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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 "v4l2-common.h"
34 #include <dirent.h>
35 
36 #if CONFIG_LIBV4L2
37 #include <libv4l2.h>
38 #endif
39 
40 static const int desired_video_buffers = 256;
41 
42 #define V4L_ALLFORMATS 3
43 #define V4L_RAWFORMATS 1
44 #define V4L_COMPFORMATS 2
45 
46 /**
47  * Return timestamps to the user exactly as returned by the kernel
48  */
49 #define V4L_TS_DEFAULT 0
50 /**
51  * Autodetect the kind of timestamps returned by the kernel and convert to
52  * absolute (wall clock) timestamps.
53  */
54 #define V4L_TS_ABS 1
55 /**
56  * Assume kernel timestamps are from the monotonic clock and convert to
57  * absolute timestamps.
58  */
59 #define V4L_TS_MONO2ABS 2
60 
61 /**
62  * Once the kind of timestamps returned by the kernel have been detected,
63  * the value of the timefilter (NULL or not) determines whether a conversion
64  * takes place.
65  */
66 #define V4L_TS_CONVERT_READY V4L_TS_DEFAULT
67 
68 struct video_data {
69  AVClass *class;
70  int fd;
71  int pixelformat; /* V4L2_PIX_FMT_* */
72  int width, height;
76  int ts_mode;
78  int64_t last_time_m;
79 
80  int buffers;
81  volatile int buffers_queued;
82  void **buf_start;
83  unsigned int *buf_len;
84  char *standard;
85  v4l2_std_id std_id;
86  int channel;
87  char *pixel_format; /**< Set by a private option. */
88  int list_format; /**< Set by a private option. */
89  int list_standard; /**< Set by a private option. */
90  char *framerate; /**< Set by a private option. */
91 
93  int (*open_f)(const char *file, int oflag, ...);
94  int (*close_f)(int fd);
95  int (*dup_f)(int fd);
96  int (*ioctl_f)(int fd, unsigned long int request, ...);
97  ssize_t (*read_f)(int fd, void *buffer, size_t n);
98  void *(*mmap_f)(void *start, size_t length, int prot, int flags, int fd, int64_t offset);
99  int (*munmap_f)(void *_start, size_t length);
100 };
101 
102 struct buff_data {
103  struct video_data *s;
104  int index;
105 };
106 
108 {
109  struct video_data *s = ctx->priv_data;
110  struct v4l2_capability cap;
111  int fd;
112  int err;
113  int flags = O_RDWR;
114 
115 #define SET_WRAPPERS(prefix) do { \
116  s->open_f = prefix ## open; \
117  s->close_f = prefix ## close; \
118  s->dup_f = prefix ## dup; \
119  s->ioctl_f = prefix ## ioctl; \
120  s->read_f = prefix ## read; \
121  s->mmap_f = prefix ## mmap; \
122  s->munmap_f = prefix ## munmap; \
123 } while (0)
124 
125  if (s->use_libv4l2) {
126 #if CONFIG_LIBV4L2
127  SET_WRAPPERS(v4l2_);
128 #else
129  av_log(ctx, AV_LOG_ERROR, "libavdevice is not built with libv4l2 support.\n");
130  return AVERROR(EINVAL);
131 #endif
132  } else {
133  SET_WRAPPERS();
134  }
135 
136 #define v4l2_open s->open_f
137 #define v4l2_close s->close_f
138 #define v4l2_dup s->dup_f
139 #define v4l2_ioctl s->ioctl_f
140 #define v4l2_read s->read_f
141 #define v4l2_mmap s->mmap_f
142 #define v4l2_munmap s->munmap_f
143 
144  if (ctx->flags & AVFMT_FLAG_NONBLOCK) {
145  flags |= O_NONBLOCK;
146  }
147 
148  fd = v4l2_open(ctx->filename, flags, 0);
149  if (fd < 0) {
150  err = AVERROR(errno);
151  av_log(ctx, AV_LOG_ERROR, "Cannot open video device %s: %s\n",
152  ctx->filename, av_err2str(err));
153  return err;
154  }
155 
156  if (v4l2_ioctl(fd, VIDIOC_QUERYCAP, &cap) < 0) {
157  err = AVERROR(errno);
158  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYCAP): %s\n",
159  av_err2str(err));
160  goto fail;
161  }
162 
163  av_log(ctx, AV_LOG_VERBOSE, "fd:%d capabilities:%x\n",
164  fd, cap.capabilities);
165 
166  if (!(cap.capabilities & V4L2_CAP_VIDEO_CAPTURE)) {
167  av_log(ctx, AV_LOG_ERROR, "Not a video capture device.\n");
168  err = AVERROR(ENODEV);
169  goto fail;
170  }
171 
172  if (!(cap.capabilities & V4L2_CAP_STREAMING)) {
173  av_log(ctx, AV_LOG_ERROR,
174  "The device does not support the streaming I/O method.\n");
175  err = AVERROR(ENOSYS);
176  goto fail;
177  }
178 
179  return fd;
180 
181 fail:
182  v4l2_close(fd);
183  return err;
184 }
185 
186 static int device_init(AVFormatContext *ctx, int *width, int *height,
187  uint32_t pixelformat)
188 {
189  struct video_data *s = ctx->priv_data;
190  struct v4l2_format fmt = { .type = V4L2_BUF_TYPE_VIDEO_CAPTURE };
191  int res = 0;
192 
193  fmt.fmt.pix.width = *width;
194  fmt.fmt.pix.height = *height;
195  fmt.fmt.pix.pixelformat = pixelformat;
196  fmt.fmt.pix.field = V4L2_FIELD_ANY;
197 
198  /* Some drivers will fail and return EINVAL when the pixelformat
199  is not supported (even if type field is valid and supported) */
200  if (v4l2_ioctl(s->fd, VIDIOC_S_FMT, &fmt) < 0)
201  res = AVERROR(errno);
202 
203  if ((*width != fmt.fmt.pix.width) || (*height != fmt.fmt.pix.height)) {
204  av_log(ctx, AV_LOG_INFO,
205  "The V4L2 driver changed the video from %dx%d to %dx%d\n",
206  *width, *height, fmt.fmt.pix.width, fmt.fmt.pix.height);
207  *width = fmt.fmt.pix.width;
208  *height = fmt.fmt.pix.height;
209  }
210 
211  if (pixelformat != fmt.fmt.pix.pixelformat) {
212  av_log(ctx, AV_LOG_DEBUG,
213  "The V4L2 driver changed the pixel format "
214  "from 0x%08X to 0x%08X\n",
