i] = -1;
172 
173  /* parse the output link names - they need to be of the form out0, out1, ...
174  * create a mapping between them and the streams */
175  for (i = 0, inout = output_links; inout; i++, inout = inout->next) {
176  int stream_idx = 0, suffix = 0, use_subcc = 0;
177  sscanf(inout->name, "out%n%d%n", &suffix, &stream_idx, &suffix);
178  if (!suffix) {
179  av_log(avctx, AV_LOG_ERROR,
180  "Invalid outpad name '%s'\n", inout->name);
181  FAIL(AVERROR(EINVAL));
182  }
183  if (inout->name[suffix]) {
184  if (!strcmp(inout->name + suffix, "+subcc")) {
185  use_subcc = 1;
186  } else {
187  av_log(avctx, AV_LOG_ERROR,
188  "Invalid outpad suffix '%s'\n", inout->name);
189  FAIL(AVERROR(EINVAL));
190  }
191  }
192 
193  if ((unsigned)stream_idx >= n) {
194  av_log(avctx, AV_LOG_ERROR,
195  "Invalid index was specified in output '%s', "
196  "must be a non-negative value < %d\n",
197  inout->name, n);
198  FAIL(AVERROR(EINVAL));
199  }
200 
201  if (lavfi->stream_sink_map[stream_idx] != -1) {
202  av_log(avctx, AV_LOG_ERROR,
203  "An output with stream index %d was already specified\n",
204  stream_idx);
205  FAIL(AVERROR(EINVAL));
206  }
207  lavfi->sink_stream_map[i] = stream_idx;
208  lavfi->stream_sink_map[stream_idx] = i;
209  lavfi->sink_stream_subcc_map[i] = !!use_subcc;
210  }
211 
212  /* for each open output create a corresponding stream */
213  for (i = 0, inout = output_links; inout; i++, inout = inout->next) {
214  AVStream *st;
215  if (!(st = avformat_new_stream(avctx, NULL)))
216  FAIL(AVERROR(ENOMEM));
217  st->id = i;
218  }
219 
220  /* create a sink for each output and connect them to the graph */
221  lavfi->sinks = av_malloc_array(lavfi->nb_sinks, sizeof(AVFilterContext *));
222  if (!lavfi->sinks)
223  FAIL(AVERROR(ENOMEM));
224 
225  for (i = 0, inout = output_links; inout; i++, inout = inout->next) {
226  AVFilterContext *sink;
227 
228  type = avfilter_pad_get_type(inout->filter_ctx->output_pads, inout->pad_idx);
229 
230  if (type == AVMEDIA_TYPE_VIDEO && ! buffersink ||
231  type == AVMEDIA_TYPE_AUDIO && ! abuffersink) {
232  av_log(avctx, AV_LOG_ERROR, "Missing required buffersink filter, aborting.\n");
234  }
235 
236  if (type == AVMEDIA_TYPE_VIDEO) {
237  ret = avfilter_graph_create_filter(&sink, buffersink,
238  inout->name, NULL,
239  NULL, lavfi->graph);
240  if (ret < 0)
241  goto end;
242  } else if (type == AVMEDIA_TYPE_AUDIO) {
243  static const enum AVSampleFormat sample_fmts[] = {
246  };
247 
248  ret = avfilter_graph_create_filter(&sink, abuffersink,
249  inout->name, NULL,
250  NULL, lavfi->graph);
251  if (ret >= 0)
252  ret = av_opt_set_bin(sink, "sample_fmts", (const uint8_t*)sample_fmts,
254  if (ret < 0)
255  goto end;
256  ret = av_opt_set_int(sink, "all_channel_counts", 1,
258  if (ret < 0)
259  goto end;
260  } else {
261  av_log(avctx, AV_LOG_ERROR,
262  "Output '%s' is not a video or audio output, not yet supported\n", inout->name);
263  FAIL(AVERROR(EINVAL));
264  }
265 
266  lavfi->sinks[i] = sink;
267  if ((ret = avfilter_link(inout->filter_ctx, inout->pad_idx, sink, 0)) < 0)
268  goto end;
269  }
270 
271  /* configure the graph */
272  if ((ret = avfilter_graph_config(lavfi->graph, avctx)) < 0)
273  goto end;
274 
275  if (lavfi->dump_graph) {
