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;
58  int nb_sinks;
60 } LavfiContext;
61 
62 static int *create_all_formats(int n)
63 {
64  int i, j, *fmts, count = 0;
65 
66  for (i = 0; i < n; i++) {
68  if (!(desc->flags & AV_PIX_FMT_FLAG_HWACCEL))
69  count++;
70  }
71 
72  if (!(fmts = av_malloc_array(count + 1, sizeof(*fmts))))
73  return NULL;
74  for (j = 0, i = 0; i < n; i++) {
76  if (!(desc->flags & AV_PIX_FMT_FLAG_HWACCEL))
77  fmts[j++] = i;
78  }
79  fmts[j] = -1;
80  return fmts;
81 }
82 
84 {
85  LavfiContext *lavfi = avctx->priv_data;
86 
87  av_freep(&lavfi->sink_stream_map);
88  av_freep(&lavfi->sink_eof);
89  av_freep(&lavfi->stream_sink_map);
91  av_freep(&lavfi->sinks);
92  avfilter_graph_free(&lavfi->graph);
94 
95  return 0;
96 }
97 
99 {
100  LavfiContext *lavfi = avctx->priv_data;
101  AVStream *st;
102  int stream_idx, sink_idx;
103  AVRational *time_base;
104 
105  for (stream_idx = 0; stream_idx < lavfi->nb_sinks; stream_idx++) {
106  sink_idx = lavfi->stream_sink_map[stream_idx];
107  if (lavfi->sink_stream_subcc_map[sink_idx]) {
108  lavfi->sink_stream_subcc_map[sink_idx] = avctx->nb_streams;
109  if (!(st = avformat_new_stream(avctx, NULL)))
110  return AVERROR(ENOMEM);
113  time_base = &avctx->streams[stream_idx]->time_base;
114  st->time_base.num = time_base->num;
115  st->time_base.den = time_base->den;
116  } else {
117  lavfi->sink_stream_subcc_map[sink_idx] = -1;
118  }
119  }
120  return 0;
121 }
122 
124 {
125  LavfiContext *lavfi = avctx->priv_data;
126  AVFilterInOut *input_links = NULL, *output_links = NULL, *inout;
127  const AVFilter *buffersink, *abuffersink;
129  enum AVMediaType type;
130  int ret = 0, i, n;
131 
132 #define FAIL(ERR) { ret = ERR; goto end; }
133 
134  if (!pix_fmts)
135  FAIL(AVERROR(ENOMEM));
136 
137  buffersink = avfilter_get_by_name("buffersink");
138  abuffersink = avfilter_get_by_name("abuffersink");
139 
140  if (lavfi->graph_filename && lavfi->graph_str) {
141  av_log(avctx, AV_LOG_ERROR,
142  "Only one of the graph or graph_file options must be specified\n");
143  FAIL(AVERROR(EINVAL));
144  }
145 
146  if (lavfi->graph_filename) {
147  AVBPrint graph_file_pb;
148  AVIOContext *avio = NULL;
150  if (avctx->protocol_whitelist && (ret = av_dict_set(&options, "protocol_whitelist", avctx->protocol_whitelist, 0)) < 0)
151  goto end;
153  av_dict_set(&options, "protocol_whitelist", NULL, 0);
154  if (ret < 0)
155  goto end;
156  av_bprint_init(&graph_file_pb, 0, AV_BPRINT_SIZE_UNLIMITED);
157  ret = avio_read_to_bprint(avio, &graph_file_pb, INT_MAX);
158  avio_closep(&avio);
159  av_bprint_chars(&graph_file_pb, '\0', 1);
160  if (!ret && !av_bprint_is_complete(&graph_file_pb))
161  ret = AVERROR(ENOMEM);
162  if (ret) {
163  av_bprint_finalize(&graph_file_pb, NULL);
164  goto end;
165  }
166  if ((ret = av_bprint_finalize(&graph_file_pb, &lavfi->graph_str)))
167  goto end;
168  }
169 
170  if (!lavfi->graph_str)
171  lavfi->graph_str = av_strdup(avctx->url);
172 
173  /* parse the graph, create a stream for each open output */
174  if (!(lavfi->graph = avfilter_graph_alloc()))
175  FAIL(AVERROR(ENOMEM));
176 