215  pixelformat, fmt.fmt.pix.pixelformat);
216  res = AVERROR(EINVAL);
217  }
218 
219  if (fmt.fmt.pix.field == V4L2_FIELD_INTERLACED) {
220  av_log(ctx, AV_LOG_DEBUG,
221  "The V4L2 driver is using the interlaced mode\n");
222  s->interlaced = 1;
223  }
224 
225  return res;
226 }
227 
228 static int first_field(const struct video_data *s)
229 {
230  int res;
231  v4l2_std_id std;
232 
233  res = v4l2_ioctl(s->fd, VIDIOC_G_STD, &std);
234  if (res < 0)
235  return 0;
236  if (std & V4L2_STD_NTSC)
237  return 0;
238 
239  return 1;
240 }
241 
242 #if HAVE_STRUCT_V4L2_FRMIVALENUM_DISCRETE
243 static void list_framesizes(AVFormatContext *ctx, uint32_t pixelformat)
244 {
245  const struct video_data *s = ctx->priv_data;
246  struct v4l2_frmsizeenum vfse = { .pixel_format = pixelformat };
247 
248  while(!v4l2_ioctl(s->fd, VIDIOC_ENUM_FRAMESIZES, &vfse)) {
249  switch (vfse.type) {
250  case V4L2_FRMSIZE_TYPE_DISCRETE:
251  av_log(ctx, AV_LOG_INFO, " %ux%u",
252  vfse.discrete.width, vfse.discrete.height);
253  break;
254  case V4L2_FRMSIZE_TYPE_CONTINUOUS:
255  case V4L2_FRMSIZE_TYPE_STEPWISE:
256  av_log(ctx, AV_LOG_INFO, " {%u-%u, %u}x{%u-%u, %u}",
257  vfse.stepwise.min_width,
258  vfse.stepwise.max_width,
259  vfse.stepwise.step_width,
260  vfse.stepwise.min_height,
261  vfse.stepwise.max_height,
262  vfse.stepwise.step_height);
263  }
264  vfse.index++;
265  }
266 }
267 #endif
268 
269 static void list_formats(AVFormatContext *ctx, int type)
270 {
271  const struct video_data *s = ctx->priv_data;
272  struct v4l2_fmtdesc vfd = { .type = V4L2_BUF_TYPE_VIDEO_CAPTURE };
273 
274  while(!v4l2_ioctl(s->fd, VIDIOC_ENUM_FMT, &vfd)) {
275  enum AVCodecID codec_id = ff_fmt_v4l2codec(vfd.pixelformat);
276  enum AVPixelFormat pix_fmt = ff_fmt_v4l2ff(vfd.pixelformat, codec_id);
277 
278  vfd.index++;
279 
280  if (!(vfd.flags & V4L2_FMT_FLAG_COMPRESSED) &&
281  type & V4L_RAWFORMATS) {
282  const char *fmt_name = av_get_pix_fmt_name(pix_fmt);
283  av_log(ctx, AV_LOG_INFO, "Raw : %11s : %20s :",
284  fmt_name ? fmt_name : "Unsupported",
285  vfd.description);
286  } else if (vfd.flags & V4L2_FMT_FLAG_COMPRESSED &&
287  type & V4L_COMPFORMATS) {
288  const AVCodecDescriptor *desc = avcodec_descriptor_get(codec_id);
289  av_log(ctx, AV_LOG_INFO, "Compressed: %11s : %20s :",
290  desc ? desc->name : "Unsupported",
291  vfd.description);
292  } else {
293  continue;
294  }
295 
296 #ifdef V4L2_FMT_FLAG_EMULATED
297  if (vfd.flags & V4L2_FMT_FLAG_EMULATED)
298  av_log(ctx, AV_LOG_INFO, " Emulated :");
299 #endif
300 #if HAVE_STRUCT_V4L2_FRMIVALENUM_DISCRETE
301  list_framesizes(ctx, vfd.pixelformat);
302 #endif
303  av_log(ctx, AV_LOG_INFO, "\n");
304  }
305 }
306 
308 {
309  int ret;
310  struct video_data *s = ctx->priv_data;
311  struct v4l2_standard standard;
312 
313  if (s->std_id == 0)
314  return;
315 
316  for (standard.index = 0; ; standard.index++) {
317  if (v4l2_ioctl(s->fd, VIDIOC_ENUMSTD, &standard) < 0) {
318  ret = AVERROR(errno);
319  if (ret == AVERROR(EINVAL)) {
320  break;
321  } else {
322  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_ENUMSTD): %s\n", av_err2str(ret));
323  return;
324  }
325  }
326  av_log(ctx, AV_LOG_INFO, "%2d, %16"PRIx64", %s\n",
327  standard.index, (uint64_t)standard.id, standard.name);
328  }
329 }
330 
331 static int mmap_init(AVFormatContext *ctx)
332 {
333  int i, res;
334  struct video_data *s = ctx->priv_data;
335  struct v4l2_requestbuffers req = {
336  .type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
337  .count = desired_video_buffers,
338  .memory = V4L2_MEMORY_MMAP
339  };
340 
341  if (v4l2_ioctl(s->fd, VIDIOC_REQBUFS, &req) < 0) {
342  res = AVERROR(errno);
343  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_REQBUFS): %s\n", av_err2str(res));
344  return res;
345  }
346 
347  if (req.count < 2) {
348  av_log(ctx, AV_LOG_ERROR, "Insufficient buffer memory\n");
349  return AVERROR(ENOMEM);
350  }
351  s->buffers = req.count;
352  s->buf_start = av_malloc_array(s->buffers, sizeof(void *));
353  if (!s->buf_start) {
354  av_log(ctx, AV_LOG_ERROR, "Cannot allocate buffer pointers\n");
355  return AVERROR(ENOMEM);
356  }
357  s->buf_len = av_malloc_array(s->buffers, sizeof(unsigned int));
358  if (!s->buf_len) {
359  av_log(ctx, AV_LOG_ERROR, "Cannot allocate buffer sizes\n");
360  av_freep(&s->buf_start);
361  return AVERROR(ENOMEM);
362  }
363 
364  for (i = 0; i < req.count; i++) {
365  struct v4l2_buffer buf = {
366  .type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
367  .index = i,
368  .memory = V4L2_MEMORY_MMAP
369  };
370  if (v4l2_ioctl(s->fd, VIDIOC_QUERYBUF, &buf) < 0) {
371  res = AVERROR(errno);
372  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYBUF): %s\n", av_err2str(res));
373  return res;
374  }
375 
376  s->buf_len[i] = buf.length;
377  if (s->frame_size > 0 && s->buf_len[i] < s->frame_size) {
378  av_log(ctx, AV_LOG_ERROR,
379  "buf_len[%d] = %d < expected frame size %d\n",
380  i, s->buf_len[i], s->frame_size);
381  return AVERROR(ENOMEM);
382  }
383  s->buf_start[i] = v4l2_mmap(NULL, buf.length,
384  PROT_READ | PROT_WRITE, MAP_SHARED,
385  s->fd, buf.m.offset);