276  char *dump = avfilter_graph_dump(lavfi->graph, lavfi->dump_graph);
277  if (dump != NULL) {
278  fputs(dump, stderr);
279  fflush(stderr);
280  av_free(dump);
281  } else {
282  FAIL(AVERROR(ENOMEM));
283  }
284  }
285 
286  /* fill each stream with the information in the corresponding sink */
287  for (i = 0; i < lavfi->nb_sinks; i++) {
288  AVFilterContext *sink = lavfi->sinks[lavfi->stream_sink_map[i]];
289  AVRational time_base = av_buffersink_get_time_base(sink);
290  AVRational frame_rate = av_buffersink_get_frame_rate(sink);
291  AVStream *st = avctx->streams[i];
292  AVCodecParameters *const par = st->codecpar;
293  avpriv_set_pts_info(st, 64, time_base.num, time_base.den);
294  par->codec_type = av_buffersink_get_type(sink);
295  if (par->codec_type == AVMEDIA_TYPE_VIDEO) {
297  par->format = av_buffersink_get_format(sink);
298  par->width = av_buffersink_get_w(sink);
299  par->height = av_buffersink_get_h(sink);
300  avctx->probesize = FFMAX(avctx->probesize, sizeof(AVFrame) * 30);
301  st ->sample_aspect_ratio =
303  if (frame_rate.num > 0 && frame_rate.den > 0) {
304  st->avg_frame_rate = frame_rate;
305  st->r_frame_rate = frame_rate;
306  }
307  } else if (par->codec_type == AVMEDIA_TYPE_AUDIO) {
310  if (ret < 0)
311  goto end;
312  par->format = av_buffersink_get_format(sink);
313  par->codec_id = av_get_pcm_codec(par->format, -1);
314  if (par->codec_id == AV_CODEC_ID_NONE)
315  av_log(avctx, AV_LOG_ERROR,
316  "Could not find PCM codec for sample format %s.\n",
318  }
319  }
320 
321  if ((ret = create_subcc_streams(avctx)) < 0)
322  goto end;
323 
324 end:
325  avfilter_inout_free(&input_links);
326  avfilter_inout_free(&output_links);
327  return ret;
328 }
329 
331  int sink_idx)
332 {
333  LavfiContext *lavfi = avctx->priv_data;
334  AVFrameSideData *sd;
335  int stream_idx, ret;
336 
337  if ((stream_idx = lavfi->sink_stream_subcc_map[sink_idx]) < 0)
338  return 0;
340  return 0;
341  if ((ret = av_new_packet(&lavfi->subcc_packet, sd->size)) < 0)
342  return ret;
343  memcpy(lavfi->subcc_packet.data, sd->data, sd->size);
344  lavfi->subcc_packet.stream_index = stream_idx;
345  lavfi->subcc_packet.pts = frame->pts;
346  lavfi->subcc_packet.pos = frame->pkt_pos;
347  return 0;
348 }
349 
350 static void lavfi_free_frame(void *opaque, uint8_t *data)
351 {
352  AVFrame *frame = (AVFrame*)data;
354 }
355 
357 {
358  LavfiContext *lavfi = avctx->priv_data;
359  double min_pts = DBL_MAX;
360  int stream_idx, min_pts_sink_idx = 0;
361  AVFrame *frame;
362  AVDictionary *frame_metadata;
363  int ret, i;
364  AVStream *st;
365 
366  if (lavfi->subcc_packet.size) {
368  return pkt->size;
369  }
370 
371  frame = av_frame_alloc();
372  if (!frame)
373  return AVERROR(ENOMEM);
374 
375  /* iterate through all the graph sinks. Select the sink with the
376  * minimum PTS */
377  for (i = 0; i < lavfi->nb_sinks; i++) {
379  double d;
380 
381  if (lavfi->sink_eof[i])
382  continue;
383 
386  if (ret == AVERROR_EOF) {
387  ff_dlog(avctx, "EOF sink_idx:%d\n", i);
388  lavfi->sink_eof[i] = 1;
389  continue;
390  } else if (ret < 0)
391  goto fail;
393  ff_dlog(avctx, "sink_idx:%d time:%f\n", i, d);
395 
396  if (d < min_pts) {
397  min_pts = d;
398  min_pts_sink_idx = i;
399  }
400  }
401  if (min_pts == DBL_MAX) {
