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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 
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(ctx->filename, 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  ctx->filename, 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  int res;
496 
497  pkt->size = 0;
498 
499  /* FIXME: Some special treatment might be needed in case of loss of signal... */
500  while ((res = v4l2_ioctl(s->fd, VIDIOC_DQBUF, &buf)) < 0 && (errno == EINTR));
501  if (res < 0) {
502  if (errno == EAGAIN)
503  return AVERROR(EAGAIN);
504 
505  res = AVERROR(errno);
506  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_DQBUF): %s\n",
507  av_err2str(res));
508  return res;
509  }
510 
511  if (buf.index >= s->buffers) {
512  av_log(ctx, AV_LOG_ERROR, "Invalid buffer index received.\n");
513  return AVERROR(EINVAL);
514  }
516  // always keep at least one buffer queued
518 
519 #ifdef V4L2_BUF_FLAG_ERROR
520  if (buf.flags & V4L2_BUF_FLAG_ERROR) {
521  av_log(ctx, AV_LOG_WARNING,
522  "Dequeued v4l2 buffer contains corrupted data (%d bytes).\n",
523  buf.bytesused);
524  buf.bytesused = 0;
525  } else
526 #endif
527  {
528  /* CPIA is a compressed format and we don't know the exact number of bytes
529  * used by a frame, so set it here as the driver announces it. */
530  if (ctx->video_codec_id == AV_CODEC_ID_CPIA)
531  s->frame_size = buf.bytesused;
532 
533  if (s->frame_size > 0 && buf.bytesused != s->frame_size) {
534  av_log(ctx, AV_LOG_ERROR,
535  "Dequeued v4l2 buffer contains %d bytes, but %d were expected. Flags: 0x%08X.\n",
536  buf.bytesused, s->frame_size, buf.flags);
537  enqueue_buffer(s, &buf);
538  return AVERROR_INVALIDDATA;
539  }
540  }
541 
542  /* Image is at s->buff_start[buf.index] */
543  if (atomic_load(&s->buffers_queued) == FFMAX(s->buffers / 8, 1)) {
544  /* when we start getting low on queued buffers, fall back on copying data */
545  res = av_new_packet(pkt, buf.bytesused);
546  if (res < 0) {
547  av_log(ctx, AV_LOG_ERROR, "Error allocating a packet.\n");
548  enqueue_buffer(s, &buf);
549  return res;
550  }
551  memcpy(pkt->data, s->buf_start[buf.index], buf.bytesused);
552 
553  res = enqueue_buffer(s, &buf);
554  if (res) {
555  av_packet_unref(pkt);
556  return res;
557  }
558  } else {
559  struct buff_data *buf_descriptor;
560 
561  pkt->data = s->buf_start[buf.index];
562  pkt->size = buf.bytesused;
563 
564  buf_descriptor = av_malloc(sizeof(struct buff_data));
565  if (!buf_descriptor) {
566  /* Something went wrong... Since av_malloc() failed, we cannot even
567  * allocate a buffer for memcpying into it
568  */
569  av_log(ctx, AV_LOG_ERROR, "Failed to allocate a buffer descriptor\n");
570  enqueue_buffer(s, &buf);
571 
572  return AVERROR(ENOMEM);
573  }
574  buf_descriptor->index = buf.index;
575  buf_descriptor->s = s;
576 
577  pkt->buf = av_buffer_create(pkt->data, pkt->size, mmap_release_buffer,
578  buf_descriptor, 0);
579  if (!pkt->buf) {
580  av_log(ctx, AV_LOG_ERROR, "Failed to create a buffer\n");
581  enqueue_buffer(s, &buf);
582  av_freep(&buf_descriptor);
583  return AVERROR(ENOMEM);
584  }
585  }
586  pkt->pts = buf.timestamp.tv_sec * INT64_C(1000000) + buf.timestamp.tv_usec;
587  convert_timestamp(ctx, &pkt->pts);
588 
589  return pkt->size;
590 }
591 
592 static int mmap_start(AVFormatContext *ctx)
593 {
594  struct video_data *s = ctx->priv_data;
595  enum v4l2_buf_type type;
596  int i, res;
597 
598  for (i = 0; i < s->buffers; i++) {
599  struct v4l2_buffer buf = {
600  .type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
601  .index = i,
602  .memory = V4L2_MEMORY_MMAP
603  };
604 
605  if (v4l2_ioctl(s->fd, VIDIOC_QBUF, &buf) < 0) {
606  res = AVERROR(errno);
607  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF): %s\n",
608  av_err2str(res));
609  return res;
610  }
611  }
613 
614  type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
615  if (v4l2_ioctl(s->fd, VIDIOC_STREAMON, &type) < 0) {
616  res = AVERROR(errno);
617  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_STREAMON): %s\n",
618  av_err2str(res));
619  return res;
620  }
621 
622  return 0;
623 }
624 
625 static void mmap_close(struct video_data *s)
626 {
627  enum v4l2_buf_type type;
628  int i;
629 
630  type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
631  /* We do not check for the result, because we could
632  * not do anything about it anyway...