386 
387  if (s->buf_start[i] == MAP_FAILED) {
388  res = AVERROR(errno);
389  av_log(ctx, AV_LOG_ERROR, "mmap: %s\n", av_err2str(res));
390  return res;
391  }
392  }
393 
394  return 0;
395 }
396 
397 static int enqueue_buffer(struct video_data *s, struct v4l2_buffer *buf)
398 {
399  int res = 0;
400 
401  if (v4l2_ioctl(s->fd, VIDIOC_QBUF, buf) < 0) {
402  res = AVERROR(errno);
403  av_log(NULL, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF): %s\n", av_err2str(res));
404  } else {
406  }
407 
408  return res;
409 }
410 
411 static void mmap_release_buffer(void *opaque, uint8_t *data)
412 {
413  struct v4l2_buffer buf = { 0 };
414  struct buff_data *buf_descriptor = opaque;
415  struct video_data *s = buf_descriptor->s;
416 
417  buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
418  buf.memory = V4L2_MEMORY_MMAP;
419  buf.index = buf_descriptor->index;
420  av_free(buf_descriptor);
421 
422  enqueue_buffer(s, &buf);
423 }
424 
425 #if HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC)
426 static int64_t av_gettime_monotonic(void)
427 {
428  return av_gettime_relative();
429 }
430 #endif
431 
432 static int init_convert_timestamp(AVFormatContext *ctx, int64_t ts)
433 {
434  struct video_data *s = ctx->priv_data;
435  int64_t now;
436 
437  now = av_gettime();
438  if (s->ts_mode == V4L_TS_ABS &&
439  ts <= now + 1 * AV_TIME_BASE && ts >= now - 10 * AV_TIME_BASE) {
440  av_log(ctx, AV_LOG_INFO, "Detected absolute timestamps\n");
442  return 0;
443  }
444 #if HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC)
445  if (ctx->streams[0]->avg_frame_rate.num) {
446  now = av_gettime_monotonic();
447  if (s->ts_mode == V4L_TS_MONO2ABS ||
448  (ts <= now + 1 * AV_TIME_BASE && ts >= now - 10 * AV_TIME_BASE)) {
449  AVRational tb = {AV_TIME_BASE, 1};
450  int64_t period = av_rescale_q(1, tb, ctx->streams[0]->avg_frame_rate);
451  av_log(ctx, AV_LOG_INFO, "Detected monotonic timestamps, converting\n");
452  /* microseconds instead of seconds, MHz instead of Hz */
453  s->timefilter = ff_timefilter_new(1, period, 1.0E-6);
454  if (!s->timefilter)
455  return AVERROR(ENOMEM);
457  return 0;
458  }
459  }
460 #endif
461  av_log(ctx, AV_LOG_ERROR, "Unknown timestamps\n");
462  return AVERROR(EIO);
463 }
464 
465 static int convert_timestamp(AVFormatContext *ctx, int64_t *ts)
466 {
467  struct video_data *s = ctx->priv_data;
468 
469  if (s->ts_mode) {
470  int r = init_convert_timestamp(ctx, *ts);
471  if (r < 0)
472  return r;
473  }
474 #if HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC)
475  if (s->timefilter) {
476  int64_t nowa = av_gettime();
477  int64_t nowm = av_gettime_monotonic();
478  ff_timefilter_update(s->timefilter, nowa, nowm - s->last_time_m);
479  s->last_time_m = nowm;
480  *ts = ff_timefilter_eval(s->timefilter, *ts - nowm);
481  }
482 #endif
483  return 0;
484 }
485 
487 {
488  struct video_data *s = ctx->priv_data;
489  struct v4l2_buffer buf = {
490  .type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
491  .memory = V4L2_MEMORY_MMAP
492  };
493  int res;
494 
495  pkt->size = 0;
496 
497  /* FIXME: Some special treatment might be needed in case of loss of signal... */
498  while ((res = v4l2_ioctl(s->fd, VIDIOC_DQBUF, &buf)) < 0 && (errno == EINTR));
499  if (res < 0) {
500  if (errno == EAGAIN)
501  return AVERROR(EAGAIN);
502 
503  res = AVERROR(errno);
504  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_DQBUF): %s\n",
505  av_err2str(res));
506  return res;
507  }
508 
509  if (buf.index >= s->buffers) {
510  av_log(ctx, AV_LOG_ERROR, "Invalid buffer index received.\n");
511  return AVERROR(EINVAL);
512  }
514  // always keep at least one buffer queued
516 
517 #ifdef V4L2_BUF_FLAG_ERROR
518  if (buf.flags & V4L2_BUF_FLAG_ERROR) {
519  av_log(ctx, AV_LOG_WARNING,
520  "Dequeued v4l2 buffer contains corrupted data (%d bytes).\n",
521  buf.bytesused);
522  buf.bytesused = 0;
523  } else
524 #endif
525  {
526  /* CPIA is a compressed format and we don't know the exact number of bytes
527  * used by a frame, so set it here as the driver announces it. */
528  if (ctx->video_codec_id == AV_CODEC_ID_CPIA)
529  s->frame_size = buf.bytesused;
530 
531  if (s->frame_size > 0 && buf.bytesused != s->frame_size) {
532  av_log(ctx, AV_LOG_ERROR,
533  "Dequeued v4l2 buffer contains %d bytes, but %d were expected. Flags: 0x%08X.\n",
534  buf.bytesused, s->frame_size, buf.flags);
535  enqueue_buffer(s, &buf);
536  return AVERROR_INVALIDDATA;
537  }
538  }
539 
540  /* Image is at s->buff_start[buf.index] */
541  if (avpriv_atomic_int_get(&s->buffers_queued) == FFMAX(s->buffers / 8, 1)) {
542  /* when we start getting low on queued buffers, fall back on copying data */
543  res = av_new_packet(pkt, buf.bytesused);
544  if (res < 0) {
545  av_log(ctx, AV_LOG_ERROR, "Error allocating a packet.\n");
546  enqueue_buffer(s, &buf);
547  return res;
548  }
549  memcpy(pkt->data, s->buf_start[buf.index], buf.bytesused);
550 
551  res = enqueue_buffer(s, &buf);
552  if (res) {
553  av_packet_unref(pkt);
554  return res;
555  }
556  } else {
557  struct buff_data *buf_descriptor;
558 
559  pkt->data = s->buf_start[buf.index];