402  ret = AVERROR_EOF;
403  goto fail;
404  }
405 
406  ff_dlog(avctx, "min_pts_sink_idx:%i\n", min_pts_sink_idx);
407 
408  av_buffersink_get_frame_flags(lavfi->sinks[min_pts_sink_idx], frame, 0);
409  stream_idx = lavfi->sink_stream_map[min_pts_sink_idx];
410  st = avctx->streams[stream_idx];
411 
412  if (st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) {
413  pkt->buf = av_buffer_create((uint8_t*)frame, sizeof(*frame),
414  &lavfi_free_frame, NULL, 0);
415  if (!pkt->buf) {
416  ret = AVERROR(ENOMEM);
417  goto fail;
418  }
419 
420  pkt->data = pkt->buf->data;
421  pkt->size = pkt->buf->size;
423  } else if (st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) {
424  int size = frame->nb_samples * av_get_bytes_per_sample(frame->format) *
425  frame->ch_layout.nb_channels;
426  if ((ret = av_new_packet(pkt, size)) < 0)
427  goto fail;
428  memcpy(pkt->data, frame->data[0], size);
429  }
430 
431  frame_metadata = frame->metadata;
432  if (frame_metadata) {
433  size_t size;
434  uint8_t *metadata = av_packet_pack_dictionary(frame_metadata, &size);
435 
436  if (!metadata) {
437  ret = AVERROR(ENOMEM);
438  goto fail;
439  }
441  metadata, size)) < 0) {
442  av_freep(&metadata);
443  goto fail;
444  }
445  }
446 
447  if ((ret = create_subcc_packet(avctx, frame, min_pts_sink_idx)) < 0) {
448  goto fail;
449  }
450 
451  pkt->stream_index = stream_idx;
452  pkt->pts = frame->pts;
453  pkt->pos = frame->pkt_pos;
454 
457 
458  return pkt->size;
459 fail:
461  return ret;
462 
463 }
464 
465 #define OFFSET(x) offsetof(LavfiContext, x)
466 
467 #define DEC AV_OPT_FLAG_DECODING_PARAM
468 
469 static const AVOption options[] = {
470  { "graph", "set libavfilter graph", OFFSET(graph_str), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
471  { "graph_file","set libavfilter graph filename", OFFSET(graph_filename), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC},
472  { "dumpgraph", "dump graph to stderr", OFFSET(dump_graph), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
473  { NULL },
474 };
475 
476 static const AVClass lavfi_class = {
477  .class_name = "lavfi indev",
478  .item_name = av_default_item_name,
479  .option = options,
480  .version = LIBAVUTIL_VERSION_INT,
481  .category = AV_CLASS_CATEGORY_DEVICE_INPUT,
482 };
483 
485  .name = "lavfi",
486  .long_name = NULL_IF_CONFIG_SMALL("Libavfilter virtual input device"),
487  .priv_data_size = sizeof(LavfiContext),
491  .flags = AVFMT_NOFILE,
492  .priv_class = &lavfi_class,
493  .flags_internal = FF_FMT_INIT_CLEANUP,
494 };
AV_CODEC_ID_EIA_608
@ AV_CODEC_ID_EIA_608
Definition: codec_id.h:539
AVMEDIA_TYPE_SUBTITLE
@ AVMEDIA_TYPE_SUBTITLE
Definition: avutil.h:204
AV_BPRINT_SIZE_UNLIMITED
#define AV_BPRINT_SIZE_UNLIMITED
av_buffersink_get_ch_layout
int av_buffersink_get_ch_layout(const AVFilterContext *ctx, AVChannelLayout *out)
Definition: buffersink.c:241
av_buffersink_get_sample_aspect_ratio
AVRational av_buffersink_get_sample_aspect_ratio(const AVFilterContext *ctx)
lavfi_read_header
static av_cold int lavfi_read_header(AVFormatContext *avctx)
Definition: lavfi.c:100
FF_FMT_INIT_CLEANUP
#define FF_FMT_INIT_CLEANUP
For an AVInputFormat with this flag set read_close() needs to be called by the caller upon read_heade...