633  */
634  v4l2_ioctl(s->fd, VIDIOC_STREAMOFF, &type);
635  for (i = 0; i < s->buffers; i++) {
636  v4l2_munmap(s->buf_start[i], s->buf_len[i]);
637  }
638  av_freep(&s->buf_start);
639  av_freep(&s->buf_len);
640 }
641 
643 {
644  struct video_data *s = ctx->priv_data;
645  struct v4l2_standard standard = { 0 };
646  struct v4l2_streamparm streamparm = { 0 };
647  struct v4l2_fract *tpf;
648  AVRational framerate_q = { 0 };
649  int i, ret;
650 
651  if (s->framerate &&
652  (ret = av_parse_video_rate(&framerate_q, s->framerate)) < 0) {
653  av_log(ctx, AV_LOG_ERROR, "Could not parse framerate '%s'.\n",
654  s->framerate);
655  return ret;
656  }
657 
658  if (s->standard) {
659  if (s->std_id) {
660  ret = 0;
661  av_log(ctx, AV_LOG_DEBUG, "Setting standard: %s\n", s->standard);
662  /* set tv standard */
663  for (i = 0; ; i++) {
664  standard.index = i;
665  if (v4l2_ioctl(s->fd, VIDIOC_ENUMSTD, &standard) < 0) {
666  ret = AVERROR(errno);
667  break;
668  }
669  if (!av_strcasecmp(standard.name, s->standard))
670  break;
671  }
672  if (ret < 0) {
673  av_log(ctx, AV_LOG_ERROR, "Unknown or unsupported standard '%s'\n", s->standard);
674  return ret;
675  }
676 
677  if (v4l2_ioctl(s->fd, VIDIOC_S_STD, &standard.id) < 0) {
678  ret = AVERROR(errno);
679  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_S_STD): %s\n", av_err2str(ret));
680  return ret;
681  }
682  } else {
683  av_log(ctx, AV_LOG_WARNING,
684  "This device does not support any standard\n");
685  }
686  }
687 
688  /* get standard */
689  if (v4l2_ioctl(s->fd, VIDIOC_G_STD, &s->std_id) == 0) {
690  tpf = &standard.frameperiod;
691  for (i = 0; ; i++) {
692  standard.index = i;
693  if (v4l2_ioctl(s->fd, VIDIOC_ENUMSTD, &standard) < 0) {
694  ret = AVERROR(errno);
695  if (ret == AVERROR(EINVAL)
696 #ifdef ENODATA
697  || ret == AVERROR(ENODATA)
698 #endif
699  ) {
700  tpf = &streamparm.parm.capture.timeperframe;
701  break;
702  }
703  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_ENUMSTD): %s\n", av_err2str(ret));
704  return ret;
705  }
706  if (standard.id == s->std_id) {
707  av_log(ctx, AV_LOG_DEBUG,
708  "Current standard: %s, id: %"PRIx64", frameperiod: %d/%d\n",
709  standard.name, (uint64_t)standard.id, tpf->numerator, tpf->denominator);
710  break;
711  }
712  }
713  } else {
714  tpf = &streamparm.parm.capture.timeperframe;
715  }
716 
717  streamparm.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
718  if (v4l2_ioctl(s->fd, VIDIOC_G_PARM, &streamparm) < 0) {
719  ret = AVERROR(errno);
720  av_log(ctx, AV_LOG_WARNING, "ioctl(VIDIOC_G_PARM): %s\n", av_err2str(ret));
721  } else if (framerate_q.num && framerate_q.den) {
722  if (streamparm.parm.capture.capability & V4L2_CAP_TIMEPERFRAME) {
723  tpf = &streamparm.parm.capture.timeperframe;
724 
725  av_log(ctx, AV_LOG_DEBUG, "Setting time per frame to %d/%d\n",
726  framerate_q.den, framerate_q.num);
727  tpf->numerator = framerate_q.den;
728  tpf->denominator = framerate_q.num;
729 
730  if (v4l2_ioctl(s->fd, VIDIOC_S_PARM, &streamparm) < 0) {
731  ret = AVERROR(errno);
732  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_S_PARM): %s\n",
733  av_err2str(ret));
734  return ret;
735  }
736 
737  if (framerate_q.num != tpf->denominator ||
738  framerate_q.den != tpf->numerator) {
739  av_log(ctx, AV_LOG_INFO,
740  "The driver changed the time per frame from "
