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v4l2.c
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1 /*
2  * Copyright (c) 2000,2001 Fabrice Bellard
3  * Copyright (c) 2006 Luca Abeni
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * Video4Linux2 grab interface
25  *
26  * Part of this file is based on the V4L2 video capture example
27  * (http://linuxtv.org/downloads/v4l-dvb-apis/capture-example.html)
28  *
29  * Thanks to Michael Niedermayer for providing the mapping between
30  * V4L2_PIX_FMT_* and AV_PIX_FMT_*
31  */
32 
33 #include <stdatomic.h>
34 
35 #include "v4l2-common.h"
36 #include <dirent.h>
37 
38 #if CONFIG_LIBV4L2
39 #include <libv4l2.h>
40 #endif
41 
42 static const int desired_video_buffers = 256;
43 
44 #define V4L_ALLFORMATS 3
45 #define V4L_RAWFORMATS 1
46 #define V4L_COMPFORMATS 2
47 
48 /**
49  * Return timestamps to the user exactly as returned by the kernel
50  */
51 #define V4L_TS_DEFAULT 0
52 /**
53  * Autodetect the kind of timestamps returned by the kernel and convert to
54  * absolute (wall clock) timestamps.
55  */
56 #define V4L_TS_ABS 1
57 /**
58  * Assume kernel timestamps are from the monotonic clock and convert to
59  * absolute timestamps.
60  */
61 #define V4L_TS_MONO2ABS 2
62 
63 /**
64  * Once the kind of timestamps returned by the kernel have been detected,
65  * the value of the timefilter (NULL or not) determines whether a conversion
66  * takes place.
67  */
68 #define V4L_TS_CONVERT_READY V4L_TS_DEFAULT
69 
70 struct video_data {
71  AVClass *class;
72  int fd;
73  int pixelformat; /* V4L2_PIX_FMT_* */
74  int width, height;
78  int ts_mode;
80  int64_t last_time_m;
81 
82  int buffers;
84  void **buf_start;
85  unsigned int *buf_len;
86  char *standard;
87  v4l2_std_id std_id;
88  int channel;
89  char *pixel_format; /**< Set by a private option. */
90  int list_format; /**< Set by a private option. */
91  int list_standard; /**< Set by a private option. */
92  char *framerate; /**< Set by a private option. */
93 
95  int (*open_f)(const char *file, int oflag, ...);
96  int (*close_f)(int fd);
97  int (*dup_f)(int fd);
98  int (*ioctl_f)(int fd, unsigned long int request, ...);
99  ssize_t (*read_f)(int fd, void *buffer, size_t n);
100  void *(*mmap_f)(void *start, size_t length, int prot, int flags, int fd, int64_t offset);
101  int (*munmap_f)(void *_start, size_t length);
102 };
103 
104 struct buff_data {
105  struct video_data *s;
106  int index;
107 };
108 
109 static int device_open(AVFormatContext *ctx, const char* device_path)
110 {
111  struct video_data *s = ctx->priv_data;
112  struct v4l2_capability cap;
113  int fd;
114  int err;
115  int flags = O_RDWR;
116 
117 #define SET_WRAPPERS(prefix) do { \
118  s->open_f = prefix ## open; \
119  s->close_f = prefix ## close; \
120  s->dup_f = prefix ## dup; \
121  s->ioctl_f = prefix ## ioctl; \
122  s->read_f = prefix ## read; \
123  s->mmap_f = prefix ## mmap; \
124  s->munmap_f = prefix ## munmap; \
125 } while (0)
126 
127  if (s->use_libv4l2) {
128 #if CONFIG_LIBV4L2
129  SET_WRAPPERS(v4l2_);
130 #else
131  av_log(ctx, AV_LOG_ERROR, "libavdevice is not built with libv4l2 support.\n");
132  return AVERROR(EINVAL);
133 #endif
134  } else {
135  SET_WRAPPERS();
136  }
137 
138 #define v4l2_open s->open_f
139 #define v4l2_close s->close_f
140 #define v4l2_dup s->dup_f
141 #define v4l2_ioctl s->ioctl_f
142 #define v4l2_read s->read_f
143 #define v4l2_mmap s->mmap_f
144 #define v4l2_munmap s->munmap_f
145 
146  if (ctx->flags & AVFMT_FLAG_NONBLOCK) {
147  flags |= O_NONBLOCK;
148  }
149 
150  fd = v4l2_open(device_path, flags, 0);
151  if (fd < 0) {
152  err = AVERROR(errno);
153  av_log(ctx, AV_LOG_ERROR, "Cannot open video device %s: %s\n",
154  device_path, av_err2str(err));
155  return err;
156  }
157 
158  if (v4l2_ioctl(fd, VIDIOC_QUERYCAP, &cap) < 0) {
159  err = AVERROR(errno);
160  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYCAP): %s\n",
161  av_err2str(err));
162  goto fail;
163  }
164 
165  av_log(ctx, AV_LOG_VERBOSE, "fd:%d capabilities:%x\n",
166  fd, cap.capabilities);
167 
168  if (!(cap.capabilities & V4L2_CAP_VIDEO_CAPTURE)) {
169  av_log(ctx, AV_LOG_ERROR, "Not a video capture device.\n");
170  err = AVERROR(ENODEV);
171  goto fail;
172  }
173 
174  if (!(cap.capabilities & V4L2_CAP_STREAMING)) {
175  av_log(ctx, AV_LOG_ERROR,
176  "The device does not support the streaming I/O method.\n");
177  err = AVERROR(ENOSYS);
178  goto fail;
179  }
180 
181  return fd;
182 
183 fail:
184  v4l2_close(fd);
185  return err;
186 }
187 
188 static int device_init(AVFormatContext *ctx, int *width, int *height,
189  uint32_t pixelformat)
190 {
191  struct video_data *s = ctx->priv_data;
192  struct v4l2_format fmt = { .type = V4L2_BUF_TYPE_VIDEO_CAPTURE };
193  int res = 0;
194 
195  fmt.fmt.pix.width = *width;
196  fmt.fmt.pix.height = *height;
197  fmt.fmt.pix.pixelformat = pixelformat;
198  fmt.fmt.pix.field = V4L2_FIELD_ANY;
199 
200  /* Some drivers will fail and return EINVAL when the pixelformat
201  is not supported (even if type field is valid and supported) */
202  if (v4l2_ioctl(s->fd, VIDIOC_S_FMT, &fmt) < 0)
203  res = AVERROR(errno);
204 
205  if ((*width != fmt.fmt.pix.width) || (*height != fmt.fmt.pix.height)) {
206  av_log(ctx, AV_LOG_INFO,
207  "The V4L2 driver changed the video from %dx%d to %dx%d\n",
208  *width, *height, fmt.fmt.pix.width, fmt.fmt.pix.height);
209  *width = fmt.fmt.pix.width;
210  *height = fmt.fmt.pix.height;
211  }
212 
213  if (pixelformat != fmt.fmt.pix.pixelformat) {
214  av_log(ctx, AV_LOG_DEBUG,
215  "The V4L2 driver changed the pixel format "
216  "from 0x%08X to 0x%08X\n",
217  pixelformat, fmt.fmt.pix.pixelformat);
218  res = AVERROR(EINVAL);
219  }
220 
221  if (fmt.fmt.pix.field == V4L2_FIELD_INTERLACED) {
222  av_log(ctx, AV_LOG_DEBUG,
223  "The V4L2 driver is using the interlaced mode\n");
224  s->interlaced = 1;
225  }
226 
227  return res;
228 }
229 
230 static int first_field(const struct video_data *s)
231 {
232  int res;