177  if ((ret = avfilter_graph_parse_ptr(lavfi->graph, lavfi->graph_str,
178  &input_links, &output_links, avctx)) < 0)
179  goto end;
180 
181  if (input_links) {
182  av_log(avctx, AV_LOG_ERROR,
183  "Open inputs in the filtergraph are not acceptable\n");
184  FAIL(AVERROR(EINVAL));
185  }
186 
187  /* count the outputs */
188  for (n = 0, inout = output_links; inout; n++, inout = inout->next);
189  lavfi->nb_sinks = n;
190 
191  if (!(lavfi->sink_stream_map = av_malloc(sizeof(int) * n)))
192  FAIL(AVERROR(ENOMEM));
193  if (!(lavfi->sink_eof = av_mallocz(sizeof(int) * n)))
194  FAIL(AVERROR(ENOMEM));
195  if (!(lavfi->stream_sink_map = av_malloc(sizeof(int) * n)))
196  FAIL(AVERROR(ENOMEM));
197  if (!(lavfi->sink_stream_subcc_map = av_malloc(sizeof(int) * n)))
198  FAIL(AVERROR(ENOMEM));
199 
200  for (i = 0; i < n; i++)
201  lavfi->stream_sink_map[i] = -1;
202 
203  /* parse the output link names - they need to be of the form out0, out1, ...
204  * create a mapping between them and the streams */
205  for (i = 0, inout = output_links; inout; i++, inout = inout->next) {
206  int stream_idx = 0, suffix = 0, use_subcc = 0;
207  sscanf(inout->name, "out%n%d%n", &suffix, &stream_idx, &suffix);
208  if (!suffix) {
209  av_log(avctx, AV_LOG_ERROR,
210  "Invalid outpad name '%s'\n", inout->name);
211  FAIL(AVERROR(EINVAL));
212  }
213  if (inout->name[suffix]) {
214  if (!strcmp(inout->name + suffix, "+subcc")) {
215  use_subcc = 1;
216  } else {
217  av_log(avctx, AV_LOG_ERROR,
218  "Invalid outpad suffix '%s'\n", inout->name);
219  FAIL(AVERROR(EINVAL));
220  }
221  }
222 
223  if ((unsigned)stream_idx >= n) {
224  av_log(avctx, AV_LOG_ERROR,
225  "Invalid index was specified in output '%s', "
226  "must be a non-negative value < %d\n",
227  inout->name, n);
228  FAIL(AVERROR(EINVAL));
229  }
230 
231  if (lavfi->stream_sink_map[stream_idx] != -1) {
232  av_log(avctx, AV_LOG_ERROR,
233  "An output with stream index %d was already specified\n",
234  stream_idx);
235  FAIL(AVERROR(EINVAL));
236  }
237  lavfi->sink_stream_map[i] = stream_idx;
238  lavfi->stream_sink_map[stream_idx] = i;
239  lavfi->sink_stream_subcc_map[i] = !!use_subcc;
240  }
241 
242  /* for each open output create a corresponding stream */
243  for (i = 0, inout = output_links; inout; i++, inout = inout->next) {
244  AVStream *st;
245  if (!(st = avformat_new_stream(avctx, NULL)))
246  FAIL(AVERROR(ENOMEM));
247  st->id = i;
248  }
249 
250  /* create a sink for each output and connect them to the graph */
251  lavfi->sinks = av_malloc_array(lavfi->nb_sinks, sizeof(AVFilterContext *));
252  if (!lavfi->sinks)
253  FAIL(AVERROR(ENOMEM));
254 
255  for (i = 0, inout = output_links; inout; i++, inout = inout->next) {
256  AVFilterContext *sink;
257 
258  type = avfilter_pad_get_type(inout->filter_ctx->output_pads, inout->pad_idx);
259 
260  if (type == AVMEDIA_TYPE_VIDEO && ! buffersink ||
261  type == AVMEDIA_TYPE_AUDIO && ! abuffersink) {
262  av_log(avctx, AV_LOG_ERROR, "Missing required buffersink filter, aborting.\n");
264  }
265 
266  if (type == AVMEDIA_TYPE_VIDEO) {
267  ret = avfilter_graph_create_filter(&sink, buffersink,
268  inout->name, NULL,
269  NULL, lavfi->graph);