741  "%d/%d to %d/%d\n",
742  framerate_q.den, framerate_q.num,
743  tpf->numerator, tpf->denominator);
744  }
745  } else {
746  av_log(ctx, AV_LOG_WARNING,
747  "The driver does not permit changing the time per frame\n");
748  }
749  }
750  if (tpf->denominator > 0 && tpf->numerator > 0) {
751  ctx->streams[0]->avg_frame_rate.num = tpf->denominator;
752  ctx->streams[0]->avg_frame_rate.den = tpf->numerator;
753  ctx->streams[0]->r_frame_rate = ctx->streams[0]->avg_frame_rate;
754  } else
755  av_log(ctx, AV_LOG_WARNING, "Time per frame unknown\n");
756 
757  return 0;
758 }
759 
761  enum AVPixelFormat pix_fmt,
762  int *width,
763  int *height,
764  uint32_t *desired_format,
765  enum AVCodecID *codec_id)
766 {
767  int ret, i;
768 
769  *desired_format = ff_fmt_ff2v4l(pix_fmt, ctx->video_codec_id);
770 
771  if (*desired_format) {
772  ret = device_init(ctx, width, height, *desired_format);
773  if (ret < 0) {
774  *desired_format = 0;
775  if (ret != AVERROR(EINVAL))
776  return ret;
777  }
778  }
779 
780  if (!*desired_format) {
781  for (i = 0; ff_fmt_conversion_table[i].codec_id != AV_CODEC_ID_NONE; i++) {
782  if (ctx->video_codec_id == AV_CODEC_ID_NONE ||
784  av_log(ctx, AV_LOG_DEBUG, "Trying to set codec:%s pix_fmt:%s\n",
786  (char *)av_x_if_null(av_get_pix_fmt_name(ff_fmt_conversion_table[i].ff_fmt), "none"));
787 
788  *desired_format = ff_fmt_conversion_table[i].v4l2_fmt;
789  ret = device_init(ctx, width, height, *desired_format);
790  if (ret >= 0)
791  break;
792  else if (ret != AVERROR(EINVAL))
793  return ret;
794  *desired_format = 0;
795  }
796  }
797 
798  if (*desired_format == 0) {
799  av_log(ctx, AV_LOG_ERROR, "Cannot find a proper format for "
800  "codec '%s' (id %d), pixel format '%s' (id %d)\n",
802  (char *)av_x_if_null(av_get_pix_fmt_name(pix_fmt), "none"), pix_fmt);
803  ret = AVERROR(EINVAL);
804  }
805  }
806 
807  *codec_id = ff_fmt_v4l2codec(*desired_format);
808  av_assert0(*codec_id != AV_CODEC_ID_NONE);
809  return ret;
810 }
811 
813 {
814  if (av_strstart(p->filename, "/dev/video", NULL))
815  return AVPROBE_SCORE_MAX - 1;
816  return 0;
817 }
818 
820 {
821  struct video_data *s = ctx->priv_data;
822  AVStream *st;
823  int res = 0;
824  uint32_t desired_format;
827  struct v4l2_input input = { 0 };
828 
829  st = avformat_new_stream(ctx, NULL);
830  if (!st)
831  return AVERROR(ENOMEM);
832 
833 #if CONFIG_LIBV4L2
834  /* silence libv4l2 logging. if fopen() fails v4l2_log_file will be NULL
835  and errors will get sent to stderr */
836  if (s->use_libv4l2)
837  v4l2_log_file = fopen("/dev/null", "w");
838 #endif
839 
840  s->fd = device_open(ctx);
841  if (s->fd < 0)
842  return s->fd;
843 
844  if (s->channel != -1) {
845  /* set video input */
846  av_log(ctx, AV_LOG_DEBUG, "Selecting input_channel: %d\n", s->channel);
847  if (v4l2_ioctl(s->fd, VIDIOC_S_INPUT, &s->channel) < 0) {
848  res = AVERROR(errno);
849  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_S_INPUT): %s\n", av_err2str(res));
850  goto fail;
851  }
852  } else {
853  /* get current video input */
854  if (v4l2_ioctl(s->fd, VIDIOC_G_INPUT, &s->channel) < 0) {
855  res = AVERROR(errno);
856  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_G_INPUT): %s\n", av_err2str(res));
857  goto fail;
858  }
859  }
860 
861  /* enum input */
862  input.index = s->channel;
863  if (v4l2_ioctl(s->fd, VIDIOC_ENUMINPUT, &input) < 0) {