233  v4l2_std_id std;
234 
235  res = v4l2_ioctl(s->fd, VIDIOC_G_STD, &std);
236  if (res < 0)
237  return 0;
238  if (std & V4L2_STD_NTSC)
239  return 0;
240 
241  return 1;
242 }
243 
244 #if HAVE_STRUCT_V4L2_FRMIVALENUM_DISCRETE
245 static void list_framesizes(AVFormatContext *ctx, uint32_t pixelformat)
246 {
247  const struct video_data *s = ctx->priv_data;
248  struct v4l2_frmsizeenum vfse = { .pixel_format = pixelformat };
249 
250  while(!v4l2_ioctl(s->fd, VIDIOC_ENUM_FRAMESIZES, &vfse)) {
251  switch (vfse.type) {
252  case V4L2_FRMSIZE_TYPE_DISCRETE:
253  av_log(ctx, AV_LOG_INFO, " %ux%u",
254  vfse.discrete.width, vfse.discrete.height);
255  break;
256  case V4L2_FRMSIZE_TYPE_CONTINUOUS:
257  case V4L2_FRMSIZE_TYPE_STEPWISE:
258  av_log(ctx, AV_LOG_INFO, " {%u-%u, %u}x{%u-%u, %u}",
259  vfse.stepwise.min_width,
260  vfse.stepwise.max_width,
261  vfse.stepwise.step_width,
262  vfse.stepwise.min_height,
263  vfse.stepwise.max_height,
264  vfse.stepwise.step_height);
265  }
266  vfse.index++;
267  }
268 }
269 #endif
270 
271 static void list_formats(AVFormatContext *ctx, int type)
272 {
273  const struct video_data *s = ctx->priv_data;
274  struct v4l2_fmtdesc vfd = { .type = V4L2_BUF_TYPE_VIDEO_CAPTURE };
275 
276  while(!v4l2_ioctl(s->fd, VIDIOC_ENUM_FMT, &vfd)) {
277  enum AVCodecID codec_id = ff_fmt_v4l2codec(vfd.pixelformat);
278  enum AVPixelFormat pix_fmt = ff_fmt_v4l2ff(vfd.pixelformat, codec_id);
279 
280  vfd.index++;
281 
282  if (!(vfd.flags & V4L2_FMT_FLAG_COMPRESSED) &&
283  type & V4L_RAWFORMATS) {
284  const char *fmt_name = av_get_pix_fmt_name(pix_fmt);
285  av_log(ctx, AV_LOG_INFO, "Raw : %11s : %20s :",
286  fmt_name ? fmt_name : "Unsupported",
287  vfd.description);
288  } else if (vfd.flags & V4L2_FMT_FLAG_COMPRESSED &&
289  type & V4L_COMPFORMATS) {
290  const AVCodecDescriptor *desc = avcodec_descriptor_get(codec_id);
291  av_log(ctx, AV_LOG_INFO, "Compressed: %11s : %20s :",
292  desc ? desc->name : "Unsupported",
293  vfd.description);
294  } else {
295  continue;
296  }
297 
298 #ifdef V4L2_FMT_FLAG_EMULATED
299  if (vfd.flags & V4L2_FMT_FLAG_EMULATED)
300  av_log(ctx, AV_LOG_INFO, " Emulated :");
301 #endif
302 #if HAVE_STRUCT_V4L2_FRMIVALENUM_DISCRETE
303  list_framesizes(ctx, vfd.pixelformat);
304 #endif
305  av_log(ctx, AV_LOG_INFO, "\n");
306  }
307 }
308 
310 {
311  int ret;
312  struct video_data *s = ctx->priv_data;
313  struct v4l2_standard standard;
314 
315  if (s->std_id == 0)
316  return;
317 
318  for (standard.index = 0; ; standard.index++) {
319  if (v4l2_ioctl(s->fd, VIDIOC_ENUMSTD, &standard) < 0) {
320  ret = AVERROR(errno);
321  if (ret == AVERROR(EINVAL)) {
322  break;
323  } else {
324  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_ENUMSTD): %s\n", av_err2str(ret));
325  return;
326  }
327  }
328  av_log(ctx, AV_LOG_INFO, "%2d, %16"PRIx64", %s\n",
329  standard.index, (uint64_t)standard.id, standard.name);
330  }
331 }
332 
333 static int mmap_init(AVFormatContext *ctx)
334 {
335  int i, res;
336  struct video_data *s = ctx->priv_data;
337  struct v4l2_requestbuffers req = {
338  .type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
339  .count = desired_video_buffers,
340  .memory = V4L2_MEMORY_MMAP
341  };
342 
343  if (v4l2_ioctl(s->fd, VIDIOC_REQBUFS, &req) < 0) {
344  res = AVERROR(errno);
345  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_REQBUFS): %s\n", av_err2str(res));
346  return res;
347  }
348 
349  if (req.count < 2) {
350  av_log(ctx, AV_LOG_ERROR, "Insufficient buffer memory\n");
351  return AVERROR(ENOMEM);
352  }
353  s->buffers = req.count;
354  s->buf_start = av_malloc_array(s->buffers, sizeof(void *));
355  if (!s->buf_start) {
356  av_log(ctx, AV_LOG_ERROR, "Cannot allocate buffer pointers\n");
357  return AVERROR(ENOMEM);
358  }
359  s->buf_len = av_malloc_array(s->buffers, sizeof(unsigned int));
360  if (!s->buf_len) {
361  av_log(ctx, AV_LOG_ERROR, "Cannot allocate buffer sizes\n");
362  av_freep(&s->buf_start);
363  return AVERROR(ENOMEM);
364  }
365 
366  for (i = 0; i < req.count; i++) {
367  struct v4l2_buffer buf = {
368  .type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
369  .index = i,
370  .memory = V4L2_MEMORY_MMAP
371  };
372  if (v4l2_ioctl(s->fd, VIDIOC_QUERYBUF, &buf) < 0) {
373  res = AVERROR(errno);
374  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYBUF): %s\n", av_err2str(res));
375  return res;
376  }
377 
378  s->buf_len[i] = buf.length;
379  if (s->frame_size > 0 && s->buf_len[i] < s->frame_size) {
380  av_log(ctx, AV_LOG_ERROR,
381  "buf_len[%d] = %d < expected frame size %d\n",
382  i, s->buf_len[i], s->frame_size);
383  return AVERROR(ENOMEM);
384  }
385  s->buf_start[i] = v4l2_mmap(NULL, buf.length,
386  PROT_READ | PROT_WRITE, MAP_SHARED,
387  s->fd, buf.m.offset);
388 
389  if (s->buf_start[i] == MAP_FAILED) {
390  res = AVERROR(errno);
391  av_log(ctx, AV_LOG_ERROR, "mmap: %s\n", av_err2str(res));
392  return res;
393  }
394  }
395 
396  return 0;
397 }
398 
399 static int enqueue_buffer(struct video_data *s, struct v4l2_buffer *buf)
400 {
401  int res = 0;
402 
403  if (v4l2_ioctl(s->fd, VIDIOC_QBUF, buf) < 0) {
404  res = AVERROR(errno);
405  av_log(NULL, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF): %s\n", av_err2str(res));
406  } else {
408  }
409 
410  return res;
411 }
412 
413 static void mmap_release_buffer(void *opaque, uint8_t *data)
414 {
415  struct v4l2_buffer buf = { 0 };
416  struct buff_data *buf_descriptor = opaque;
417  struct video_data *s = buf_descriptor->s;
418 
419  buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
420  buf.memory = V4L2_MEMORY_MMAP;
421  buf.index = buf_descriptor->index;
422  av_free(buf_descriptor);
423 
424  enqueue_buffer(s, &buf);
425 }
426 
427 #if HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC)
428 static int64_t av_gettime_monotonic(void)
429 {
430  return av_gettime_relative();
431 }
432 #endif
433 
434 static int init_convert_timestamp(AVFormatContext *ctx, int64_t ts)
435 {