270  if (ret >= 0)
272  if (ret < 0)
273  goto end;
274  } else if (type == AVMEDIA_TYPE_AUDIO) {
279  AV_SAMPLE_FMT_DBL, -1 };
280 
281  ret = avfilter_graph_create_filter(&sink, abuffersink,
282  inout->name, NULL,
283  NULL, lavfi->graph);
284  if (ret >= 0)
286  if (ret < 0)
287  goto end;
288  ret = av_opt_set_int(sink, "all_channel_counts", 1,
290  if (ret < 0)
291  goto end;
292  } else {
293  av_log(avctx, AV_LOG_ERROR,
294  "Output '%s' is not a video or audio output, not yet supported\n", inout->name);
295  FAIL(AVERROR(EINVAL));
296  }
297 
298  lavfi->sinks[i] = sink;
299  if ((ret = avfilter_link(inout->filter_ctx, inout->pad_idx, sink, 0)) < 0)
300  goto end;
301  }
302 
303  /* configure the graph */
304  if ((ret = avfilter_graph_config(lavfi->graph, avctx)) < 0)
305  goto end;
306 
307  if (lavfi->dump_graph) {
308  char *dump = avfilter_graph_dump(lavfi->graph, lavfi->dump_graph);
309  if (dump != NULL) {
310  fputs(dump, stderr);
311  fflush(stderr);
312  av_free(dump);
313  } else {
314  FAIL(AVERROR(ENOMEM));
315  }
316  }
317 
318  /* fill each stream with the information in the corresponding sink */
319  for (i = 0; i < lavfi->nb_sinks; i++) {
320  AVFilterContext *sink = lavfi->sinks[lavfi->stream_sink_map[i]];
321  AVRational time_base = av_buffersink_get_time_base(sink);
322  AVStream *st = avctx->streams[i];
324  avpriv_set_pts_info(st, 64, time_base.num, time_base.den);
328  st->codecpar->width = av_buffersink_get_w(sink);
329  st->codecpar->height = av_buffersink_get_h(sink);
330  st ->sample_aspect_ratio =
332  avctx->probesize = FFMAX(avctx->probesize,
335  30);
336  } else if (av_buffersink_get_type(sink) == AVMEDIA_TYPE_AUDIO) {
342  if (st->codecpar->codec_id == AV_CODEC_ID_NONE)
343  av_log(avctx, AV_LOG_ERROR,
344  "Could not find PCM codec for sample format %s.\n",
346  }
347  }
348 
349  if ((ret = create_subcc_streams(avctx)) < 0)
350  goto end;
351 
352  if (!(lavfi->decoded_frame = av_frame_alloc()))
353  FAIL(AVERROR(ENOMEM));
354 
355 end:
356  av_free(pix_fmts);
357  avfilter_inout_free(&input_links);
358  avfilter_inout_free(&output_links);
359  if (ret < 0)
360  lavfi_read_close(avctx);
361  return ret;
362 }
363 
365  int sink_idx)
366 {
367  LavfiContext *lavfi = avctx->priv_data;
368  AVFrameSideData *sd;
369  int stream_idx, ret;
370 
371  if ((stream_idx = lavfi->sink_stream_subcc_map[sink_idx]) < 0)
372  return 0;
374  return 0;
375  if ((ret = av_new_packet(&lavfi->subcc_packet, sd->size)) < 0)
376  return ret;
377  memcpy(lavfi->subcc_packet.data, sd->data, sd->size);
378  lavfi->subcc_packet.stream_index = stream_idx;
379  lavfi->subcc_packet.pts = frame->pts;
380  lavfi->subcc_packet.pos = frame->pkt_pos;
381  return 0;
382 }
383 
385 {
386  LavfiContext *lavfi = avctx->priv_data;
387  double min_pts = DBL_MAX;
388  int stream_idx, min_pts_sink_idx = 0;
389  AVFrame *frame = lavfi->decoded_frame;
390  AVDictionary *frame_metadata;
391  int ret, i;
392  int size = 0;
393  AVStream *st;
394 
395  if (lavfi->subcc_packet.size) {
397  return pkt->size;
398  }
399 
400  /* iterate through all the graph sinks. Select the sink with the
401  * minimum PTS */