Definition: internal.h:48
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
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: options.c:237
LavfiContext::stream_sink_map
int * stream_sink_map
Definition: lavfi.c:55
lavfi_free_frame
static void lavfi_free_frame(void *opaque, uint8_t *data)
Definition: lavfi.c:350
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:57
FAIL
#define FAIL(ERR)
LavfiContext::graph_str
char * graph_str
Definition: lavfi.c:48
av_bprint_finalize
int av_bprint_finalize(AVBPrint *buf, char **ret_str)
Finalize a print buffer.
Definition: bprint.c:235
av_bprint_init
void av_bprint_init(AVBPrint *buf, unsigned size_init, unsigned size_max)
Definition: bprint.c:69
av_frame_get_side_data
AVFrameSideData * av_frame_get_side_data(const AVFrame *frame, enum AVFrameSideDataType type)
Definition: frame.c:691
AVCodecParameters
This struct describes the properties of an encoded stream.
Definition: codec_par.h:53
sample_fmts
static enum AVSampleFormat sample_fmts[]
Definition: adpcmenc.c:947
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
AVBufferRef::data
uint8_t * data
The data buffer.
Definition: buffer.h:90
LavfiContext::nb_sinks
int nb_sinks
Definition: lavfi.c:57
AV_FRAME_DATA_A53_CC
@ AV_FRAME_DATA_A53_CC
ATSC A53 Part 4 Closed Captions.
Definition: frame.h:59
av_buffersink_get_frame_flags
int attribute_align_arg av_buffersink_get_frame_flags(AVFilterContext *ctx, AVFrame *frame, int flags)
Get a frame with filtered data from sink and put it in frame.
Definition: buffersink.c:146
create_subcc_packet
static int create_subcc_packet(AVFormatContext *avctx, AVFrame *frame, int sink_idx)
Definition: lavfi.c:330
AV_TIME_BASE_Q
#define AV_TIME_BASE_Q
Internal time base represented as fractional value.
Definition: avutil.h:260
av_frame_free
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:116
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:325
pixdesc.h
AVFormatContext::streams
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1281
AVPacket::data
uint8_t * data
Definition: packet.h:374
AVOption
AVOption.
Definition: opt.h:251
AVStream::avg_frame_rate
AVRational avg_frame_rate
Average framerate.
Definition: avformat.h:1028
data
const char data[16]
Definition: mxf.c:143
LavfiContext::dump_graph
char * dump_graph
Definition: lavfi.c:50
float.h
AVDictionary
Definition: dict.c:30
LavfiContext::graph
AVFilterGraph * graph
Definition: lavfi.c:51
FFMAX
#define FFMAX(a, b)
Definition: macros.h:47
AVFormatContext::probesize
int64_t probesize
Maximum number of bytes read from input in order to determine stream properties.
Definition: avformat.h:1368
AVFilter::name
const char * name
Filter name.
Definition: avfilter.h:175
lavfi_read_packet
static int lavfi_read_packet(AVFormatContext *avctx, AVPacket *pkt)
Definition: lavfi.c:356
av_malloc
#define av_malloc(s)
Definition: tableprint_vlc.h:30
avfilter_graph_free
void avfilter_graph_free(AVFilterGraph **graph)
Free a graph, destroy its links, and set *graph to NULL.
Definition: avfiltergraph.c:119
AVFormatContext::interrupt_callback
AVIOInterruptCB interrupt_callback
Custom interrupt callbacks for the I/O layer.
Definition: avformat.h:1480
avfilter_graph_create_filter
int avfilter_graph_create_filter(AVFilterContext **filt_ctx, const AVFilter *filt, const char *name, const char *args, void *opaque, AVFilterGraph *graph_ctx)
Create and add a filter instance into an existing graph.
Definition: avfiltergraph.c:138
avpriv_set_pts_info
void avpriv_set_pts_info(AVStream *st, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: avformat.c:697
avio_open2
int avio_open2(AVIOContext **s, const char *url, int flags, const AVIOInterruptCB *int_cb, AVDictionary **options)
Create and initialize a AVIOContext for accessing the resource indicated by url.
Definition: aviobuf.c:1249
av_packet_add_side_data
int av_packet_add_side_data(AVPacket *pkt, enum AVPacketSideDataType type, uint8_t *data, size_t size)
Wrap an existing array as a packet side data.
Definition: avpacket.c:196
LavfiContext::graph_filename
char * graph_filename
Definition: lavfi.c:49
fail
#define fail()
Definition: checkasm.h:131
avfilter_graph_alloc
AVFilterGraph * avfilter_graph_alloc(void)
Allocate a filter graph.