864  res = AVERROR(errno);
865  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_ENUMINPUT): %s\n", av_err2str(res));
866  goto fail;
867  }
868  s->std_id = input.std;
869  av_log(ctx, AV_LOG_DEBUG, "Current input_channel: %d, input_name: %s, input_std: %"PRIx64"\n",
870  s->channel, input.name, (uint64_t)input.std);
871 
872  if (s->list_format) {
873  list_formats(ctx, s->list_format);
874  res = AVERROR_EXIT;
875  goto fail;
876  }
877 
878  if (s->list_standard) {
879  list_standards(ctx);
880  res = AVERROR_EXIT;
881  goto fail;
882  }
883 
884  avpriv_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
885 
886  if (s->pixel_format) {
888 
889  if (codec)
890  ctx->video_codec_id = codec->id;
891 
892  pix_fmt = av_get_pix_fmt(s->pixel_format);
893 
894  if (pix_fmt == AV_PIX_FMT_NONE && !codec) {
895  av_log(ctx, AV_LOG_ERROR, "No such input format: %s.\n",
896  s->pixel_format);
897 
898  res = AVERROR(EINVAL);
899  goto fail;
900  }
901  }
902 
903  if (!s->width && !s->height) {
904  struct v4l2_format fmt = { .type = V4L2_BUF_TYPE_VIDEO_CAPTURE };
905 
906  av_log(ctx, AV_LOG_VERBOSE,
907  "Querying the device for the current frame size\n");
908  if (v4l2_ioctl(s->fd, VIDIOC_G_FMT, &fmt) < 0) {
909  res = AVERROR(errno);
910  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_G_FMT): %s\n",
911  av_err2str(res));
912  goto fail;
913  }
914 
915  s->width = fmt.fmt.pix.width;
916  s->height = fmt.fmt.pix.height;
917  av_log(ctx, AV_LOG_VERBOSE,
918  "Setting frame size to %dx%d\n", s->width, s->height);
919  }
920 
921  res = device_try_init(ctx, pix_fmt, &s->width, &s->height, &desired_format, &codec_id);
922  if (res < 0)
923  goto fail;
924 
925  /* If no pixel_format was specified, the codec_id was not known up
926  * until now. Set video_codec_id in the context, as codec_id will
927  * not be available outside this function
928  */
929  if (codec_id != AV_CODEC_ID_NONE && ctx->video_codec_id == AV_CODEC_ID_NONE)
930  ctx->video_codec_id = codec_id;
931 
932  if ((res = av_image_check_size(s->width, s->height, 0, ctx)) < 0)
933  goto fail;
934 
935  s->pixelformat = desired_format;
936 
937  if ((res = v4l2_set_parameters(ctx)) < 0)
938  goto fail;
939 
940  st->codecpar->format = ff_fmt_v4l2ff(desired_format, codec_id);
941  if (st->codecpar->format != AV_PIX_FMT_NONE)
943  s->width, s->height, 1);
944 
945  if ((res = mmap_init(ctx)) ||
946  (res = mmap_start(ctx)) < 0)
947  goto fail;
948 
950 
952  st->codecpar->codec_id = codec_id;
953  if (codec_id == AV_CODEC_ID_RAWVIDEO)
954  st->codecpar->codec_tag =
956  else if (codec_id == AV_CODEC_ID_H264) {
958  }
959  if (desired_format == V4L2_PIX_FMT_YVU420)
960  st->codecpar->codec_tag = MKTAG('Y', 'V', '1', '2');
961  else if (desired_format == V4L2_PIX_FMT_YVU410)
962  st->codecpar->codec_tag = MKTAG('Y', 'V', 'U', '9');
963  st->codecpar->width = s->width;
964  st->codecpar->height = s->height;
965  if (st->avg_frame_rate.den)
966  st->codecpar->bit_rate = s->frame_size * av_q2d(st->avg_frame_rate) * 8;
967 
968  return 0;
969 
970 fail:
971  v4l2_close(s->fd);
972  return res;
973 }
974 
976 {
977 #if FF_API_CODED_FRAME && FF_API_LAVF_AVCTX
979  struct video_data *s = ctx->priv_data;
980  AVFrame *frame = ctx->streams[0]->codec->coded_frame;
982 #endif
983  int res;
984 
985  if ((res = mmap_read_frame(ctx, pkt)) < 0) {
