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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/log.h"
34 #include "libavutil/mem.h"
35 #include "libavutil/opt.h"
36 #include "libavutil/parseutils.h"
37 #include "libavutil/pixdesc.h"
38 #include "libavfilter/avfilter.h"
40 #include "libavfilter/buffersink.h"
41 #include "libavformat/internal.h"
42 #include "avdevice.h"
43 
44 typedef struct {
45  AVClass *class; ///< class for private options
46  char *graph_str;
48  char *dump_graph;
52  int *sink_eof;
55 } LavfiContext;
56 
57 static int *create_all_formats(int n)
58 {
59  int i, j, *fmts, count = 0;
60 
61  for (i = 0; i < n; i++) {
62  const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(i);
63  if (!(desc->flags & AV_PIX_FMT_FLAG_HWACCEL))
64  count++;
65  }
66 
67  if (!(fmts = av_malloc((count+1) * sizeof(int))))
68  return NULL;
69  for (j = 0, i = 0; i < n; i++) {
70  const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(i);
71  if (!(desc->flags & AV_PIX_FMT_FLAG_HWACCEL))
72  fmts[j++] = i;
73  }
74  fmts[j] = -1;
75  return fmts;
76 }
77 
79 {
80  LavfiContext *lavfi = avctx->priv_data;
81 
82  av_freep(&lavfi->sink_stream_map);
83  av_freep(&lavfi->sink_eof);
84  av_freep(&lavfi->stream_sink_map);
85  av_freep(&lavfi->sinks);
86  avfilter_graph_free(&lavfi->graph);
88 
89  return 0;
90 }
91 
93 {
94  LavfiContext *lavfi = avctx->priv_data;
95  AVFilterInOut *input_links = NULL, *output_links = NULL, *inout;
96  AVFilter *buffersink, *abuffersink;
97  int *pix_fmts = create_all_formats(AV_PIX_FMT_NB);
98  enum AVMediaType type;
99  int ret = 0, i, n;
100 
101 #define FAIL(ERR) { ret = ERR; goto end; }
102 
103  if (!pix_fmts)
104  FAIL(AVERROR(ENOMEM));
105 
107 
108  buffersink = avfilter_get_by_name("buffersink");
109  abuffersink = avfilter_get_by_name("abuffersink");
110 
111  if (lavfi->graph_filename && lavfi->graph_str) {
112  av_log(avctx, AV_LOG_ERROR,
113  "Only one of the graph or graph_file options must be specified\n");
114  FAIL(AVERROR(EINVAL));
115  }
116 
117  if (lavfi->graph_filename) {
118  AVBPrint graph_file_pb;
119  AVIOContext *avio = NULL;
120  ret = avio_open(&avio, lavfi->graph_filename, AVIO_FLAG_READ);
121  if (ret < 0)
122  FAIL(ret);
123  av_bprint_init(&graph_file_pb, 0, AV_BPRINT_SIZE_UNLIMITED);
124  ret = avio_read_to_bprint(avio, &graph_file_pb, INT_MAX);
125  avio_close(avio);
126  av_bprint_chars(&graph_file_pb, '\0', 1);
127  if (!ret && !av_bprint_is_complete(&graph_file_pb))
128  ret = AVERROR(ENOMEM);
129  if (ret) {
130  av_bprint_finalize(&graph_file_pb, NULL);
131  FAIL(ret);
132  }
133  if ((ret = av_bprint_finalize(&graph_file_pb, &lavfi->graph_str)))
134  FAIL(ret);
135  }
136 
137  if (!lavfi->graph_str)
138  lavfi->graph_str = av_strdup(avctx->filename);
139 
140  /* parse the graph, create a stream for each open output */
141  if (!(lavfi->graph = avfilter_graph_alloc()))
142  FAIL(AVERROR(ENOMEM));
143 
144  if ((ret = avfilter_graph_parse_ptr(lavfi->graph, lavfi->graph_str,
145  &input_links, &output_links, avctx)) < 0)
146  FAIL(ret);
147 
148  if (input_links) {
149  av_log(avctx, AV_LOG_ERROR,
150  "Open inputs in the filtergraph are not acceptable\n");
151  FAIL(AVERROR(EINVAL));
152  }
153 
154  /* count the outputs */
155  for (n = 0, inout = output_links; inout; n++, inout = inout->next);
156 
157  if (!(lavfi->sink_stream_map = av_malloc(sizeof(int) * n)))
158  FAIL(AVERROR(ENOMEM));
159  if (!(lavfi->sink_eof = av_mallocz(sizeof(int) * n)))
160  FAIL(AVERROR(ENOMEM));
161  if (!(lavfi->stream_sink_map = av_malloc(sizeof(int) * n)))
162  FAIL(AVERROR(ENOMEM));
163 
164  for (i = 0; i < n; i++)
165  lavfi->stream_sink_map[i] = -1;
166 
167  /* parse the output link names - they need to be of the form out0, out1, ...