436  struct video_data *s = ctx->priv_data;
437  int64_t now;
438 
439  now = av_gettime();
440  if (s->ts_mode == V4L_TS_ABS &&
441  ts <= now + 1 * AV_TIME_BASE && ts >= now - 10 * AV_TIME_BASE) {
442  av_log(ctx, AV_LOG_INFO, "Detected absolute timestamps\n");
444  return 0;
445  }
446 #if HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC)
447  if (ctx->streams[0]->avg_frame_rate.num) {
448  now = av_gettime_monotonic();
449  if (s->ts_mode == V4L_TS_MONO2ABS ||
450  (ts <= now + 1 * AV_TIME_BASE && ts >= now - 10 * AV_TIME_BASE)) {
451  AVRational tb = {AV_TIME_BASE, 1};
452  int64_t period = av_rescale_q(1, tb, ctx->streams[0]->avg_frame_rate);
453  av_log(ctx, AV_LOG_INFO, "Detected monotonic timestamps, converting\n");
454  /* microseconds instead of seconds, MHz instead of Hz */
455  s->timefilter = ff_timefilter_new(1, period, 1.0E-6);
456  if (!s->timefilter)
457  return AVERROR(ENOMEM);
459  return 0;
460  }
461  }
462 #endif
463  av_log(ctx, AV_LOG_ERROR, "Unknown timestamps\n");
464  return AVERROR(EIO);
465 }
466 
467 static int convert_timestamp(AVFormatContext *ctx, int64_t *ts)
468 {
469  struct video_data *s = ctx->priv_data;
470 
471  if (s->ts_mode) {
472  int r = init_convert_timestamp(ctx, *ts);
473  if (r < 0)
474  return r;
475  }
476 #if HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC)
477  if (s->timefilter) {
478  int64_t nowa = av_gettime();
479  int64_t nowm = av_gettime_monotonic();
480  ff_timefilter_update(s->timefilter, nowa, nowm - s->last_time_m);
481  s->last_time_m = nowm;
482  *ts = ff_timefilter_eval(s->timefilter, *ts - nowm);
483  }
484 #endif
485  return 0;
486 }
487 
489 {
490  struct video_data *s = ctx->priv_data;
491  struct v4l2_buffer buf = {
492  .type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
493  .memory = V4L2_MEMORY_MMAP
494  };
495  struct timeval buf_ts;
496  int res;
497 
498  pkt->size = 0;
499 
500  /* FIXME: Some special treatment might be needed in case of loss of signal... */
501  while ((res = v4l2_ioctl(s->fd, VIDIOC_DQBUF, &buf)) < 0 && (errno == EINTR));
502  if (res < 0) {
503  if (errno == EAGAIN)
504  return AVERROR(EAGAIN);
505 
506  res = AVERROR(errno);
507  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_DQBUF): %s\n",
508  av_err2str(res));
509  return res;
510  }
511 
512  buf_ts = buf.timestamp;
513 
514  if (buf.index >= s->buffers) {
515  av_log(ctx, AV_LOG_ERROR, "Invalid buffer index received.\n");
516  return AVERROR(EINVAL);
517  }
519  // always keep at least one buffer queued
521 
522 #ifdef V4L2_BUF_FLAG_ERROR
523  if (buf.flags & V4L2_BUF_FLAG_ERROR) {
524  av_log(ctx, AV_LOG_WARNING,
525  "Dequeued v4l2 buffer contains corrupted data (%d bytes).\n",
526  buf.bytesused);
527  buf.bytesused = 0;
528  } else
529 #endif
530  {
531  /* CPIA is a compressed format and we don't know the exact number of bytes
532  * used by a frame, so set it here as the driver announces it. */
533  if (ctx->video_codec_id == AV_CODEC_ID_CPIA)
534  s->frame_size = buf.bytesused;
535 
536  if (s->frame_size > 0 && buf.bytesused != s->frame_size) {
537  av_log(ctx, AV_LOG_ERROR,
538  "Dequeued v4l2 buffer contains %d bytes, but %d were expected. Flags: 0x%08X.\n",
539  buf.bytesused, s->frame_size, buf.flags);
540  enqueue_buffer(s, &buf);
541  return AVERROR_INVALIDDATA;
542  }
543  }
544 
545  /* Image is at s->buff_start[buf.index] */
546  if (atomic_load(&s->buffers_queued) == FFMAX(s->buffers / 8, 1)) {
547  /* when we start getting low on queued buffers, fall back on copying data */
548  res = av_new_packet(pkt, buf.bytesused);
549  if (res < 0) {
550  av_log(ctx, AV_LOG_ERROR, "Error allocating a packet.\n");
551  enqueue_buffer(s, &buf);
552  return res;
553  }
554  memcpy(pkt->data, s->buf_start[buf.index], buf.bytesused);
555 
556  res = enqueue_buffer(s, &buf);
557  if (res) {
558  av_packet_unref(pkt);
559  return res;
560  }
561  } else {
562  struct buff_data *buf_descriptor;
563 
564  pkt->data = s->buf_start[buf.index];
565  pkt->size = buf.bytesused;
566 
567  buf_descriptor = av_malloc(sizeof(struct buff_data));
568  if (!buf_descriptor) {
569  /* Something went wrong... Since av_malloc() failed, we cannot even
570  * allocate a buffer for memcpying into it
571  */
572  av_log(ctx, AV_LOG_ERROR, "Failed to allocate a buffer descriptor\n");
573  enqueue_buffer(s, &buf);
574 
575  return AVERROR(ENOMEM);
576  }
577  buf_descriptor->index = buf.index;
578  buf_descriptor->s = s;
579 
580  pkt->buf = av_buffer_create(pkt->data, pkt->size, mmap_release_buffer,
581  buf_descriptor, 0);
582  if (!pkt->buf) {
583  av_log(ctx, AV_LOG_ERROR, "Failed to create a buffer\n");
584  enqueue_buffer(s, &buf);
585  av_freep(&buf_descriptor);
586  return AVERROR(ENOMEM);
587  }
588  }
589  pkt->pts = buf_ts.tv_sec * INT64_C(1000000) + buf_ts.tv_usec;
590  convert_timestamp(ctx, &pkt->pts);
591 
592  return pkt->size;
593 }
594 
595 static int mmap_start(AVFormatContext *ctx)
596 {
597  struct video_data *s = ctx->priv_data;
598  enum v4l2_buf_type type;
599  int i, res;
600 
601  for (i = 0; i < s->buffers; i++) {
602  struct v4l2_buffer buf = {
603  .type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
604  .index = i,
605  .memory = V4L2_MEMORY_MMAP
606  };
607 
608  if (v4l2_ioctl(s->fd, VIDIOC_QBUF, &buf) < 0) {
609  res = AVERROR(errno);
610  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF): %s\n",
611  av_err2str(res));
612  return res;
613  }
614  }
616 
617  type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
618  if (v4l2_ioctl(s->fd, VIDIOC_STREAMON, &type) < 0) {
619  res = AVERROR(errno);
620  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_STREAMON): %s\n",
621  av_err2str(res));
622  return res;
623  }
624 
625  return 0;
626 }
627 
628 static void mmap_close(struct video_data *s)
629 {
630  enum v4l2_buf_type type;
631  int i;
632 
633  type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
634  /* We do not check for the result, because we could
635  * not do anything about it anyway...