986  return res;
987  }
988 
989 #if FF_API_CODED_FRAME && FF_API_LAVF_AVCTX
991  if (frame && s->interlaced) {
992  frame->interlaced_frame = 1;
993  frame->top_field_first = s->top_field_first;
994  }
996 #endif
997 
998  return pkt->size;
999 }
1000 
1002 {
1003  struct video_data *s = ctx->priv_data;
1004 
1005  if (atomic_load(&s->buffers_queued) != s->buffers)
1006  av_log(ctx, AV_LOG_WARNING, "Some buffers are still owned by the caller on "
1007  "close.\n");
1008 
1009  mmap_close(s);
1010 
1011  v4l2_close(s->fd);
1012  return 0;
1013 }
1014 
1015 static int v4l2_is_v4l_dev(const char *name)
1016 {
1017  return !strncmp(name, "video", 5) ||
1018  !strncmp(name, "radio", 5) ||
1019  !strncmp(name, "vbi", 3) ||
1020  !strncmp(name, "v4l-subdev", 10);
1021 }
1022 
1024 {
1025  struct video_data *s = ctx->priv_data;
1026  DIR *dir;
1027  struct dirent *entry;
1028  AVDeviceInfo *device = NULL;
1029  struct v4l2_capability cap;
1030  int ret = 0;
1031 
1032  if (!device_list)
1033  return AVERROR(EINVAL);
1034 
1035  dir = opendir("/dev");
1036  if (!dir) {
1037  ret = AVERROR(errno);
1038  av_log(ctx, AV_LOG_ERROR, "Couldn't open the directory: %s\n", av_err2str(ret));
1039  return ret;
1040  }
1041  while ((entry = readdir(dir))) {
1042  if (!v4l2_is_v4l_dev(entry->d_name))
1043  continue;
1044 
1045  snprintf(ctx->filename, sizeof(ctx->filename), "/dev/%s", entry->d_name);
1046  if ((s->fd = device_open(ctx)) < 0)
1047  continue;
1048 
1049  if (v4l2_ioctl(s->fd, VIDIOC_QUERYCAP, &cap) < 0) {
1050  ret = AVERROR(errno);
1051  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYCAP): %s\n", av_err2str(ret));
1052  goto fail;
1053  }
1054 
1055  device = av_mallocz(sizeof(AVDeviceInfo));
1056  if (!device) {
1057  ret = AVERROR(ENOMEM);
1058  goto fail;
1059  }
1060  device->device_name = av_strdup(ctx->filename);
1061  device->device_description = av_strdup(cap.card);
1062  if (!device->device_name || !device->device_description) {
1063  ret = AVERROR(ENOMEM);
1064  goto fail;
1065  }
1066 
1067  if ((ret = av_dynarray_add_nofree(&device_list->devices,
1068  &device_list->nb_devices, device)) < 0)
1069  goto fail;
1070 
1071  v4l2_close(s->fd);
1072  s->fd = -1;
1073  continue;
1074 
1075  fail:
1076  if (device) {
1077  av_freep(&device->device_name);
1078  av_freep(&device->device_description);
1079  av_freep(&device);
1080  }
1081  if (s->fd >= 0)
1082  v4l2_close(s->fd);
1083  s->fd = -1;
1084  break;
1085  }
1086  closedir(dir);
1087  return ret;
1088 }
1089 
1090 #define OFFSET(x) offsetof(struct video_data, x)
1091 #define DEC AV_OPT_FLAG_DECODING_PARAM
1092 
1093 static const AVOption options[] = {
1094  { "standard", "set TV standard, used only by analog frame grabber", OFFSET(standard), AV_OPT_TYPE_STRING, {.str = NULL }, 0, 0, DEC },
1095  { "channel", "set TV channel, used only by frame grabber", OFFSET(channel), AV_OPT_TYPE_INT, {.i64 = -1 }, -1, INT_MAX, DEC },
1096  { "video_size", "set frame size", OFFSET(width), AV_OPT_TYPE_IMAGE_SIZE, {.str = NULL}, 0, 0, DEC },
1097  { "pixel_format", "set preferred pixel format", OFFSET(pixel_format), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
1098  { "input_format", "set preferred pixel format (for raw video) or codec name", OFFSET(pixel_format), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
1099  { "framerate", "set frame rate", OFFSET(framerate), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