Definition: avfiltergraph.c:82
read_close
static av_cold int read_close(AVFormatContext *ctx)
Definition: libcdio.c:143
type
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf type
Definition: writing_filters.txt:86
AV_CLASS_CATEGORY_DEVICE_INPUT
@ AV_CLASS_CATEGORY_DEVICE_INPUT
Definition: log.h:45
AVRational::num
int num
Numerator.
Definition: rational.h:59
av_frame_alloc
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:104
AV_PKT_DATA_STRINGS_METADATA
@ AV_PKT_DATA_STRINGS_METADATA
A list of zero terminated key/value strings.
Definition: packet.h:173
avfilter_inout_free
void avfilter_inout_free(AVFilterInOut **inout)
Free the supplied list of AVFilterInOut and set *inout to NULL.
Definition: graphparser.c:212
pkt
AVPacket * pkt
Definition: movenc.c:59
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
AVFrameSideData::size
size_t size
Definition: frame.h:234
AVInputFormat
Definition: avformat.h:656
av_cold
#define av_cold
Definition: attributes.h:90
av_buffersink_get_frame_rate
AVRational av_buffersink_get_frame_rate(const AVFilterContext *ctx)
AV_BUFFERSINK_FLAG_PEEK
#define AV_BUFFERSINK_FLAG_PEEK
Tell av_buffersink_get_buffer_ref() to read video/samples buffer reference, but not remove it from th...
Definition: buffersink.h:88
LavfiContext::sink_stream_map
int * sink_stream_map
Definition: lavfi.c:53
LavfiContext
Definition: lavfi.c:46
av_new_packet
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:97
avio_read_to_bprint
int avio_read_to_bprint(AVIOContext *h, struct AVBPrint *pb, size_t max_size)
Read contents of h into print buffer, up to max_size bytes, or up to EOF.
Definition: aviobuf.c:1355
AVCodecParameters::sample_aspect_ratio
AVRational sample_aspect_ratio
Video only.
Definition: codec_par.h:137
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:661
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
AVCodecParameters::width
int width
Video only.
Definition: codec_par.h:127
lavfi_class
static const AVClass lavfi_class
Definition: lavfi.c:476
av_buffersink_get_format
int av_buffersink_get_format(const AVFilterContext *ctx)
av_buffersink_get_time_base
AVRational av_buffersink_get_time_base(const AVFilterContext *ctx)
options
static const AVOption options[]
Definition: lavfi.c:469
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
AV_CODEC_ID_WRAPPED_AVFRAME
@ AV_CODEC_ID_WRAPPED_AVFRAME
Passthrough codec, AVFrames wrapped in AVPacket.
Definition: codec_id.h:579
AVFormatContext
Format I/O context.
Definition: avformat.h:1213
avfilter_get_by_name
const AVFilter * avfilter_get_by_name(const char *name)
Get a filter definition matching the given name.
Definition: allfilters.c:596
internal.h
AVPacket::buf
AVBufferRef * buf
A reference to the reference-counted buffer where the packet data is stored.
Definition: packet.h:357
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1108
LIBAVUTIL_VERSION_INT
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:532
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
avfilter_graph_config
int avfilter_graph_config(AVFilterGraph *graphctx, void *log_ctx)
Check validity and configure all the links and formats in the graph.
Definition: avfiltergraph.c:1167
AVStream::time_base
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented.
Definition: avformat.h:978
NULL
#define NULL
Definition: coverity.c:32
av_opt_set_bin
int av_opt_set_bin(void *obj, const char *name, const uint8_t *val, int len, int search_flags)
Definition: opt.c:639
DEC
#define DEC
Definition: lavfi.c:467
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
AVFormatContext::protocol_whitelist
char * protocol_whitelist
',' separated list of allowed protocols.
Definition: avformat.h:1751
av_default_item_name
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:237
parseutils.h
AV_ROUND_NEAR_INF
@ AV_ROUND_NEAR_INF
Round to nearest and halfway cases away from zero.
Definition: mathematics.h:84
AVFilterGraph
Definition: avfilter.h:871
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:212
av_packet_move_ref
void av_packet_move_ref(AVPacket *dst, AVPacket *src)
Move every field in src to dst and reset src.