636  */
637  v4l2_ioctl(s->fd, VIDIOC_STREAMOFF, &type);
638  for (i = 0; i < s->buffers; i++) {
639  v4l2_munmap(s->buf_start[i], s->buf_len[i]);
640  }
641  av_freep(&s->buf_start);
642  av_freep(&s->buf_len);
643 }
644 
646 {
647  struct video_data *s = ctx->priv_data;
648  struct v4l2_standard standard = { 0 };
649  struct v4l2_streamparm streamparm = { 0 };
650  struct v4l2_fract *tpf;
651  AVRational framerate_q = { 0 };
652  int i, ret;
653 
654  if (s->framerate &&
655  (ret = av_parse_video_rate(&framerate_q, s->framerate)) < 0) {
656  av_log(ctx, AV_LOG_ERROR, "Could not parse framerate '%s'.\n",
657  s->framerate);
658  return ret;
659  }
660 
661  if (s->standard) {
662  if (s->std_id) {
663  ret = 0;
664  av_log(ctx, AV_LOG_DEBUG, "Setting standard: %s\n", s->standard);
665  /* set tv standard */
666  for (i = 0; ; i++) {
667  standard.index = i;
668  if (v4l2_ioctl(s->fd, VIDIOC_ENUMSTD, &standard) < 0) {
669  ret = AVERROR(errno);
670  break;
671  }
672  if (!av_strcasecmp(standard.name, s->standard))
673  break;
674  }
675  if (ret < 0) {
676  av_log(ctx, AV_LOG_ERROR, "Unknown or unsupported standard '%s'\n", s->standard);
677  return ret;
678  }
679 
680  if (v4l2_ioctl(s->fd, VIDIOC_S_STD, &standard.id) < 0) {
681  ret = AVERROR(errno);
682  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_S_STD): %s\n", av_err2str(ret));
683  return ret;
684  }
685  } else {
686  av_log(ctx, AV_LOG_WARNING,
687  "This device does not support any standard\n");
688  }
689  }
690 
691  /* get standard */
692  if (v4l2_ioctl(s->fd, VIDIOC_G_STD, &s->std_id) == 0) {
693  tpf = &standard.frameperiod;
694  for (i = 0; ; i++) {
695  standard.index = i;
696  if (v4l2_ioctl(s->fd, VIDIOC_ENUMSTD, &standard) < 0) {
697  ret = AVERROR(errno);
698  if (ret == AVERROR(EINVAL)
699 #ifdef ENODATA
700  || ret == AVERROR(ENODATA)
701 #endif
702  ) {
703  tpf = &streamparm.parm.capture.timeperframe;
704  break;
705  }
706  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_ENUMSTD): %s\n", av_err2str(ret));
707  return ret;
708  }
709  if (standard.id == s->std_id) {
710  av_log(ctx, AV_LOG_DEBUG,
711  "Current standard: %s, id: %"PRIx64", frameperiod: %d/%d\n",
712  standard.name, (uint64_t)standard.id, tpf->numerator, tpf->denominator);
713  break;
714  }
715  }
716  } else {
717  tpf = &streamparm.parm.capture.timeperframe;
718  }
719 
720  streamparm.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
721  if (v4l2_ioctl(s->fd, VIDIOC_G_PARM, &streamparm) < 0) {
722  ret = AVERROR(errno);
723  av_log(ctx, AV_LOG_WARNING, "ioctl(VIDIOC_G_PARM): %s\n", av_err2str(ret));
724  } else if (framerate_q.num && framerate_q.den) {
725  if (streamparm.parm.capture.capability & V4L2_CAP_TIMEPERFRAME) {
726  tpf = &streamparm.parm.capture.timeperframe;
727 
728  av_log(ctx, AV_LOG_DEBUG, "Setting time per frame to %d/%d\n",
729  framerate_q.den, framerate_q.num);
730  tpf->numerator = framerate_q.den;
731  tpf->denominator = framerate_q.num;
732 
733  if (v4l2_ioctl(s->fd, VIDIOC_S_PARM, &streamparm) < 0) {
734  ret = AVERROR(errno);
735  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_S_PARM): %s\n",
736  av_err2str(ret));
737  return ret;
738  }
739 
740  if (framerate_q.num != tpf->denominator ||
741  framerate_q.den != tpf->numerator) {
742  av_log(ctx, AV_LOG_INFO,
743  "The driver changed the time per frame from "
744  "%d/%d to %d/%d\n",
745  framerate_q.den, framerate_q.num,
746  tpf->numerator, tpf->denominator);
747  }
748  } else {
749  av_log(ctx, AV_LOG_WARNING,
750  "The driver does not permit changing the time per frame\n");
751  }
752  }
753  if (tpf->denominator > 0 && tpf->numerator > 0) {
754  ctx->streams[0]->avg_frame_rate.num = tpf->denominator;
755  ctx->streams[0]->avg_frame_rate.den = tpf->numerator;
756  ctx->streams[0]->r_frame_rate = ctx->streams[0]->avg_frame_rate;
757  } else
758  av_log(ctx, AV_LOG_WARNING, "Time per frame unknown\n");
759 
760  return 0;
761 }
762 
764  enum AVPixelFormat pix_fmt,
765  int *width,
766  int *height,
767  uint32_t *desired_format,
768  enum AVCodecID *codec_id)
769 {
770  int ret, i;
771 
772  *desired_format = ff_fmt_ff2v4l(pix_fmt, ctx->video_codec_id);
773 
774  if (*desired_format) {
775  ret = device_init(ctx, width, height, *desired_format);
776  if (ret < 0) {
777  *desired_format = 0;
778  if (ret != AVERROR(EINVAL))
779  return ret;
780  }
781  }
782 
783  if (!*desired_format) {
784  for (i = 0; ff_fmt_conversion_table[i].codec_id != AV_CODEC_ID_NONE; i++) {
785  if (ctx->video_codec_id == AV_CODEC_ID_NONE ||
787  av_log(ctx, AV_LOG_DEBUG, "Trying to set codec:%s pix_fmt:%s\n",
789  (char *)av_x_if_null(av_get_pix_fmt_name(ff_fmt_conversion_table[i].ff_fmt), "none"));
790 
791  *desired_format = ff_fmt_conversion_table[i].v4l2_fmt;
792  ret = device_init(ctx, width, height, *desired_format);
793  if (ret >= 0)
794  break;
795  else if (ret != AVERROR(EINVAL))
796  return ret;
797  *desired_format = 0;
798  }
799  }
800 
801  if (*desired_format == 0) {
802  av_log(ctx, AV_LOG_ERROR, "Cannot find a proper format for "
803  "codec '%s' (id %d), pixel format '%s' (id %d)\n",
805  (char *)av_x_if_null(av_get_pix_fmt_name(pix_fmt), "none"), pix_fmt);
806  ret = AVERROR(EINVAL);
807  }
808  }
809 
810  *codec_id = ff_fmt_v4l2codec(*desired_format);
811  av_assert0(*codec_id != AV_CODEC_ID_NONE);
812  return ret;
813 }
814 
816 {