1100 
1101  { "list_formats", "list available formats and exit", OFFSET(list_format), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, DEC, "list_formats" },
1102  { "all", "show all available formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.i64 = V4L_ALLFORMATS }, 0, INT_MAX, DEC, "list_formats" },
1103  { "raw", "show only non-compressed formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.i64 = V4L_RAWFORMATS }, 0, INT_MAX, DEC, "list_formats" },
1104  { "compressed", "show only compressed formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.i64 = V4L_COMPFORMATS }, 0, INT_MAX, DEC, "list_formats" },
1105 
1106  { "list_standards", "list supported standards and exit", OFFSET(list_standard), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 1, DEC, "list_standards" },
1107  { "all", "show all supported standards", OFFSET(list_standard), AV_OPT_TYPE_CONST, {.i64 = 1 }, 0, 0, DEC, "list_standards" },
1108 
1109  { "timestamps", "set type of timestamps for grabbed frames", OFFSET(ts_mode), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 2, DEC, "timestamps" },
1110  { "ts", "set type of timestamps for grabbed frames", OFFSET(ts_mode), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 2, DEC, "timestamps" },
1111  { "default", "use timestamps from the kernel", OFFSET(ts_mode), AV_OPT_TYPE_CONST, {.i64 = V4L_TS_DEFAULT }, 0, 2, DEC, "timestamps" },
1112  { "abs", "use absolute timestamps (wall clock)", OFFSET(ts_mode), AV_OPT_TYPE_CONST, {.i64 = V4L_TS_ABS }, 0, 2, DEC, "timestamps" },
1113  { "mono2abs", "force conversion from monotonic to absolute timestamps", OFFSET(ts_mode), AV_OPT_TYPE_CONST, {.i64 = V4L_TS_MONO2ABS }, 0, 2, DEC, "timestamps" },
1114  { "use_libv4l2", "use libv4l2 (v4l-utils) conversion functions", OFFSET(use_libv4l2), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, DEC },
1115  { NULL },
1116 };
1117 
1118 static const AVClass v4l2_class = {
1119  .class_name = "V4L2 indev",
1120  .item_name = av_default_item_name,
1121  .option = options,
1122  .version = LIBAVUTIL_VERSION_INT,
1124 };
1125 
1127  .name = "video4linux2,v4l2",
1128  .long_name = NULL_IF_CONFIG_SMALL("Video4Linux2 device grab"),
1129  .priv_data_size = sizeof(struct video_data),
1130  .read_probe = v4l2_read_probe,
1131  .read_header = v4l2_read_header,
1132  .read_packet = v4l2_read_packet,
1133  .read_close = v4l2_read_close,
1134  .get_device_list = v4l2_get_device_list,
1135  .flags = AVFMT_NOFILE,
1136  .priv_class = &v4l2_class,
1137 };
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
const char * s
Definition: avisynth_c.h:768
#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:187
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:462
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:4601
const char * desc
Definition: nvenc.c:60
#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:4066
int num
Numerator.
Definition: rational.h:59
int size
Definition: avcodec.h:1658
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:222
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:760
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:64
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
AVCodec.
Definition: avcodec.h:3681
const struct fmt_map ff_fmt_conversion_table[]
Definition: v4l2-common.c:21
Format I/O context.