168  * create a mapping between them and the streams */
169  for (i = 0, inout = output_links; inout; i++, inout = inout->next) {
170  int stream_idx;
171  if (!strcmp(inout->name, "out"))
172  stream_idx = 0;
173  else if (sscanf(inout->name, "out%d\n", &stream_idx) != 1) {
174  av_log(avctx, AV_LOG_ERROR,
175  "Invalid outpad name '%s'\n", inout->name);
176  FAIL(AVERROR(EINVAL));
177  }
178 
179  if ((unsigned)stream_idx >= n) {
180  av_log(avctx, AV_LOG_ERROR,
181  "Invalid index was specified in output '%s', "
182  "must be a non-negative value < %d\n",
183  inout->name, n);
184  FAIL(AVERROR(EINVAL));
185  }
186 
187  if (lavfi->stream_sink_map[stream_idx] != -1) {
188  av_log(avctx, AV_LOG_ERROR,
189  "An output with stream index %d was already specified\n",
190  stream_idx);
191  FAIL(AVERROR(EINVAL));
192  }
193  lavfi->sink_stream_map[i] = stream_idx;
194  lavfi->stream_sink_map[stream_idx] = i;
195  }
196 
197  /* for each open output create a corresponding stream */
198  for (i = 0, inout = output_links; inout; i++, inout = inout->next) {
199  AVStream *st;
200  if (!(st = avformat_new_stream(avctx, NULL)))
201  FAIL(AVERROR(ENOMEM));
202  st->id = i;
203  }
204 
205  /* create a sink for each output and connect them to the graph */
206  lavfi->sinks = av_malloc_array(avctx->nb_streams, sizeof(AVFilterContext *));
207  if (!lavfi->sinks)
208  FAIL(AVERROR(ENOMEM));
209 
210  for (i = 0, inout = output_links; inout; i++, inout = inout->next) {
211  AVFilterContext *sink;
212 
213  type = inout->filter_ctx->output_pads[inout->pad_idx].type;
214 
215  if (type == AVMEDIA_TYPE_VIDEO && ! buffersink ||
216  type == AVMEDIA_TYPE_AUDIO && ! abuffersink) {
217  av_log(avctx, AV_LOG_ERROR, "Missing required buffersink filter, aborting.\n");
219  }
220 
221  if (type == AVMEDIA_TYPE_VIDEO) {
222  ret = avfilter_graph_create_filter(&sink, buffersink,
223  inout->name, NULL,
224  NULL, lavfi->graph);
225  if (ret >= 0)
226  ret = av_opt_set_int_list(sink, "pix_fmts", pix_fmts, AV_PIX_FMT_NONE, AV_OPT_SEARCH_CHILDREN);
227  if (ret < 0)
228  goto end;
229  } else if (type == AVMEDIA_TYPE_AUDIO) {
234  AV_SAMPLE_FMT_DBL, -1 };
235 
236  ret = avfilter_graph_create_filter(&sink, abuffersink,
237  inout->name, NULL,
238  NULL, lavfi->graph);
239  if (ret >= 0)
240  ret = av_opt_set_int_list(sink, "sample_fmts", sample_fmts, AV_SAMPLE_FMT_NONE, AV_OPT_SEARCH_CHILDREN);
241  if (ret < 0)
242  goto end;
243  ret = av_opt_set_int(sink, "all_channel_counts", 1,
245  if (ret < 0)
246  goto end;
247  } else {
248  av_log(avctx, AV_LOG_ERROR,
249  "Output '%s' is not a video or audio output, not yet supported\n", inout->name);
250  FAIL(AVERROR(EINVAL));
251  }
252 
253  lavfi->sinks[i] = sink;
254  if ((ret = avfilter_link(inout->filter_ctx, inout->pad_idx, sink, 0)) < 0)