402  for (i = 0; i < lavfi->nb_sinks; i++) {
404  double d;
405  int ret;
406 
407  if (lavfi->sink_eof[i])
408  continue;
409 
412  if (ret == AVERROR_EOF) {
413  ff_dlog(avctx, "EOF sink_idx:%d\n", i);
414  lavfi->sink_eof[i] = 1;
415  continue;
416  } else if (ret < 0)
417  return ret;
419  ff_dlog(avctx, "sink_idx:%d time:%f\n", i, d);
421 
422  if (d < min_pts) {
423  min_pts = d;
424  min_pts_sink_idx = i;
425  }
426  }
427  if (min_pts == DBL_MAX)
428  return AVERROR_EOF;
429 
430  ff_dlog(avctx, "min_pts_sink_idx:%i\n", min_pts_sink_idx);
431 
432  av_buffersink_get_frame_flags(lavfi->sinks[min_pts_sink_idx], frame, 0);
433  stream_idx = lavfi->sink_stream_map[min_pts_sink_idx];
434  st = avctx->streams[stream_idx];
435 
436  if (st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) {
437  size = av_image_get_buffer_size(frame->format, frame->width, frame->height, 1);
438  if ((ret = av_new_packet(pkt, size)) < 0)
439  goto fail;
440 
441  av_image_copy_to_buffer(pkt->data, size, (const uint8_t **)frame->data, frame->linesize,
442  frame->format, frame->width, frame->height, 1);
443  } else if (st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) {
444  size = frame->nb_samples * av_get_bytes_per_sample(frame->format) *
445  frame->channels;
446  if ((ret = av_new_packet(pkt, size)) < 0)
447  goto fail;
448  memcpy(pkt->data, frame->data[0], size);
449  }
450 
451  frame_metadata = frame->metadata;
452  if (frame_metadata) {
453  size_t size;
454  uint8_t *metadata = av_packet_pack_dictionary(frame_metadata, &size);
455 
456  if (!metadata) {
457  ret = AVERROR(ENOMEM);
458  goto fail;
459  }
461  metadata, size)) < 0) {
462  av_freep(&metadata);
463  goto fail;
464  }
465  }
466 
467  if ((ret = create_subcc_packet(avctx, frame, min_pts_sink_idx)) < 0) {
468  goto fail;
469  }
470 
471  pkt->stream_index = stream_idx;
472  pkt->pts = frame->pts;
473  pkt->pos = frame->pkt_pos;
475  return size;
476 fail:
478  return ret;
479 
480 }
481 
482 #define OFFSET(x) offsetof(LavfiContext, x)
483 
484 #define DEC AV_OPT_FLAG_DECODING_PARAM
485 
486 static const AVOption options[] = {
487  { "graph", "set libavfilter graph", OFFSET(graph_str), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
488  { "graph_file","set libavfilter graph filename", OFFSET(graph_filename), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC},
489  { "dumpgraph", "dump graph to stderr", OFFSET(dump_graph), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
490  { NULL },
491 };
492 
493 static const AVClass lavfi_class = {
494  .class_name = "lavfi indev",
495  .item_name = av_default_item_name,
496  .option = options,
497  .version = LIBAVUTIL_VERSION_INT,
498  .category = AV_CLASS_CATEGORY_DEVICE_INPUT,
499 };
500 
502  .name = "lavfi",
503  .long_name = NULL_IF_CONFIG_SMALL("Libavfilter virtual input device"),
504  .priv_data_size = sizeof(LavfiContext),
508  .flags = AVFMT_NOFILE,
509  .priv_class = &lavfi_class,
510 };
AV_CODEC_ID_EIA_608
@ AV_CODEC_ID_EIA_608
Definition: codec_id.h:531
AVMEDIA_TYPE_SUBTITLE
@ AVMEDIA_TYPE_SUBTITLE
Definition: avutil.h:204
AV_BPRINT_SIZE_UNLIMITED
#define AV_BPRINT_SIZE_UNLIMITED