560  pkt->size = buf.bytesused;
561 
562  buf_descriptor = av_malloc(sizeof(struct buff_data));
563  if (!buf_descriptor) {
564  /* Something went wrong... Since av_malloc() failed, we cannot even
565  * allocate a buffer for memcpying into it
566  */
567  av_log(ctx, AV_LOG_ERROR, "Failed to allocate a buffer descriptor\n");
568  enqueue_buffer(s, &buf);
569 
570  return AVERROR(ENOMEM);
571  }
572  buf_descriptor->index = buf.index;
573  buf_descriptor->s = s;
574 
575  pkt->buf = av_buffer_create(pkt->data, pkt->size, mmap_release_buffer,
576  buf_descriptor, 0);
577  if (!pkt->buf) {
578  av_log(ctx, AV_LOG_ERROR, "Failed to create a buffer\n");
579  enqueue_buffer(s, &buf);
580  av_freep(&buf_descriptor);
581  return AVERROR(ENOMEM);
582  }
583  }
584  pkt->pts = buf.timestamp.tv_sec * INT64_C(1000000) + buf.timestamp.tv_usec;
585  convert_timestamp(ctx, &pkt->pts);
586 
587  return pkt->size;
588 }
589 
590 static int mmap_start(AVFormatContext *ctx)
591 {
592  struct video_data *s = ctx->priv_data;
593  enum v4l2_buf_type type;
594  int i, res;
595 
596  for (i = 0; i < s->buffers; i++) {
597  struct v4l2_buffer buf = {
598  .type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
599  .index = i,
600  .memory = V4L2_MEMORY_MMAP
601  };
602 
603  if (v4l2_ioctl(s->fd, VIDIOC_QBUF, &buf) < 0) {
604  res = AVERROR(errno);
605  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF): %s\n",
606  av_err2str(res));
607  return res;
608  }
609  }
610  s->buffers_queued = s->buffers;
611 
612  type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
613  if (v4l2_ioctl(s->fd, VIDIOC_STREAMON, &type) < 0) {
614  res = AVERROR(errno);
615  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_STREAMON): %s\n",
616  av_err2str(res));
617  return res;
618  }
619 
620  return 0;
621 }
622 
623 static void mmap_close(struct video_data *s)
624 {
625  enum v4l2_buf_type type;
626  int i;
627 
628  type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
629  /* We do not check for the result, because we could
630  * not do anything about it anyway...
631  */
632  v4l2_ioctl(s->fd, VIDIOC_STREAMOFF, &type);
633  for (i = 0; i < s->buffers; i++) {
634  v4l2_munmap(s->buf_start[i], s->buf_len[i]);
635  }
636  av_freep(&s->buf_start);
637  av_freep(&s->buf_len);
638 }
639 
641 {
642  struct video_data *s = ctx->priv_data;
643  struct v4l2_standard standard = { 0 };
644  struct v4l2_streamparm streamparm = { 0 };
645  struct v4l2_fract *tpf;
646  AVRational framerate_q = { 0 };
647  int i, ret;
648 
649  if (s->framerate &&
650  (ret = av_parse_video_rate(&framerate_q, s->framerate)) < 0) {
651  av_log(ctx, AV_LOG_ERROR, "Could not parse framerate '%s'.\n",
652  s->framerate);
653  return ret;
654  }
655 
656  if (s->standard) {
657  if (s->std_id) {
658  ret = 0;
659  av_log(ctx, AV_LOG_DEBUG, "Setting standard: %s\n", s->standard);
660  /* set tv standard */
661  for (i = 0; ; i++) {
662  standard.index = i;
663  if (v4l2_ioctl(s->fd, VIDIOC_ENUMSTD, &standard) < 0) {
664  ret = AVERROR(errno);
665  break;
666  }
667  if (!av_strcasecmp(standard.name, s->standard))
668  break;
669  }
670  if (ret < 0) {
671  av_log(ctx, AV_LOG_ERROR, "Unknown or unsupported standard '%s'\n", s->standard);
672  return ret;
673  }
674 
675  if (v4l2_ioctl(s->fd, VIDIOC_S_STD, &standard.id) < 0) {
676  ret = AVERROR(errno);
677  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_S_STD): %s\n", av_err2str(ret));
678  return ret;
679  }
680  } else {
681  av_log(ctx, AV_LOG_WARNING,
682  "This device does not support any standard\n");
683  }
684  }
685 
686  /* get standard */
687  if (v4l2_ioctl(s->fd, VIDIOC_G_STD, &s->std_id) == 0) {
688  tpf = &standard.frameperiod;
689  for (i = 0; ; i++) {
690  standard.index = i;
691  if (v4l2_ioctl(s->fd, VIDIOC_ENUMSTD, &standard) < 0) {
692  ret = AVERROR(errno);
693  if (ret == AVERROR(EINVAL)
694 #ifdef ENODATA
695  || ret == AVERROR(ENODATA)
696 #endif
697  ) {
698  tpf = &streamparm.parm.capture.timeperframe;
699  break;
700  }
701  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_ENUMSTD): %s\n", av_err2str(ret));
702  return ret;
703  }
704  if (standard.id == s->std_id) {
705  av_log(ctx, AV_LOG_DEBUG,
706  "Current standard: %s, id: %"PRIx64", frameperiod: %d/%d\n",
707  standard.name, (uint64_t)standard.id, tpf->numerator, tpf->denominator);
708  break;
709  }
710  }
711  } else {
712  tpf = &streamparm.parm.capture.timeperframe;
713  }
714 
715  streamparm.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
716  if (v4l2_ioctl(s->fd, VIDIOC_G_PARM, &streamparm) < 0) {
717  ret = AVERROR(errno);
718  av_log(ctx, AV_LOG_WARNING, "ioctl(VIDIOC_G_PARM): %s\n", av_err2str(ret));
719  } else if (framerate_q.num && framerate_q.den) {
720  if (streamparm.parm.capture.capability & V4L2_CAP_TIMEPERFRAME) {
721  tpf = &streamparm.parm.capture.timeperframe;
722 
723  av_log(ctx, AV_LOG_DEBUG, "Setting time per frame to %d/%d\n",
724  framerate_q.den, framerate_q.num);
725  tpf->numerator = framerate_q.den;
726  tpf->denominator = framerate_q.num;
727 
728  if (v4l2_ioctl(s->fd, VIDIOC_S_PARM, &streamparm) < 0) {