817  if (av_strstart(p->filename, "/dev/video", NULL))
818  return AVPROBE_SCORE_MAX - 1;
819  return 0;
820 }
821 
823 {
824  struct video_data *s = ctx->priv_data;
825  AVStream *st;
826  int res = 0;
827  uint32_t desired_format;
830  struct v4l2_input input = { 0 };
831 
832  st = avformat_new_stream(ctx, NULL);
833  if (!st)
834  return AVERROR(ENOMEM);
835 
836 #if CONFIG_LIBV4L2
837  /* silence libv4l2 logging. if fopen() fails v4l2_log_file will be NULL
838  and errors will get sent to stderr */
839  if (s->use_libv4l2)
840  v4l2_log_file = fopen("/dev/null", "w");
841 #endif
842 
843  s->fd = device_open(ctx, ctx->url);
844  if (s->fd < 0)
845  return s->fd;
846 
847  if (s->channel != -1) {
848  /* set video input */
849  av_log(ctx, AV_LOG_DEBUG, "Selecting input_channel: %d\n", s->channel);
850  if (v4l2_ioctl(s->fd, VIDIOC_S_INPUT, &s->channel) < 0) {
851  res = AVERROR(errno);
852  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_S_INPUT): %s\n", av_err2str(res));
853  goto fail;
854  }
855  } else {
856  /* get current video input */
857  if (v4l2_ioctl(s->fd, VIDIOC_G_INPUT, &s->channel) < 0) {
858  res = AVERROR(errno);
859  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_G_INPUT): %s\n", av_err2str(res));
860  goto fail;
861  }
862  }
863 
864  /* enum input */
865  input.index = s->channel;
866  if (v4l2_ioctl(s->fd, VIDIOC_ENUMINPUT, &input) < 0) {
867  res = AVERROR(errno);
868  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_ENUMINPUT): %s\n", av_err2str(res));
869  goto fail;
870  }
871  s->std_id = input.std;
872  av_log(ctx, AV_LOG_DEBUG, "Current input_channel: %d, input_name: %s, input_std: %"PRIx64"\n",
873  s->channel, input.name, (uint64_t)input.std);
874 
875  if (s->list_format) {
876  list_formats(ctx, s->list_format);
877  res = AVERROR_EXIT;
878  goto fail;
879  }
880 
881  if (s->list_standard) {
882  list_standards(ctx);
883  res = AVERROR_EXIT;
884  goto fail;
885  }
886 
887  avpriv_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
888 
889  if (s->pixel_format) {
891 
892  if (desc)
893  ctx->video_codec_id = desc->id;
894 
895  pix_fmt = av_get_pix_fmt(s->pixel_format);
896 
897  if (pix_fmt == AV_PIX_FMT_NONE && !desc) {
898  av_log(ctx, AV_LOG_ERROR, "No such input format: %s.\n",
899  s->pixel_format);
900 
901  res = AVERROR(EINVAL);
902  goto fail;
903  }
904  }
905 
906  if (!s->width && !s->height) {
907  struct v4l2_format fmt = { .type = V4L2_BUF_TYPE_VIDEO_CAPTURE };
908 
909  av_log(ctx, AV_LOG_VERBOSE,
910  "Querying the device for the current frame size\n");
911  if (v4l2_ioctl(s->fd, VIDIOC_G_FMT, &fmt) < 0) {
912  res = AVERROR(errno);
913  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_G_FMT): %s\n",
914  av_err2str(res));
915  goto fail;
916  }
917 
918  s->width = fmt.fmt.pix.width;
919  s->height = fmt.fmt.pix.height;
920  av_log(ctx, AV_LOG_VERBOSE,
921  "Setting frame size to %dx%d\n", s->width, s->height);
922  }
923 
924  res = device_try_init(ctx, pix_fmt, &s->width, &s->height, &desired_format, &codec_id);
925  if (res < 0)
926  goto fail;
927 
928  /* If no pixel_format was specified, the codec_id was not known up
929  * until now. Set video_codec_id in the context, as codec_id will
930  * not be available outside this function
931  */
932  if (codec_id != AV_CODEC_ID_NONE && ctx->video_codec_id == AV_CODEC_ID_NONE)
933  ctx->video_codec_id = codec_id;
934 
935  if ((res = av_image_check_size(s->width, s->height, 0, ctx)) < 0)
936  goto fail;
937 
938  s->pixelformat = desired_format;
939 
940  if ((res = v4l2_set_parameters(ctx)) < 0)
941  goto fail;
942 
943  st->codecpar->format = ff_fmt_v4l2ff(desired_format, codec_id);
944  if (st->codecpar->format != AV_PIX_FMT_NONE)
946  s->width, s->height, 1);
947 
948  if ((res = mmap_init(ctx)) ||
949  (res = mmap_start(ctx)) < 0)
950  goto fail;
951 
953 
955  st->codecpar->codec_id = codec_id;
956  if (codec_id == AV_CODEC_ID_RAWVIDEO)
957  st->codecpar->codec_tag =
959  else if (codec_id == AV_CODEC_ID_H264) {
961  }
962  if (desired_format == V4L2_PIX_FMT_YVU420)
963  st->codecpar->codec_tag = MKTAG('Y', 'V', '1', '2');
964  else if (desired_format == V4L2_PIX_FMT_YVU410)
965  st->codecpar->codec_tag = MKTAG('Y', 'V', 'U', '9');
966  st->codecpar->width = s->width;
967  st->codecpar->height = s->height;
968  if (st->avg_frame_rate.den)
969  st->codecpar->bit_rate = s->frame_size * av_q2d(st->avg_frame_rate) * 8;
970 
971  return 0;
972 
973 fail:
974  v4l2_close(s->fd);
975  return res;
976 }
977 
979 {
980 #if FF_API_CODED_FRAME && FF_API_LAVF_AVCTX
982  struct video_data *s = ctx->priv_data;
983  AVFrame *frame = ctx->streams[0]->codec->coded_frame;
985 #endif
986  int res;
987 
988  if ((res = mmap_read_frame(ctx, pkt)) < 0) {
989  return res;
990  }
991 
992 #if FF_API_CODED_FRAME && FF_API_LAVF_AVCTX
994  if (frame && s->interlaced) {
995  frame->interlaced_frame = 1;
996  frame->top_field_first = s->top_field_first;
997  }
999 #endif
1000 
1001  return pkt->size;
1002 }
1003 
1005 {
1006  struct video_data *s = ctx->priv_data;
1007 
1008  if (atomic_load(&s->buffers_queued) != s->buffers)
1009  av_log(ctx, AV_LOG_WARNING, "Some buffers are still owned by the caller on "
1010  "close.\n");
1011 
1012  mmap_close(s);
1013 
1014  v4l2_close(s->fd);
1015  return 0;
1016 }
1017 
1018 static int v4l2_is_v4l_dev(const char *name)
1019 {
1020  return !strncmp(name, "video", 5) ||