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:123
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: utils.c:724
LavfiContext::stream_sink_map
int * stream_sink_map
Definition: lavfi.c:55
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
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:234
av_bprint_init
void av_bprint_init(AVBPrint *buf, unsigned size_init, unsigned size_max)
Definition: bprint.c:68
av_frame_get_side_data
AVFrameSideData * av_frame_get_side_data(const AVFrame *frame, enum AVFrameSideDataType type)
Definition: frame.c:617
sample_fmts
static enum AVSampleFormat sample_fmts[]
Definition: adpcmenc.c:948
av_pix_fmt_desc_get
const AVPixFmtDescriptor * av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
Definition: pixdesc.c:2564
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
LavfiContext::nb_sinks
int nb_sinks
Definition: lavfi.c:58
AV_FRAME_DATA_A53_CC
@ AV_FRAME_DATA_A53_CC
ATSC A53 Part 4 Closed Captions.
Definition: frame.h:58
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:140
create_subcc_packet
static int create_subcc_packet(AVFormatContext *avctx, AVFrame *frame, int sink_idx)
Definition: lavfi.c:364
AV_TIME_BASE_Q
#define AV_TIME_BASE_Q
Internal time base represented as fractional value.
Definition: avutil.h:260
av_opt_set_int_list
#define av_opt_set_int_list(obj, name, val, term, flags)
Set a binary option to an integer list.
Definition: opt.h:713
AV_CODEC_ID_RAWVIDEO
@ AV_CODEC_ID_RAWVIDEO
Definition: codec_id.h:63
av_frame_free
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:112
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:303
pixdesc.h
AVFormatContext::streams
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1165
AVPacket::data
uint8_t * data
Definition: packet.h:373
AVOption
AVOption.
Definition: opt.h:247
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:1252
AVFilter::name
const char * name
Filter name.
Definition: avfilter.h:153
lavfi_read_packet
static int lavfi_read_packet(AVFormatContext *avctx, AVPacket *pkt)
Definition: lavfi.c:384
av_malloc
#define av_malloc(s)
Definition: tableprint_vlc.h:31
avfilter_graph_free
void avfilter_graph_free(AVFilterGraph **graph)
Free a graph, destroy its links, and set *graph to NULL.
Definition: avfiltergraph.c:121
AV_PIX_FMT_NB
@ AV_PIX_FMT_NB
number of pixel formats, DO NOT USE THIS if you want to link with shared libav* because the number of...
Definition: pixfmt.h:355
AVFormatContext::interrupt_callback
AVIOInterruptCB interrupt_callback
Custom interrupt callbacks for the I/O layer.
Definition: avformat.h:1364
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:140
AVCodecParameters::channels
int channels
Audio only.
Definition: codec_par.h:166
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:1181
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:191
LavfiContext::graph_filename
char * graph_filename
Definition: lavfi.c:49
fail
#define fail()
Definition: checkasm.h:127
avfilter_graph_alloc
AVFilterGraph * avfilter_graph_alloc(void)
Allocate a filter graph.
Definition: avfiltergraph.c:84
AV_PIX_FMT_FLAG_HWACCEL
#define AV_PIX_FMT_FLAG_HWACCEL
Pixel format is an HW accelerated format.