Definition: avpacket.c:479
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:177
av_opt_set_int
int av_opt_set_int(void *obj, const char *name, int64_t val, int search_flags)
Definition: opt.c:624
av_buffer_create
AVBufferRef * av_buffer_create(uint8_t *data, size_t size, void(*free)(void *opaque, uint8_t *data), void *opaque, int flags)
Create an AVBuffer from an existing array.
Definition: buffer.c:55
ff_lavfi_demuxer
const AVInputFormat ff_lavfi_demuxer
Definition: lavfi.c:484
AVFormatContext::nb_streams
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition: avformat.h:1269
ff_dlog
#define ff_dlog(a,...)
Definition: tableprint_vlc.h:28
AVIOContext
Bytestream IO Context.
Definition: avio.h:162
OFFSET
#define OFFSET(x)
Definition: lavfi.c:465
AVMediaType
AVMediaType
Definition: avutil.h:199
AVPacket::size
int size
Definition: packet.h:375
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
for
for(k=2;k<=8;++k)
Definition: h264pred_template.c:425
avfilter_link
int avfilter_link(AVFilterContext *src, unsigned srcpad, AVFilterContext *dst, unsigned dstpad)
Link two filters together.
Definition: avfilter.c:140
AVFormatContext::url
char * url
input or output URL.
Definition: avformat.h:1296
size
int size
Definition: twinvq_data.h:10344
AVFrameSideData::data
uint8_t * data
Definition: frame.h:233
AVFMT_NOFILE
#define AVFMT_NOFILE
Demuxer will use avio_open, no opened file should be provided by the caller.
Definition: avformat.h:470
LavfiContext::sinks
AVFilterContext ** sinks
Definition: lavfi.c:52
AVStream::sample_aspect_ratio
AVRational sample_aspect_ratio
sample aspect ratio (0 if unknown)
Definition: avformat.h:1017
avdevice.h
AV_OPT_SEARCH_CHILDREN
#define AV_OPT_SEARCH_CHILDREN
Search in possible children of the given object first.
Definition: opt.h:563
LavfiContext::sink_stream_subcc_map
int * sink_stream_subcc_map
Definition: lavfi.c:56
av_packet_pack_dictionary
uint8_t * av_packet_pack_dictionary(AVDictionary *dict, size_t *size)
Pack a dictionary for use in side_data.
Definition: avpacket.c:307
AVPacket::flags
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:380
av_dict_free
void av_dict_free(AVDictionary **pm)
Free all the memory allocated for an AVDictionary struct and all keys and values.
Definition: dict.c:203
av_buffersink_get_type
enum AVMediaType av_buffersink_get_type(const AVFilterContext *ctx)
AVBufferRef::size
size_t size
Size of data in bytes.
Definition: buffer.h:94
buffersink.h
LavfiContext::subcc_packet
AVPacket subcc_packet
Definition: lavfi.c:58
av_buffersink_get_w
int av_buffersink_get_w(const AVFilterContext *ctx)
avio_closep
int avio_closep(AVIOContext **s)
Close the resource accessed by the AVIOContext *s, free it and set the pointer pointing to it to NULL...
Definition: aviobuf.c:1288
create_subcc_streams
static int create_subcc_streams(AVFormatContext *avctx)
Definition: lavfi.c:75
bprint.h
log.h
AV_CODEC_ID_NONE
@ AV_CODEC_ID_NONE
Definition: codec_id.h:48
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:269
AVPacket::pts
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:367
avio_internal.h
av_get_bytes_per_sample
int av_get_bytes_per_sample(enum AVSampleFormat sample_fmt)
Return number of bytes per sample.
Definition: samplefmt.c:108
avfilter_graph_parse_ptr
int avfilter_graph_parse_ptr(AVFilterGraph *graph, const char *filters, AVFilterInOut **inputs, AVFilterInOut **outputs, void *log_ctx)
Add a graph described by a string to a graph.
Definition: graphparser.c:549
internal.h
AV_SAMPLE_FMT_U8
@ AV_SAMPLE_FMT_U8
unsigned 8 bits
Definition: samplefmt.h:57
AVCodecParameters::height
int height
Definition: codec_par.h:128
av_malloc_array
#define av_malloc_array(a, b)
Definition: tableprint_vlc.h:31
AVSampleFormat
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:55
av_frame_unref
void av_frame_unref(AVFrame *frame)
Unreference all the buffers referenced by frame and reset the frame fields.