1021  !strncmp(name, "radio", 5) ||
1022  !strncmp(name, "vbi", 3) ||
1023  !strncmp(name, "v4l-subdev", 10);
1024 }
1025 
1027 {
1028  struct video_data *s = ctx->priv_data;
1029  DIR *dir;
1030  struct dirent *entry;
1031  AVDeviceInfo *device = NULL;
1032  struct v4l2_capability cap;
1033  int ret = 0;
1034 
1035  if (!device_list)
1036  return AVERROR(EINVAL);
1037 
1038  dir = opendir("/dev");
1039  if (!dir) {
1040  ret = AVERROR(errno);
1041  av_log(ctx, AV_LOG_ERROR, "Couldn't open the directory: %s\n", av_err2str(ret));
1042  return ret;
1043  }
1044  while ((entry = readdir(dir))) {
1045  char device_name[256];
1046 
1047  if (!v4l2_is_v4l_dev(entry->d_name))
1048  continue;
1049 
1050  snprintf(device_name, sizeof(device_name), "/dev/%s", entry->d_name);
1051  if ((s->fd = device_open(ctx, device_name)) < 0)
1052  continue;
1053 
1054  if (v4l2_ioctl(s->fd, VIDIOC_QUERYCAP, &cap) < 0) {
1055  ret = AVERROR(errno);
1056  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYCAP): %s\n", av_err2str(ret));
1057  goto fail;
1058  }
1059 
1060  device = av_mallocz(sizeof(AVDeviceInfo));
1061  if (!device) {
1062  ret = AVERROR(ENOMEM);
1063  goto fail;
1064  }
1065  device->device_name = av_strdup(device_name);
1066  device->device_description = av_strdup(cap.card);
1067  if (!device->device_name || !device->device_description) {
1068  ret = AVERROR(ENOMEM);
1069  goto fail;
1070  }
1071 
1072  if ((ret = av_dynarray_add_nofree(&device_list->devices,
1073  &device_list->nb_devices, device)) < 0)
1074  goto fail;
1075 
1076  v4l2_close(s->fd);
1077  s->fd = -1;
1078  continue;
1079 
1080  fail:
1081  if (device) {
1082  av_freep(&device->device_name);
1083  av_freep(&device->device_description);
1084  av_freep(&device);
1085  }
1086  if (s->fd >= 0)
1087  v4l2_close(s->fd);
1088  s->fd = -1;
1089  break;
1090  }
1091  closedir(dir);
1092  return ret;
1093 }
1094 
1095 #define OFFSET(x) offsetof(struct video_data, x)
1096 #define DEC AV_OPT_FLAG_DECODING_PARAM
1097 
1098 static const AVOption options[] = {
1099  { "standard", "set TV standard, used only by analog frame grabber", OFFSET(standard), AV_OPT_TYPE_STRING, {.str = NULL }, 0, 0, DEC },
1100  { "channel", "set TV channel, used only by frame grabber", OFFSET(channel), AV_OPT_TYPE_INT, {.i64 = -1 }, -1, INT_MAX, DEC },
1101  { "video_size", "set frame size", OFFSET(width), AV_OPT_TYPE_IMAGE_SIZE, {.str = NULL}, 0, 0, DEC },
1102  { "pixel_format", "set preferred pixel format", OFFSET(pixel_format), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
1103  { "input_format", "set preferred pixel format (for raw video) or codec name", OFFSET(pixel_format), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
1104  { "framerate", "set frame rate", OFFSET(framerate), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
1105 
1106  { "list_formats", "list available formats and exit", OFFSET(list_format), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, DEC, "list_formats" },
1107  { "all", "show all available formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.i64 = V4L_ALLFORMATS }, 0, INT_MAX, DEC, "list_formats" },
1108  { "raw", "show only non-compressed formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.i64 = V4L_RAWFORMATS }, 0, INT_MAX, DEC, "list_formats" },
1109  { "compressed", "show only compressed formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.i64 = V4L_COMPFORMATS }, 0, INT_MAX, DEC, "list_formats" },
1110 
1111  { "list_standards", "list supported standards and exit", OFFSET(list_standard), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 1, DEC, "list_standards" },
1112  { "all", "show all supported standards", OFFSET(list_standard), AV_OPT_TYPE_CONST, {.i64 = 1 }, 0, 0, DEC, "list_standards" },
1113 
1114  { "timestamps", "set type of timestamps for grabbed frames", OFFSET(ts_mode), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 2, DEC, "timestamps" },
1115  { "ts", "set type of timestamps for grabbed frames", OFFSET(ts_mode), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 2, DEC, "timestamps" },
1116  { "default", "use timestamps from the kernel", OFFSET(ts_mode), AV_OPT_TYPE_CONST, {.i64 = V4L_TS_DEFAULT }, 0, 2, DEC, "timestamps" },
1117  { "abs", "use absolute timestamps (wall clock)", OFFSET(ts_mode), AV_OPT_TYPE_CONST, {.i64 = V4L_TS_ABS }, 0, 2, DEC, "timestamps" },
1118  { "mono2abs", "force conversion from monotonic to absolute timestamps", OFFSET(ts_mode), AV_OPT_TYPE_CONST, {.i64 = V4L_TS_MONO2ABS }, 0, 2, DEC, "timestamps" },
1119  { "use_libv4l2", "use libv4l2 (v4l-utils) conversion functions", OFFSET(use_libv4l2), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, DEC },
1120  { NULL },
1121 };
1122 
1123 static const AVClass v4l2_class = {
1124  .class_name = "V4L2 indev",
1125  .item_name = av_default_item_name,
1126  .option = options,
1127  .version = LIBAVUTIL_VERSION_INT,
1129 };
1130 
1132  .name = "video4linux2,v4l2",
1133  .long_name = NULL_IF_CONFIG_SMALL("Video4Linux2 device grab"),
1134  .priv_data_size = sizeof(struct video_data),
1135  .read_probe = v4l2_read_probe,
1136  .read_header = v4l2_read_header,
1137  .read_packet = v4l2_read_packet,
1138  .read_close = v4l2_read_close,
1139  .get_device_list = v4l2_get_device_list,
1140  .flags = AVFMT_NOFILE,
1141  .priv_class = &v4l2_class,
1142 };
int(* open_f)(const char *file, int oflag,...)