729  ret = AVERROR(errno);
730  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_S_PARM): %s\n",
731  av_err2str(ret));
732  return ret;
733  }
734 
735  if (framerate_q.num != tpf->denominator ||
736  framerate_q.den != tpf->numerator) {
737  av_log(ctx, AV_LOG_INFO,
738  "The driver changed the time per frame from "
739  "%d/%d to %d/%d\n",
740  framerate_q.den, framerate_q.num,
741  tpf->numerator, tpf->denominator);
742  }
743  } else {
744  av_log(ctx, AV_LOG_WARNING,
745  "The driver does not permit changing the time per frame\n");
746  }
747  }
748  if (tpf->denominator > 0 && tpf->numerator > 0) {
749  ctx->streams[0]->avg_frame_rate.num = tpf->denominator;
750  ctx->streams[0]->avg_frame_rate.den = tpf->numerator;
751  ctx->streams[0]->r_frame_rate = ctx->streams[0]->avg_frame_rate;
752  } else
753  av_log(ctx, AV_LOG_WARNING, "Time per frame unknown\n");
754 
755  return 0;
756 }
757 
759  enum AVPixelFormat pix_fmt,
760  int *width,
761  int *height,
762  uint32_t *desired_format,
763  enum AVCodecID *codec_id)
764 {
765  int ret, i;
766 
767  *desired_format = ff_fmt_ff2v4l(pix_fmt, ctx->video_codec_id);
768 
769  if (*desired_format) {
770  ret = device_init(ctx, width, height, *desired_format);
771  if (ret < 0) {
772  *desired_format = 0;
773  if (ret != AVERROR(EINVAL))
774  return ret;
775  }
776  }
777 
778  if (!*desired_format) {
779  for (i = 0; ff_fmt_conversion_table[i].codec_id != AV_CODEC_ID_NONE; i++) {
780  if (ctx->video_codec_id == AV_CODEC_ID_NONE ||
782  av_log(ctx, AV_LOG_DEBUG, "Trying to set codec:%s pix_fmt:%s\n",
784  (char *)av_x_if_null(av_get_pix_fmt_name(ff_fmt_conversion_table[i].ff_fmt), "none"));
785 
786  *desired_format = ff_fmt_conversion_table[i].v4l2_fmt;
787  ret = device_init(ctx, width, height, *desired_format);
788  if (ret >= 0)
789  break;
790  else if (ret != AVERROR(EINVAL))
791  return ret;
792  *desired_format = 0;
793  }
794  }
795 
796  if (*desired_format == 0) {
797  av_log(ctx, AV_LOG_ERROR, "Cannot find a proper format for "
798  "codec '%s' (id %d), pixel format '%s' (id %d)\n",
800  (char *)av_x_if_null(av_get_pix_fmt_name(pix_fmt), "none"), pix_fmt);
801  ret = AVERROR(EINVAL);
802  }
803  }
804 
805  *codec_id = ff_fmt_v4l2codec(*desired_format);
806  av_assert0(*codec_id != AV_CODEC_ID_NONE);
807  return ret;
808 }
809 
811 {
812  if (av_strstart(p->filename, "/dev/video", NULL))
813  return AVPROBE_SCORE_MAX - 1;
814  return 0;
815 }
816 
818 {
819  struct video_data *s = ctx->priv_data;
820  AVStream *st;
821  int res = 0;
822  uint32_t desired_format;
825  struct v4l2_input input = { 0 };
826 
827  st = avformat_new_stream(ctx, NULL);
828  if (!st)
829  return AVERROR(ENOMEM);
830 
831 #if CONFIG_LIBV4L2
832  /* silence libv4l2 logging. if fopen() fails v4l2_log_file will be NULL
833  and errors will get sent to stderr */
834  if (s->use_libv4l2)
835  v4l2_log_file = fopen("/dev/null", "w");
836 #endif
837 
838  s->fd = device_open(ctx);
839  if (s->fd < 0)
840  return s->fd;
841 
842  if (s->channel != -1) {
843  /* set video input */
844  av_log(ctx, AV_LOG_DEBUG, "Selecting input_channel: %d\n", s->channel);
845  if (v4l2_ioctl(s->fd, VIDIOC_S_INPUT, &s->channel) < 0) {
846  res = AVERROR(errno);
847  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_S_INPUT): %s\n", av_err2str(res));
848  goto fail;
849  }
850  } else {
851  /* get current video input */
852  if (v4l2_ioctl(s->fd, VIDIOC_G_INPUT, &s->channel) < 0) {
853  res = AVERROR(errno);
854  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_G_INPUT): %s\n", av_err2str(res));
855  goto fail;
856  }
857  }
858 
859  /* enum input */
860  input.index = s->channel;
861  if (v4l2_ioctl(s->fd, VIDIOC_ENUMINPUT, &input) < 0) {
862  res = AVERROR(errno);
863  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_ENUMINPUT): %s\n", av_err2str(res));
864  goto fail;
865  }
866  s->std_id = input.std;
867  av_log(ctx, AV_LOG_DEBUG, "Current input_channel: %d, input_name: %s, input_std: %"PRIx64"\n",
868  s->channel, input.name, (uint64_t)input.std);
869 
870  if (s->list_format) {
871  list_formats(ctx, s->list_format);
872  res = AVERROR_EXIT;
873  goto fail;
874  }
875 
876  if (s->list_standard) {
877  list_standards(ctx);
878  res = AVERROR_EXIT;
879  goto fail;
880  }
881 
882  avpriv_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
883 
884  if (s->pixel_format) {
886 
887  if (codec)
888  ctx->video_codec_id = codec->id;
889 
890  pix_fmt = av_get_pix_fmt(s->pixel_format);
891 
892  if (pix_fmt == AV_PIX_FMT_NONE && !codec) {
893  av_log(ctx, AV_LOG_ERROR, "No such input format: %s.\n",
894  s->pixel_format);
895 
896  res = AVERROR(EINVAL);
897  goto fail;
898  }
899  }
900 
901  if (!s->width && !s->height) {
902  struct v4l2_format fmt = { .type = V4L2_BUF_TYPE_VIDEO_CAPTURE };
903 
904  av_log(ctx, AV_LOG_VERBOSE,
905  "Querying the device for the current frame size\n");
906  if (v4l2_ioctl(s->fd, VIDIOC_G_FMT, &fmt) < 0) {
907  res = AVERROR(errno);
908  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_G_FMT): %s\n",
909  av_err2str(res));
910  goto fail;
911  }
912 
913  s->width = fmt.fmt.pix.width;