Definition: pixdesc.h:128
read_close
static av_cold int read_close(AVFormatContext *ctx)
Definition: libcdio.c:141
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:99
AV_PKT_DATA_STRINGS_METADATA
@ AV_PKT_DATA_STRINGS_METADATA
A list of zero terminated key/value strings.
Definition: packet.h:172
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:212
AVInputFormat
Definition: avformat.h:626
av_cold
#define av_cold
Definition: attributes.h:90
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:89
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:99
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:1271
AVCodecParameters::sample_aspect_ratio
AVRational sample_aspect_ratio
Video only.
Definition: codec_par.h:136
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:631
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
AVCodecParameters::width
int width
Video only.
Definition: codec_par.h:126
lavfi_class
static const AVClass lavfi_class
Definition: lavfi.c:493
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)
pix_fmts
static enum AVPixelFormat pix_fmts[]
Definition: libkvazaar.c:290
options
static const AVOption options[]
Definition: lavfi.c:486
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:49
AVFormatContext
Format I/O context.
Definition: avformat.h:1097
avfilter_get_by_name
const AVFilter * avfilter_get_by_name(const char *name)
Get a filter definition matching the given name.
Definition: allfilters.c:557
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:992
LIBAVUTIL_VERSION_INT
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:527
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:1160
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:868
NULL
#define NULL
Definition: coverity.c:32
DEC
#define DEC
Definition: lavfi.c:484
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:1634
av_default_item_name
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:235
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:805
av_buffersink_get_channel_layout
uint64_t av_buffersink_get_channel_layout(const AVFilterContext *ctx)
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:474
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:170
av_opt_set_int
int av_opt_set_int(void *obj, const char *name, int64_t val, int search_flags)
Definition: opt.c:589
av_bprint_is_complete
static int av_bprint_is_complete(const AVBPrint *buf)
Test if the print buffer is complete (not truncated).
Definition: bprint.h:185
for
for(j=16;j >0;--j)
Definition: h264pred_template.c:469
ff_lavfi_demuxer
const AVInputFormat ff_lavfi_demuxer
Definition: lavfi.c:501
AVFormatContext::nb_streams
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition: avformat.h:1153
ff_dlog
#define ff_dlog(a,...)
Definition: tableprint_vlc.h:29
AVIOContext
Bytestream IO Context.
Definition: avio.h:161
OFFSET
#define OFFSET(x)
Definition: lavfi.c:482
AVMediaType
AVMediaType
Definition: avutil.h:199
AVPacket::size
int size
Definition: packet.h:374
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
av_get_padded_bits_per_pixel
int av_get_padded_bits_per_pixel(const AVPixFmtDescriptor *pixdesc)
Return the number of bits per pixel for the pixel format described by pixdesc, including any padding ...
Definition: pixdesc.c:2529
avfilter_link
int avfilter_link(AVFilterContext *src, unsigned srcpad, AVFilterContext *dst, unsigned dstpad)
Link two filters together.
Definition: avfilter.c:162
AVFormatContext::url
char * url
input or output URL.
Definition: avformat.h:1180
AV_SAMPLE_FMT_NONE
@ AV_SAMPLE_FMT_NONE
Definition: samplefmt.h:59
size
int size
Definition: twinvq_data.h:10344
AVFrameSideData::data
uint8_t * data
Definition: frame.h:211
AVFMT_NOFILE
#define AVFMT_NOFILE
Demuxer will use avio_open, no opened file should be provided by the caller.
Definition: avformat.h:463
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:901
avdevice.h
AV_OPT_SEARCH_CHILDREN
#define AV_OPT_SEARCH_CHILDREN
Search in possible children of the given object first.
Definition: opt.h:559
LavfiContext::sink_stream_subcc_map
int * sink_stream_subcc_map
Definition: lavfi.c:56
av_image_get_buffer_size
int av_image_get_buffer_size(enum AVPixelFormat pix_fmt, int width, int height, int align)
Return the size in bytes of the amount of data required to store an image with the given parameters.