Definition: v4l2.c:95
#define NULL
Definition: coverity.c:32
Structure describes basic parameters of the device.
Definition: avdevice.h:452
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
#define v4l2_mmap
static enum AVPixelFormat pix_fmt
This structure describes decoded (raw) audio or video data.
Definition: frame.h:226
int frame_size
Definition: v4l2.c:75
int av_parse_video_rate(AVRational *rate, const char *arg)
Parse str and store the detected values in *rate.
Definition: parseutils.c:179
#define atomic_store(object, desired)
Definition: stdatomic.h:85
AVOption.
Definition: opt.h:246
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:101
int(* dup_f)(int fd)
Definition: v4l2.c:97
ssize_t(* read_f)(int fd, void *buffer, size_t n)
Definition: v4l2.c:99
char * device_description
human friendly name
Definition: avdevice.h:454
static int device_init(AVFormatContext *ctx, int *width, int *height, uint32_t pixelformat)
Definition: v4l2.c:188
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
const char * filename
Definition: avformat.h:449
int(* close_f)(int fd)
Definition: v4l2.c:96
void avpriv_set_pts_info(AVStream *s, 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:4882
const char * desc
Definition: nvenc.c:65
#define v4l2_open
char * pixel_format
Set by a private option.
Definition: v4l2.c:89
char * device_name
device name, format depends on device
Definition: avdevice.h:453
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3900
int num
Numerator.
Definition: rational.h:59
int size
Definition: avcodec.h:1446
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:191
enum AVCodecID codec_id
Definition: v4l2-common.h:51
static int enqueue_buffer(struct video_data *s, struct v4l2_buffer *buf)
Definition: v4l2.c:399
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:236
static int device_try_init(AVFormatContext *ctx, enum AVPixelFormat pix_fmt, int *width, int *height, uint32_t *desired_format, enum AVCodecID *codec_id)
Definition: v4l2.c:763
static void list_formats(AVFormatContext *ctx, int type)
Definition: v4l2.c:271
uint32_t ff_fmt_ff2v4l(enum AVPixelFormat pix_fmt, enum AVCodecID codec_id)
Definition: v4l2-common.c:70
static AVPacket pkt
double ff_timefilter_eval(TimeFilter *self, double delta)
Evaluate the filter at a specified time.
Definition: timefilter.c:88
intptr_t atomic_int
Definition: stdatomic.h:55
unsigned int * buf_len
Definition: v4l2.c:85
const struct fmt_map ff_fmt_conversion_table[]
Definition: v4l2-common.c:21
Format I/O context.
Definition: avformat.h:1351
int channel
Definition: v4l2.c:88
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:72
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
#define AVFMT_FLAG_NONBLOCK
Do not block when reading packets from input.
Definition: avformat.h:1485
v4l2_std_id std_id
Definition: v4l2.c:87
#define V4L_TS_ABS
Autodetect the kind of timestamps returned by the kernel and convert to absolute (wall clock) timesta...
Definition: v4l2.c:56
Opaque type representing a time filter state.
Definition: timefilter.c:30
uint8_t
#define av_malloc(s)
int width
Video only.
Definition: avcodec.h:3966
static int mmap_read_frame(AVFormatContext *ctx, AVPacket *pkt)
Definition: v4l2.c:488
static int init_convert_timestamp(AVFormatContext *ctx, int64_t ts)
Definition: v4l2.c:434
unsigned int avcodec_pix_fmt_to_codec_tag(enum AVPixelFormat pix_fmt)
Return a value representing the fourCC code associated to the pixel format pix_fmt, or 0 if no associated fourCC code can be found.
Definition: raw.c:300
#define v4l2_close
enum AVStreamParseType need_parsing
Definition: avformat.h:1092
static int v4l2_read_header(AVFormatContext *ctx)
Definition: v4l2.c:822
static int mmap_start(AVFormatContext *ctx)
Definition: v4l2.c:595
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4455
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1419
static AVFrame * frame
char * standard
Definition: v4l2.c:86
static const int desired_video_buffers
Definition: v4l2.c:42
#define height
int flags
Flags modifying the (de)muxer behaviour.
Definition: avformat.h:1482
uint8_t * data
Definition: avcodec.h:1445
static int v4l2_is_v4l_dev(const char *name)
Definition: v4l2.c:1018
static double av_q2d(AVRational a)
Convert an AVRational to a double.
Definition: rational.h:104
#define AV_LOG_VERBOSE
Detailed information.
Definition: log.h:192
int interlaced_frame
The content of the picture is interlaced.
Definition: frame.h:373
int av_dynarray_add_nofree(void *tab_ptr, int *nb_ptr, void *elem)
Add an element to a dynamic array.
Definition: mem.c:294
#define V4L_TS_DEFAULT
Return timestamps to the user exactly as returned by the kernel.
Definition: v4l2.c:51
static int v4l2_set_parameters(AVFormatContext *ctx)
Definition: v4l2.c:645
enum AVCodecID video_codec_id
Forced video codec_id.
Definition: avformat.h:1537
#define av_log(a,...)
static int first_field(const struct video_data *s)
Definition: v4l2.c:230
#define V4L_TS_CONVERT_READY
Once the kind of timestamps returned by the kernel have been detected, the value of the timefilter (N...
Definition: v4l2.c:68
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: avcodec.h:3929
static void * av_x_if_null(const void *p, const void *x)
Return x default pointer in case p is NULL.
Definition: avutil.h:308
static int v4l2_get_device_list(AVFormatContext *ctx, AVDeviceInfoList *device_list)
Definition: v4l2.c:1026
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
int height
Definition: v4l2.c:74
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:86
int interlaced
Definition: v4l2.c:76
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:431
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition: avcodec.h:215
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
static int device_open(AVFormatContext *ctx, const char *device_path)
Definition: v4l2.c:109
#define atomic_load(object)
Definition: stdatomic.h:93
#define AVERROR(e)
Definition: error.h:43
#define v4l2_munmap
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
char * url
input or output URL.
Definition: avformat.h:1447
static const AVOption options[]
Definition: v4l2.c:1098
const char * r
Definition: vf_curves.c:114
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:197
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3896
AVBufferRef * buf
A reference to the reference-counted buffer where the packet data is stored.
Definition: avcodec.h:1428
void ** buf_start
Definition: v4l2.c:84
GLsizei GLsizei * length
Definition: opengl_enc.c:115
AVBufferRef * av_buffer_create(uint8_t *data, int size, void(*free)(void *opaque, uint8_t *data), void *opaque, int flags)
Create an AVBuffer from an existing array.
Definition: buffer.c:28
int use_libv4l2
Definition: v4l2.c:94
AVDeviceInfo ** devices
list of autodetected devices
Definition: avdevice.h:461
static const uint8_t offset[127][2]
Definition: vf_spp.c:92
#define OFFSET(x)
Definition: v4l2.c:1095
AVRational avg_frame_rate
Average framerate.
Definition: avformat.h:947
#define FFMAX(a, b)
Definition: common.h:94
#define fail()
Definition: checkasm.h:117
#define V4L_TS_MONO2ABS
Assume kernel timestamps are from the monotonic clock and convert to absolute timestamps.