914  s->height = fmt.fmt.pix.height;
915  av_log(ctx, AV_LOG_VERBOSE,
916  "Setting frame size to %dx%d\n", s->width, s->height);
917  }
918 
919  res = device_try_init(ctx, pix_fmt, &s->width, &s->height, &desired_format, &codec_id);
920  if (res < 0)
921  goto fail;
922 
923  /* If no pixel_format was specified, the codec_id was not known up
924  * until now. Set video_codec_id in the context, as codec_id will
925  * not be available outside this function
926  */
927  if (codec_id != AV_CODEC_ID_NONE && ctx->video_codec_id == AV_CODEC_ID_NONE)
928  ctx->video_codec_id = codec_id;
929 
930  if ((res = av_image_check_size(s->width, s->height, 0, ctx)) < 0)
931  goto fail;
932 
933  s->pixelformat = desired_format;
934 
935  if ((res = v4l2_set_parameters(ctx)) < 0)
936  goto fail;
937 
938  st->codecpar->format = ff_fmt_v4l2ff(desired_format, codec_id);
940  s->width, s->height, 1);
941 
942  if ((res = mmap_init(ctx)) ||
943  (res = mmap_start(ctx)) < 0)
944  goto fail;
945 
947 
949  st->codecpar->codec_id = codec_id;
950  if (codec_id == AV_CODEC_ID_RAWVIDEO)
951  st->codecpar->codec_tag =
953  else if (codec_id == AV_CODEC_ID_H264) {
955  }
956  if (desired_format == V4L2_PIX_FMT_YVU420)
957  st->codecpar->codec_tag = MKTAG('Y', 'V', '1', '2');
958  else if (desired_format == V4L2_PIX_FMT_YVU410)
959  st->codecpar->codec_tag = MKTAG('Y', 'V', 'U', '9');
960  st->codecpar->width = s->width;
961  st->codecpar->height = s->height;
962  if (st->avg_frame_rate.den)
963  st->codecpar->bit_rate = s->frame_size * av_q2d(st->avg_frame_rate) * 8;
964 
965  return 0;
966 
967 fail:
968  v4l2_close(s->fd);
969  return res;
970 }
971 
973 {
974 #if FF_API_CODED_FRAME && FF_API_LAVF_AVCTX
976  struct video_data *s = ctx->priv_data;
977  AVFrame *frame = ctx->streams[0]->codec->coded_frame;
979 #endif
980  int res;
981 
982  if ((res = mmap_read_frame(ctx, pkt)) < 0) {
983  return res;
984  }
985 
986 #if FF_API_CODED_FRAME && FF_API_LAVF_AVCTX
988  if (frame && s->interlaced) {
989  frame->interlaced_frame = 1;
990  frame->top_field_first = s->top_field_first;
991  }
993 #endif
994 
995  return pkt->size;
996 }
997 
999 {
1000  struct video_data *s = ctx->priv_data;
1001 
1003  av_log(ctx, AV_LOG_WARNING, "Some buffers are still owned by the caller on "
1004  "close.\n");
1005 
1006  mmap_close(s);
1007 
1008  v4l2_close(s->fd);
1009  return 0;
1010 }
1011 
1012 static int v4l2_is_v4l_dev(const char *name)
1013 {
1014  return !strncmp(name, "video", 5) ||
1015  !strncmp(name, "radio", 5) ||
1016  !strncmp(name, "vbi", 3) ||
1017  !strncmp(name, "v4l-subdev", 10);
1018 }
1019 
1021 {
1022  struct video_data *s = ctx->priv_data;
1023  DIR *dir;
1024  struct dirent *entry;
1025  AVDeviceInfo *device = NULL;
1026  struct v4l2_capability cap;
1027  int ret = 0;
1028 
1029  if (!device_list)
1030  return AVERROR(EINVAL);
1031 
1032  dir = opendir("/dev");
1033  if (!dir) {
1034  ret = AVERROR(errno);
1035  av_log(ctx, AV_LOG_ERROR, "Couldn't open the directory: %s\n", av_err2str(ret));
1036  return ret;
1037  }
1038  while ((entry = readdir(dir))) {
1039  if (!v4l2_is_v4l_dev(entry->d_name))
1040  continue;
1041 
1042  snprintf(ctx->filename, sizeof(ctx->filename), "/dev/%s", entry->d_name);
1043  if ((s->fd = device_open(ctx)) < 0)
1044  continue;
1045 
1046  if (v4l2_ioctl(s->fd, VIDIOC_QUERYCAP, &cap) < 0) {
1047  ret = AVERROR(errno);
1048  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYCAP): %s\n", av_err2str(ret));
1049  goto fail;
1050  }
1051 
1052  device = av_mallocz(sizeof(AVDeviceInfo));
1053  if (!device) {
1054  ret = AVERROR(ENOMEM);
1055  goto fail;
1056  }
1057  device->device_name = av_strdup(ctx->filename);
1058  device->device_description = av_strdup(cap.card);
1059  if (!device->device_name || !device->device_description) {
1060  ret = AVERROR(ENOMEM);
1061  goto fail;
1062  }
1063 
1064  if ((ret = av_dynarray_add_nofree(&device_list->devices,
1065  &device_list->nb_devices, device)) < 0)
1066  goto fail;
1067 
1068  v4l2_close(s->fd);
1069  s->fd = -1;
1070  continue;
1071 
1072  fail:
1073  if (device) {
1074  av_freep(&device->device_name);
1075  av_freep(&device->device_description);
1076  av_freep(&device);
1077  }
1078  if (s->fd >= 0)
1079  v4l2_close(s->fd);
1080  s->fd = -1;
1081  break;
1082  }
1083  closedir(dir);
1084  return ret;
1085 }
1086 
1087 #define OFFSET(x) offsetof(struct video_data, x)
1088 #define DEC AV_OPT_FLAG_DECODING_PARAM
1089 
1090 static const AVOption options[] = {
1091  { "standard", "set TV standard, used only by analog frame grabber", OFFSET(standard), AV_OPT_TYPE_STRING, {.str = NULL }, 0, 0, DEC },
1092  { "channel", "set TV channel, used only by frame grabber", OFFSET(channel), AV_OPT_TYPE_INT, {.i64 = -1 }, -1, INT_MAX, DEC },
1093  { "video_size", "set frame size", OFFSET(width), AV_OPT_TYPE_IMAGE_SIZE, {.str = NULL}, 0, 0, DEC },
1094  { "pixel_format", "set preferred pixel format", OFFSET(pixel_format), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
1095  { "input_format", "set preferred pixel format (for raw video) or codec name", OFFSET(pixel_format), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