255  FAIL(ret);
256  }
257 
258  /* configure the graph */
259  if ((ret = avfilter_graph_config(lavfi->graph, avctx)) < 0)
260  FAIL(ret);
261 
262  if (lavfi->dump_graph) {
263  char *dump = avfilter_graph_dump(lavfi->graph, lavfi->dump_graph);
264  fputs(dump, stderr);
265  fflush(stderr);
266  av_free(dump);
267  }
268 
269  /* fill each stream with the information in the corresponding sink */
270  for (i = 0; i < avctx->nb_streams; i++) {
271  AVFilterLink *link = lavfi->sinks[lavfi->stream_sink_map[i]]->inputs[0];
272  AVStream *st = avctx->streams[i];
273  st->codec->codec_type = link->type;
274  avpriv_set_pts_info(st, 64, link->time_base.num, link->time_base.den);
275  if (link->type == AVMEDIA_TYPE_VIDEO) {
277  st->codec->pix_fmt = link->format;
278  st->codec->time_base = link->time_base;
279  st->codec->width = link->w;
280  st->codec->height = link->h;
281  st ->sample_aspect_ratio =
283  avctx->probesize = FFMAX(avctx->probesize,
284  link->w * link->h *
286  30);
287  } else if (link->type == AVMEDIA_TYPE_AUDIO) {
288  st->codec->codec_id = av_get_pcm_codec(link->format, -1);
290  st->codec->sample_fmt = link->format;
291  st->codec->sample_rate = link->sample_rate;
292  st->codec->time_base = link->time_base;
293  st->codec->channel_layout = link->channel_layout;
294  if (st->codec->codec_id == AV_CODEC_ID_NONE)
295  av_log(avctx, AV_LOG_ERROR,
296  "Could not find PCM codec for sample format %s.\n",
298  }
299  }
300 
301  if (!(lavfi->decoded_frame = av_frame_alloc()))
302  FAIL(AVERROR(ENOMEM));
303 
304 end:
305  av_free(pix_fmts);
306  avfilter_inout_free(&input_links);
307  avfilter_inout_free(&output_links);
308  if (ret < 0)
309  lavfi_read_close(avctx);
310  return ret;
311 }
312 
314 {
315  LavfiContext *lavfi = avctx->priv_data;
316  double min_pts = DBL_MAX;
317  int stream_idx, min_pts_sink_idx = 0;
318  AVFrame *frame = lavfi->decoded_frame;
319  AVPicture pict;
320  AVDictionary *frame_metadata;
321  int ret, i;
322  int size = 0;
323 
324  /* iterate through all the graph sinks. Select the sink with the
325  * minimum PTS */
326  for (i = 0; i < avctx->nb_streams; i++) {
327  AVRational tb = lavfi->sinks[i]->inputs[0]->time_base;
328  double d;
329  int ret;
330 
331  if (lavfi->sink_eof[i])
332  continue;
333 
334  ret = av_buffersink_get_frame_flags(lavfi->sinks[i], frame,
336  if (ret == AVERROR_EOF) {
337  av_dlog(avctx, "EOF sink_idx:%d\n", i);
338  lavfi->sink_eof[i] = 1;
339  continue;
340  } else if (ret < 0)
341  return ret;
342  d = av_rescale_q(frame->pts, tb, AV_TIME_BASE_Q);
343  av_dlog(avctx, "sink_idx:%d time:%f\n", i, d);
344  av_frame_unref(frame);
345 
346  if (d < min_pts) {
347  min_pts = d;
348  min_pts_sink_idx = i;
349  }
350  }
351  if (min_pts == DBL_MAX)
352  return AVERROR_EOF;
353 