Definition: v4l2.c:61
const AVCodecDescriptor * avcodec_descriptor_get(enum AVCodecID id)
Definition: codec_desc.c:3199
TimeFilter * timefilter
Definition: v4l2.c:79
int av_image_check_size(unsigned int w, unsigned int h, int log_offset, void *log_ctx)
Check if the given dimension of an image is valid, meaning that all bytes of the image can be address...
Definition: imgutils.c:282
#define E
Definition: avdct.c:32
#define AV_TIME_BASE
Internal time base represented as integer.
Definition: avutil.h:254
static void list_standards(AVFormatContext *ctx)
Definition: v4l2.c:309
int av_strcasecmp(const char *a, const char *b)
Locale-independent case-insensitive compare.
Definition: avstring.c:213
#define width
static int convert_timestamp(AVFormatContext *ctx, int64_t *ts)
Definition: v4l2.c:467
static void mmap_close(struct video_data *s)
Definition: v4l2.c:628
#define av_err2str(errnum)
Convenience macro, the return value should be used only directly in function arguments but never stan...
Definition: error.h:119
AVFormatContext * ctx
Definition: movenc.c:48
int ts_mode
Definition: v4l2.c:78
#define s(width, name)
Definition: cbs_vp9.c:257
int n
Definition: avisynth_c.h:684
enum AVCodecID codec_id
Definition: vaapi_decode.c:364
#define AVERROR_EXIT
Immediate exit was requested; the called function should not be restarted.
Definition: error.h:56
int list_format
Set by a private option.
Definition: v4l2.c:90
#define v4l2_ioctl
const AVCodecDescriptor * avcodec_descriptor_get_by_name(const char *name)
Definition: codec_desc.c:3214
const char * avcodec_get_name(enum AVCodecID id)
Get the name of a codec.
Definition: utils.c:1135
int64_t av_gettime(void)
Get the current time in microseconds.
Definition: time.c:39
#define SET_WRAPPERS(prefix)
Stream structure.
Definition: avformat.h:874
#define atomic_fetch_add(object, operand)
Definition: stdatomic.h:131
#define AV_LOG_INFO
Standard information.
Definition: log.h:187
TimeFilter * ff_timefilter_new(double time_base, double period, double bandwidth)
Create a new Delay Locked Loop time filter.
Definition: timefilter.c:46
char * av_strdup(const char *s)
Duplicate a string.
Definition: mem.c:251
atomic_int buffers_queued
Definition: v4l2.c:83
#define V4L_ALLFORMATS
Definition: v4l2.c:44
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:598
void * buf
Definition: avisynth_c.h:690
GLint GLenum type
Definition: opengl_enc.c:105
int fd
Definition: v4l2.c:72
struct video_data * s
Definition: v4l2.c:105
int64_t last_time_m
Definition: v4l2.c:80
Describe the class of an AVClass context structure.
Definition: log.h:67
static int v4l2_read_close(AVFormatContext *ctx)
Definition: v4l2.c:1004
Rational number (pair of numerator and denominator).
Definition: rational.h:58
int width
Definition: v4l2.c:74
const char * name
Name of the codec described by this descriptor.
Definition: avcodec.h:716
#define snprintf
Definition: snprintf.h:34
offset must point to two consecutive integers
Definition: opt.h:233
This structure contains the data a format has to probe a file.
Definition: avformat.h:448
int list_standard
Set by a private option.
Definition: v4l2.c:91
List of devices.
Definition: avdevice.h:460
static int mmap_init(AVFormatContext *ctx)
Definition: v4l2.c:333
This struct describes the properties of a single codec described by an AVCodecID. ...
Definition: avcodec.h:708
full parsing and repack of the first frame only, only implemented for H.264 currently ...
Definition: avformat.h:796
static const AVClass v4l2_class
Definition: v4l2.c:1123
static int v4l2_read_packet(AVFormatContext *ctx, AVPacket *pkt)
Definition: v4l2.c:978
int64_t av_gettime_relative(void)
Get the current time in microseconds since some unspecified starting point.
Definition: time.c:56
#define flags(name, subs,...)
Definition: cbs_av1.c:596
int index
Definition: v4l2.c:106
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:460
int av_strstart(const char *str, const char *pfx, const char **ptr)
Return non-zero if pfx is a prefix of str.
Definition: avstring.c:34
int
double ff_timefilter_update(TimeFilter *self, double system_time, double period)
Update the filter.
Definition: timefilter.c:72
#define FF_DISABLE_DEPRECATION_WARNINGS
Definition: internal.h:84
int buffers
Definition: v4l2.c:82
#define AVFMT_NOFILE
Demuxer will use avio_open, no opened file should be provided by the caller.
Definition: avformat.h:465
char * framerate
Set by a private option.
Definition: v4l2.c:92
#define V4L_COMPFORMATS
Definition: v4l2.c:46
channel
Use these values when setting the channel map with ebur128_set_channel().
Definition: ebur128.h:39
enum AVCodecID ff_fmt_v4l2codec(uint32_t v4l2_fmt)
Definition: v4l2-common.c:100
int den
Denominator.
Definition: rational.h:60
enum AVCodecID id
Definition: avcodec.h:709
#define av_free(p)
#define FF_ENABLE_DEPRECATION_WARNINGS
Definition: internal.h:85
#define V4L_RAWFORMATS
Definition: v4l2.c:45
int top_field_first
If the content is interlaced, is top field displayed first.
Definition: frame.h:378
void * priv_data
Format private data.
Definition: avformat.h:1379
enum AVPixelFormat ff_fmt_v4l2ff(uint32_t v4l2_fmt, enum AVCodecID codec_id)
Definition: v4l2-common.c:86
AVInputFormat ff_v4l2_demuxer
Definition: v4l2.c:1131
#define DEC
Definition: v4l2.c:1096
#define av_freep(p)
void INT64 start
Definition: avisynth_c.h:690
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:647
uint32_t v4l2_fmt
Definition: v4l2-common.h:52
static void mmap_release_buffer(void *opaque, uint8_t *data)
Definition: v4l2.c:413
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1021
#define av_malloc_array(a, b)
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: avcodec.h:3904
enum AVPixelFormat av_get_pix_fmt(const char *name)
Return the pixel format corresponding to name.
Definition: pixdesc.c:2374
const char * av_get_pix_fmt_name(enum AVPixelFormat pix_fmt)
Return the short name for a pixel format, NULL in case pix_fmt is unknown.
Definition: pixdesc.c:2362
int pixelformat
Definition: v4l2.c:73
int(* munmap_f)(void *_start, size_t length)
Definition: v4l2.c:101
static int v4l2_read_probe(AVProbeData *p)
Definition: v4l2.c:815
#define MKTAG(a, b, c, d)
Definition: common.h:366
AVRational r_frame_rate
Real base framerate of the stream.
Definition: avformat.h:998
int nb_devices
number of autodetected devices
Definition: avdevice.h:462
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
This structure stores compressed data.
Definition: avcodec.h:1422
int(* ioctl_f)(int fd, unsigned long int request,...)
Definition: v4l2.c:98
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1438
GLuint buffer
Definition: opengl_enc.c:102
#define tb
Definition: regdef.h:68
const char * name
Definition: opengl_enc.c:103
int top_field_first
Definition: v4l2.c:77