1096  { "framerate", "set frame rate", OFFSET(framerate), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
1097 
1098  { "list_formats", "list available formats and exit", OFFSET(list_format), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, DEC, "list_formats" },
1099  { "all", "show all available formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.i64 = V4L_ALLFORMATS }, 0, INT_MAX, DEC, "list_formats" },
1100  { "raw", "show only non-compressed formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.i64 = V4L_RAWFORMATS }, 0, INT_MAX, DEC, "list_formats" },
1101  { "compressed", "show only compressed formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.i64 = V4L_COMPFORMATS }, 0, INT_MAX, DEC, "list_formats" },
1102 
1103  { "list_standards", "list supported standards and exit", OFFSET(list_standard), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 1, DEC, "list_standards" },
1104  { "all", "show all supported standards", OFFSET(list_standard), AV_OPT_TYPE_CONST, {.i64 = 1 }, 0, 0, DEC, "list_standards" },
1105 
1106  { "timestamps", "set type of timestamps for grabbed frames", OFFSET(ts_mode), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 2, DEC, "timestamps" },
1107  { "ts", "set type of timestamps for grabbed frames", OFFSET(ts_mode), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 2, DEC, "timestamps" },
1108  { "default", "use timestamps from the kernel", OFFSET(ts_mode), AV_OPT_TYPE_CONST, {.i64 = V4L_TS_DEFAULT }, 0, 2, DEC, "timestamps" },
1109  { "abs", "use absolute timestamps (wall clock)", OFFSET(ts_mode), AV_OPT_TYPE_CONST, {.i64 = V4L_TS_ABS }, 0, 2, DEC, "timestamps" },
1110  { "mono2abs", "force conversion from monotonic to absolute timestamps", OFFSET(ts_mode), AV_OPT_TYPE_CONST, {.i64 = V4L_TS_MONO2ABS }, 0, 2, DEC, "timestamps" },
1111  { "use_libv4l2", "use libv4l2 (v4l-utils) conversion functions", OFFSET(use_libv4l2), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, DEC },
1112  { NULL },
1113 };
1114 
1115 static const AVClass v4l2_class = {
1116  .class_name = "V4L2 indev",
1117  .item_name = av_default_item_name,
1118  .option = options,
1119  .version = LIBAVUTIL_VERSION_INT,
1121 };
1122 
1124  .name = "video4linux2,v4l2",
1125  .long_name = NULL_IF_CONFIG_SMALL("Video4Linux2 device grab"),
1126  .priv_data_size = sizeof(struct video_data),
1127  .read_probe = v4l2_read_probe,
1128  .read_header = v4l2_read_header,
1129  .read_packet = v4l2_read_packet,
1130  .read_close = v4l2_read_close,
1131  .get_device_list = v4l2_get_device_list,
1132  .flags = AVFMT_NOFILE,
1133  .priv_class = &v4l2_class,
1134 };
int(* open_f)(const char *file, int oflag,...)
Definition: v4l2.c:93
#define NULL
Definition: coverity.c:32
Structure describes basic parameters of the device.
Definition: avdevice.h:453
#define avpriv_atomic_int_add_and_fetch
Definition: atomic_gcc.h:50
const char * s
Definition: avisynth_c.h:768
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
#define v4l2_mmap
enum AVCodecID codec_id
Definition: ffmpeg_vaapi.c:149
static enum AVPixelFormat pix_fmt
This structure describes decoded (raw) audio or video data.
Definition: frame.h:190
int frame_size
Definition: v4l2.c:73
int av_parse_video_rate(AVRational *rate, const char *arg)
Parse str and store the detected values in *rate.
Definition: parseutils.c:174
AVOption.
Definition: opt.h:246
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:101
int(* dup_f)(int fd)
Definition: v4l2.c:95
ssize_t(* read_f)(int fd, void *buffer, size_t n)
Definition: v4l2.c:97
char * device_description
human friendly name
Definition: avdevice.h:455
static int device_init(AVFormatContext *ctx, int *width, int *height, uint32_t pixelformat)
Definition: v4l2.c:186
#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:94
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:4581
const char * desc
Definition: nvenc.c:60
#define v4l2_open
char * pixel_format
Set by a private option.
Definition: v4l2.c:87
char * device_name
device name, format depends on device
Definition: avdevice.h:454
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3987
int num
Numerator.
Definition: rational.h:59
int size
Definition: avcodec.h:1608
enum AVCodecID codec_id
Definition: v4l2-common.h:52
static int enqueue_buffer(struct video_data *s, struct v4l2_buffer *buf)
Definition: v4l2.c:397
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:252
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:758
static void list_formats(AVFormatContext *ctx, int type)
Definition: v4l2.c:269
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
unsigned int * buf_len
Definition: v4l2.c:83
AVCodec.
Definition: avcodec.h:3607
const struct fmt_map ff_fmt_conversion_table[]
Definition: v4l2-common.c:21
Format I/O context.
Definition: avformat.h:1338
int channel
Definition: v4l2.c:86
volatile int buffers_queued
Definition: v4l2.c:81
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:1452
v4l2_std_id std_id
Definition: v4l2.c:85
#define V4L_TS_ABS
Autodetect the kind of timestamps returned by the kernel and convert to absolute (wall clock) timesta...