354  av_dlog(avctx, "min_pts_sink_idx:%i\n", min_pts_sink_idx);
355 
356  av_buffersink_get_frame_flags(lavfi->sinks[min_pts_sink_idx], frame, 0);
357  stream_idx = lavfi->sink_stream_map[min_pts_sink_idx];
358 
359  if (frame->width /* FIXME best way of testing a video */) {
360  size = avpicture_get_size(frame->format, frame->width, frame->height);
361  if ((ret = av_new_packet(pkt, size)) < 0)
362  return ret;
363 
364  memcpy(pict.data, frame->data, 4*sizeof(frame->data[0]));
365  memcpy(pict.linesize, frame->linesize, 4*sizeof(frame->linesize[0]));
366 
367  avpicture_layout(&pict, frame->format, frame->width, frame->height,
368  pkt->data, size);
369  } else if (av_frame_get_channels(frame) /* FIXME test audio */) {
370  size = frame->nb_samples * av_get_bytes_per_sample(frame->format) *
371  av_frame_get_channels(frame);
372  if ((ret = av_new_packet(pkt, size)) < 0)
373  return ret;
374  memcpy(pkt->data, frame->data[0], size);
375  }
376 
377  frame_metadata = av_frame_get_metadata(frame);
378  if (frame_metadata) {
379  uint8_t *metadata;
380  AVDictionaryEntry *e = NULL;
381  AVBPrint meta_buf;
382 
384  while ((e = av_dict_get(frame_metadata, "", e, AV_DICT_IGNORE_SUFFIX))) {
385  av_bprintf(&meta_buf, "%s", e->key);
386  av_bprint_chars(&meta_buf, '\0', 1);
387  av_bprintf(&meta_buf, "%s", e->value);
388  av_bprint_chars(&meta_buf, '\0', 1);
389  }
390  if (!av_bprint_is_complete(&meta_buf) ||
392  meta_buf.len))) {
393  av_bprint_finalize(&meta_buf, NULL);
394  return AVERROR(ENOMEM);
395  }
396  memcpy(metadata, meta_buf.str, meta_buf.len);
397  av_bprint_finalize(&meta_buf, NULL);
398  }
399 
400  pkt->stream_index = stream_idx;
401  pkt->pts = frame->pts;
402  pkt->pos = av_frame_get_pkt_pos(frame);
403  pkt->size = size;
404  av_frame_unref(frame);
405  return size;
406 }
407 
408 #define OFFSET(x) offsetof(LavfiContext, x)
409 
410 #define DEC AV_OPT_FLAG_DECODING_PARAM
411 
412 static const AVOption options[] = {
413  { "graph", "set libavfilter graph", OFFSET(graph_str), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
414  { "graph_file","set libavfilter graph filename", OFFSET(graph_filename), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC},
415  { "dumpgraph", "dump graph to stderr", OFFSET(dump_graph), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
416  { NULL },
417 };
418 
419 static const AVClass lavfi_class = {
420  .class_name = "lavfi indev",
421  .item_name = av_default_item_name,
422  .option = options,
423  .version = LIBAVUTIL_VERSION_INT,
424  .category = AV_CLASS_CATEGORY_DEVICE_INPUT,
425 };
426 
428  .name = "lavfi",
429  .long_name = NULL_IF_CONFIG_SMALL("Libavfilter virtual input device"),
430  .priv_data_size = sizeof(LavfiContext),
434  .flags = AVFMT_NOFILE,
435  .priv_class = &lavfi_class,
436 };