Definition: avformat.h:1349
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:1463
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:4132
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:288
#define v4l2_close
enum AVStreamParseType need_parsing
Definition: avformat.h:1081
static int v4l2_read_header(AVFormatContext *ctx)
Definition: v4l2.c:819
static int mmap_start(AVFormatContext *ctx)
Definition: v4l2.c:592
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4231
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1417
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:1460
uint8_t * data
Definition: avcodec.h:1657
static int v4l2_is_v4l_dev(const char *name)
Definition: v4l2.c:1015
static double av_q2d(AVRational a)
Convert an AVRational to a double.
Definition: rational.h:104
static int flags
Definition: log.c:57
#define AV_LOG_VERBOSE
Detailed information.
Definition: log.h:192
int interlaced_frame
The content of the picture is interlaced.
Definition: frame.h:325
int av_dynarray_add_nofree(void *tab_ptr, int *nb_ptr, void *elem)
Add an element to a dynamic array.
Definition: mem.c:280
#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:642
static int device_open(AVFormatContext *ctx)
Definition: v4l2.c:109
enum AVCodecID video_codec_id
Forced video codec_id.
Definition: avformat.h:1513
#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:4095
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:1023
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
enum AVCodecID id
Definition: avcodec.h:3695
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:429
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition: avcodec.h:214
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#define atomic_load(object)
Definition: stdatomic.h:93
av_default_item_name
#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:179
static const AVOption options[]
Definition: v4l2.c:1093
const char * r
Definition: vf_curves.c:111
#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:4062
AVBufferRef * buf
A reference to the reference-counted buffer where the packet data is stored.
Definition: avcodec.h:1640
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:1090
AVRational avg_frame_rate
Average framerate.
Definition: avformat.h:970
#define FFMAX(a, b)
Definition: common.h:94
#define fail()
Definition: checkasm.h:89
#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:3063
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:281
#define E
Definition: avdct.c:32
char filename[1024]
input or output filename
Definition: avformat.h:1425
#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:625
#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
int n
Definition: avisynth_c.h:684
enum AVCodecID codec_id
Definition: vaapi_decode.c:235
#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 char * avcodec_get_name(enum AVCodecID id)
Get the name of a codec.
Definition: utils.c:3187
int64_t av_gettime(void)
Get the current time in microseconds.
Definition: time.c:39
#define SET_WRAPPERS(prefix)
Stream structure.
Definition: avformat.h:889
#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:237
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:589
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:1001
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:703
#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:461
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:695
full parsing and repack of the first frame only, only implemented for H.264 currently ...
Definition: avformat.h:813
static const AVClass v4l2_class
Definition: v4l2.c:1118
static int v4l2_read_packet(AVFormatContext *ctx, AVPacket *pkt)
Definition: v4l2.c:975
int64_t av_gettime_relative(void)
Get the current time in microseconds since some unspecified starting point.
Definition: time.c:56
AVCodec * avcodec_find_decoder_by_name(const char *name)
Find a registered decoder with the specified name.
Definition: utils.c:3173
int index
Definition: v4l2.c:106
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:473
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:83
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:478
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:94
int den
Denominator.
Definition: rational.h:60
#define av_free(p)
#define FF_ENABLE_DEPRECATION_WARNINGS
Definition: internal.h:84
#define V4L_RAWFORMATS
Definition: v4l2.c:45
int top_field_first
If the content is interlaced, is top field displayed first.
Definition: frame.h:330
void * priv_data
Format private data.
Definition: avformat.h:1377
enum AVPixelFormat ff_fmt_v4l2ff(uint32_t v4l2_fmt, enum AVCodecID codec_id)
Definition: v4l2-common.c:80
AVInputFormat ff_v4l2_demuxer
Definition: v4l2.c:1126
#define DEC
Definition: v4l2.c:1091
#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:664
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
Definition: avformat.h:1252
#define av_malloc_array(a, b)
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: avcodec.h:4070
enum AVPixelFormat av_get_pix_fmt(const char *name)
Return the pixel format corresponding to name.
Definition: pixdesc.c:2261
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:2249
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:812
#define MKTAG(a, b, c, d)
Definition: common.h:342
AVRational r_frame_rate
Real base framerate of the stream.
Definition: avformat.h:1108
int nb_devices
number of autodetected devices
Definition: avdevice.h:462
AVPixelFormat
Pixel format.
Definition: pixfmt.h:60
This structure stores compressed data.
Definition: avcodec.h:1634
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:1650
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