Definition: v4l2.c:54
Opaque type representing a time filter state.
Definition: timefilter.c:30
uint8_t
#define av_malloc(s)
int width
Video only.
Definition: avcodec.h:4053
static int mmap_read_frame(AVFormatContext *ctx, AVPacket *pkt)
Definition: v4l2.c:486
static int init_convert_timestamp(AVFormatContext *ctx, int64_t ts)
Definition: v4l2.c:432
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:1076
static int v4l2_read_header(AVFormatContext *ctx)
Definition: v4l2.c:817
static int mmap_start(AVFormatContext *ctx)
Definition: v4l2.c:590
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4214
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1406
static AVFrame * frame
char * standard
Definition: v4l2.c:84
static const int desired_video_buffers
Definition: v4l2.c:40
#define height
int flags
Flags modifying the (de)muxer behaviour.
Definition: avformat.h:1449
uint8_t * data
Definition: avcodec.h:1607
static int v4l2_is_v4l_dev(const char *name)
Definition: v4l2.c:1012
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:328
int av_dynarray_add_nofree(void *tab_ptr, int *nb_ptr, void *elem)
Add an element to a dynamic array.
Definition: mem.c:310
#define V4L_TS_DEFAULT
Return timestamps to the user exactly as returned by the kernel.
Definition: v4l2.c:49
static int v4l2_set_parameters(AVFormatContext *ctx)
Definition: v4l2.c:640
static int device_open(AVFormatContext *ctx)
Definition: v4l2.c:107
enum AVCodecID video_codec_id
Forced video codec_id.
Definition: avformat.h:1500
#define av_log(a,...)
static int first_field(const struct video_data *s)
Definition: v4l2.c:228
#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:66
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: avcodec.h:4016
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:1020
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:72
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:74
enum AVCodecID id
Definition: avcodec.h:3621
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:361
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition: avcodec.h:191
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
av_default_item_name
#define AVERROR(e)
Definition: error.h:43
#define avpriv_atomic_int_get
Definition: atomic_gcc.h:28
#define v4l2_munmap
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:176
static const AVOption options[]
Definition: v4l2.c:1090
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:3983
AVBufferRef * buf
A reference to the reference-counted buffer where the packet data is stored.
Definition: avcodec.h:1590
void ** buf_start
Definition: v4l2.c:82
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:92
AVDeviceInfo ** devices
list of autodetected devices
Definition: avdevice.h:462
static const uint8_t offset[127][2]
Definition: vf_spp.c:92
#define OFFSET(x)
Definition: v4l2.c:1087
AVRational avg_frame_rate
Average framerate.
Definition: avformat.h:967
#define FFMAX(a, b)
Definition: common.h:94
#define fail()
Definition: checkasm.h:84
#define V4L_TS_MONO2ABS
Assume kernel timestamps are from the monotonic clock and convert to absolute timestamps.
Definition: v4l2.c:59
const AVCodecDescriptor * avcodec_descriptor_get(enum AVCodecID id)
Definition: codec_desc.c:2977
TimeFilter * timefilter
Definition: v4l2.c:77
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:251
#define E
Definition: avdct.c:32
char filename[1024]
input or output filename
Definition: avformat.h:1414
#define AV_TIME_BASE
Internal time base represented as integer.
Definition: avutil.h:254
static void list_standards(AVFormatContext *ctx)
Definition: v4l2.c:307
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:465
static void mmap_close(struct video_data *s)
Definition: v4l2.c:623
#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:76
int n
Definition: avisynth_c.h:684
#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:88
#define v4l2_ioctl
const char * avcodec_get_name(enum AVCodecID id)
Get the name of a codec.
Definition: utils.c:3147
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 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:267
#define V4L_ALLFORMATS
Definition: v4l2.c:42
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:569
void * buf
Definition: avisynth_c.h:690
GLint GLenum type
Definition: opengl_enc.c:105
int fd
Definition: v4l2.c:70
struct video_data * s
Definition: v4l2.c:103
int64_t last_time_m
Definition: v4l2.c:78
Describe the class of an AVClass context structure.
Definition: log.h:67
static int v4l2_read_close(AVFormatContext *ctx)
Definition: v4l2.c:998
Rational number (pair of numerator and denominator).
Definition: rational.h:58
int width
Definition: v4l2.c:72
const char * name
Name of the codec described by this descriptor.
Definition: avcodec.h:668
#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:89
List of devices.
Definition: avdevice.h:461
static int mmap_init(AVFormatContext *ctx)
Definition: v4l2.c:331
This struct describes the properties of a single codec described by an AVCodecID. ...
Definition: avcodec.h:660
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:1115
static int v4l2_read_packet(AVFormatContext *ctx, AVPacket *pkt)
Definition: v4l2.c:972
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:3133
int index
Definition: v4l2.c:104
#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:80
int buffers
Definition: v4l2.c:80
#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:90
#define V4L_COMPFORMATS
Definition: v4l2.c:44
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:81
#define V4L_RAWFORMATS
Definition: v4l2.c:43
int top_field_first
If the content is interlaced, is top field displayed first.
Definition: frame.h:333
void * priv_data
Format private data.
Definition: avformat.h:1366
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:1123
#define DEC
Definition: v4l2.c:1088
#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:53
static void mmap_release_buffer(void *opaque, uint8_t *data)
Definition: v4l2.c:411
AVCodecParameters * codecpar
Definition: avformat.h:1241
#define av_malloc_array(a, b)
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: avcodec.h:3991
enum AVPixelFormat av_get_pix_fmt(const char *name)
Return the pixel format corresponding to name.
Definition: pixdesc.c:2260
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:2248
int pixelformat
Definition: v4l2.c:71
int(* munmap_f)(void *_start, size_t length)
Definition: v4l2.c:99
static int v4l2_read_probe(AVProbeData *p)
Definition: v4l2.c:810
#define MKTAG(a, b, c, d)
Definition: common.h:342
AVRational r_frame_rate
Real base framerate of the stream.
Definition: avformat.h:1103
int nb_devices
number of autodetected devices
Definition: avdevice.h:463
AVPixelFormat
Pixel format.
Definition: pixfmt.h:60
This structure stores compressed data.
Definition: avcodec.h:1584
int(* ioctl_f)(int fd, unsigned long int request,...)
Definition: v4l2.c:96
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1600
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:75