Definition: frame.c:487
AV_SAMPLE_FMT_S16
@ AV_SAMPLE_FMT_S16
signed 16 bits
Definition: samplefmt.h:58
tb
#define tb
Definition: regdef.h:68
av_mallocz
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:264
av_buffersink_get_h
int av_buffersink_get_h(const AVFilterContext *ctx)
AVFilter
Filter definition.
Definition: avfilter.h:171
AVStream::id
int id
Format-specific stream ID.
Definition: avformat.h:962
ret
ret
Definition: filter_design.txt:187
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
AVStream
Stream structure.
Definition: avformat.h:948
LavfiContext::sink_eof
int * sink_eof
Definition: lavfi.c:54
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:71
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
avfilter_graph_dump
char * avfilter_graph_dump(AVFilterGraph *graph, const char *options)
Dump a graph into a human-readable string representation.
Definition: graphdump.c:157
avfilter_pad_get_type
enum AVMediaType avfilter_pad_get_type(const AVFilterPad *pads, int pad_idx)
Get the type of an AVFilterPad.
Definition: avfilter.c:958
suffix
const char * suffix
Definition: checkasm.c:211
lavfi_read_close
static av_cold int lavfi_read_close(AVFormatContext *avctx)
Definition: lavfi.c:61
channel_layout.h
av_buffersink_get_sample_rate
int av_buffersink_get_sample_rate(const AVFilterContext *ctx)
AVRational::den
int den
Denominator.
Definition: rational.h:60
avfilter.h
AVStream::r_frame_rate
AVRational r_frame_rate
Real base framerate of the stream.
Definition: avformat.h:1097
file.h
AVPacket::stream_index
int stream_index
Definition: packet.h:376
AVERROR_FILTER_NOT_FOUND
#define AVERROR_FILTER_NOT_FOUND
Filter not found.
Definition: error.h:60
AVFilterContext
An instance of a filter.
Definition: avfilter.h:408
av_get_pcm_codec
enum AVCodecID av_get_pcm_codec(enum AVSampleFormat fmt, int be)
Return the PCM codec associated with a sample format.
Definition: utils.c:564
AVIO_FLAG_READ
#define AVIO_FLAG_READ
read-only
Definition: avio.h:628
av_strdup
char * av_strdup(const char *s)
Duplicate a string.
Definition: mem.c:280
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
mem.h
AVFrameSideData
Structure to hold side data for an AVFrame.
Definition: frame.h:231
AVCodecParameters::format
int format
Definition: codec_par.h:85
av_free
#define av_free(p)
Definition: tableprint_vlc.h:33
AV_ROUND_PASS_MINMAX
@ AV_ROUND_PASS_MINMAX
Flag telling rescaling functions to pass INT64_MIN/MAX through unchanged, avoiding special cases for ...
Definition: mathematics.h:108
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:61
AVPacket
This structure stores compressed data.
Definition: packet.h:351
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:34
av_dict_set
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
AVPacket::pos
int64_t pos
byte position in stream, -1 if unknown
Definition: packet.h:394
d
d
Definition: ffmpeg_filter.c:155
imgutils.h
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
AV_SAMPLE_FMT_DBL
@ AV_SAMPLE_FMT_DBL
double
Definition: samplefmt.h:61
AV_OPT_TYPE_STRING
@ AV_OPT_TYPE_STRING
Definition: opt.h:229
AV_SAMPLE_FMT_S32
@ AV_SAMPLE_FMT_S32
signed 32 bits
Definition: samplefmt.h:59
AVFilterInOut
A linked-list of the inputs/outputs of the filter chain.
Definition: avfilter.h:1031
AV_PKT_FLAG_TRUSTED
#define AV_PKT_FLAG_TRUSTED
The packet comes from a trusted source.
Definition: packet.h:443
AVFormatContext::priv_data
void * priv_data
Format private data.
Definition: avformat.h:1241
AV_SAMPLE_FMT_FLT
@ AV_SAMPLE_FMT_FLT
float
Definition: samplefmt.h:60
av_rescale_q_rnd
int64_t av_rescale_q_rnd(int64_t a, AVRational bq, AVRational cq, enum AVRounding rnd)
Rescale a 64-bit integer by 2 rational numbers with specified rounding.
Definition: mathematics.c:134