Definition: imgutils.c:466
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:302
av_buffersink_get_type
enum AVMediaType av_buffersink_get_type(const AVFilterContext *ctx)
buffersink.h
LavfiContext::subcc_packet
AVPacket subcc_packet
Definition: lavfi.c:59
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:1213
create_subcc_streams
static int create_subcc_streams(AVFormatContext *avctx)
Definition: lavfi.c:98
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:271
AVPacket::pts
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:366
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:106
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:60
AVCodecParameters::height
int height
Definition: codec_par.h:127
av_malloc_array
#define av_malloc_array(a, b)
Definition: tableprint_vlc.h:32
AVSampleFormat
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:58
av_frame_unref
void av_frame_unref(AVFrame *frame)
Unreference all the buffers referenced by frame and reset the frame fields.
Definition: frame.c:437
AV_SAMPLE_FMT_S16
@ AV_SAMPLE_FMT_S16
signed 16 bits
Definition: samplefmt.h:61
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:263
av_buffersink_get_h
int av_buffersink_get_h(const AVFilterContext *ctx)
AVFilter
Filter definition.
Definition: avfilter.h:149
AVStream::id
int id
Format-specific stream ID.
Definition: avformat.h:852
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:845
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:155
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:978
suffix
const char * suffix
Definition: checkasm.c:200
lavfi_read_close
static av_cold int lavfi_read_close(AVFormatContext *avctx)
Definition: lavfi.c:83
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
AV_PIX_FMT_NONE
@ AV_PIX_FMT_NONE
Definition: pixfmt.h:65
avfilter.h
av_buffersink_get_channels
int av_buffersink_get_channels(const AVFilterContext *ctx)
create_all_formats
static int * create_all_formats(int n)
Definition: lavfi.c:62
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: utils.c:1146
file.h
AVPacket::stream_index
int stream_index
Definition: packet.h:375
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:346
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:562
AVIO_FLAG_READ
#define AVIO_FLAG_READ
read-only
Definition: avio.h:603
av_strdup
char * av_strdup(const char *s)
Duplicate a string.
Definition: mem.c:279
desc
const char * desc
Definition: libsvtav1.c:79
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
mem.h
AVFrameSideData
Structure to hold side data for an AVFrame.
Definition: frame.h:209
AVCodecParameters::format
int format
Definition: codec_par.h:84
AVPixFmtDescriptor
Descriptor that unambiguously describes how the bits of a pixel are stored in the up to 4 data planes...
Definition: pixdesc.h:69
av_free
#define av_free(p)
Definition: tableprint_vlc.h:34
av_image_copy_to_buffer
int av_image_copy_to_buffer(uint8_t *dst, int dst_size, const uint8_t *const src_data[4], const int src_linesize[4], enum AVPixelFormat pix_fmt, int width, int height, int align)
Copy image data from an image into a buffer.
Definition: imgutils.c:501
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:60
AVPacket
This structure stores compressed data.
Definition: packet.h:350
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:35
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:393
AVCodecParameters::channel_layout
uint64_t channel_layout
Audio only.
Definition: codec_par.h:162
d
d
Definition: ffmpeg_filter.c:156
imgutils.h
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
AV_SAMPLE_FMT_DBL
@ AV_SAMPLE_FMT_DBL
double
Definition: samplefmt.h:64
AV_OPT_TYPE_STRING
@ AV_OPT_TYPE_STRING
Definition: opt.h:228
AV_SAMPLE_FMT_S32
@ AV_SAMPLE_FMT_S32
signed 32 bits
Definition: samplefmt.h:62
AVFilterInOut
A linked-list of the inputs/outputs of the filter chain.
Definition: avfilter.h:965
AVFormatContext::priv_data
void * priv_data
Format private data.
Definition: avformat.h:1125
AV_SAMPLE_FMT_FLT
@ AV_SAMPLE_FMT_FLT
float
Definition: samplefmt.h:63
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:133
av_bprint_chars
void av_bprint_chars(AVBPrint *buf, char c, unsigned n)
Append char c n times to a print buffer.
Definition: bprint.c:139
LavfiContext::decoded_frame
AVFrame * decoded_frame
Definition: lavfi.c:57