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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 
107 static int device_open(AVFormatContext *ctx)
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 build 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 #if FF_API_DESTRUCT_PACKET
398 static void dummy_release_buffer(AVPacket *pkt)
399 {
400  av_assert0(0);
401 }
402 #endif
403 
404 static int enqueue_buffer(struct video_data *s, struct v4l2_buffer *buf)
405 {
406  int res = 0;
407 
408  if (v4l2_ioctl(s->fd, VIDIOC_QBUF, buf) < 0) {
409  res = AVERROR(errno);
410  av_log(NULL, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF): %s\n", av_err2str(res));
411  } else {
413  }
414 
415  return res;
416 }
417 
418 static void mmap_release_buffer(void *opaque, uint8_t *data)
419 {
420  struct v4l2_buffer buf = { 0 };
421  struct buff_data *buf_descriptor = opaque;
422  struct video_data *s = buf_descriptor->s;
423 
424  buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
425  buf.memory = V4L2_MEMORY_MMAP;
426  buf.index = buf_descriptor->index;
427  av_free(buf_descriptor);
428 
429  enqueue_buffer(s, &buf);
430 }
431 
432 #if HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC)
433 static int64_t av_gettime_monotonic(void)
434 {
435  return av_gettime_relative();
436 }
437 #endif
438 
439 static int init_convert_timestamp(AVFormatContext *ctx, int64_t ts)
440 {
441  struct video_data *s = ctx->priv_data;
442  int64_t now;
443 
444  now = av_gettime();
445  if (s->ts_mode == V4L_TS_ABS &&
446  ts <= now + 1 * AV_TIME_BASE && ts >= now - 10 * AV_TIME_BASE) {
447  av_log(ctx, AV_LOG_INFO, "Detected absolute timestamps\n");
449  return 0;
450  }
451 #if HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC)
452  if (ctx->streams[0]->avg_frame_rate.num) {
453  now = av_gettime_monotonic();
454  if (s->ts_mode == V4L_TS_MONO2ABS ||
455  (ts <= now + 1 * AV_TIME_BASE && ts >= now - 10 * AV_TIME_BASE)) {
456  AVRational tb = {AV_TIME_BASE, 1};
457  int64_t period = av_rescale_q(1, tb, ctx->streams[0]->avg_frame_rate);
458  av_log(ctx, AV_LOG_INFO, "Detected monotonic timestamps, converting\n");
459  /* microseconds instead of seconds, MHz instead of Hz */
460  s->timefilter = ff_timefilter_new(1, period, 1.0E-6);
461  if (!s->timefilter)
462  return AVERROR(ENOMEM);
464  return 0;
465  }
466  }
467 #endif
468  av_log(ctx, AV_LOG_ERROR, "Unknown timestamps\n");
469  return AVERROR(EIO);
470 }
471 
472 static int convert_timestamp(AVFormatContext *ctx, int64_t *ts)
473 {
474  struct video_data *s = ctx->priv_data;
475 
476  if (s->ts_mode) {
477  int r = init_convert_timestamp(ctx, *ts);
478  if (r < 0)
479  return r;
480  }
481 #if HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC)
482  if (s->timefilter) {
483  int64_t nowa = av_gettime();
484  int64_t nowm = av_gettime_monotonic();
485  ff_timefilter_update(s->timefilter, nowa, nowm - s->last_time_m);
486  s->last_time_m = nowm;
487  *ts = ff_timefilter_eval(s->timefilter, *ts - nowm);
488  }
489 #endif
490  return 0;
491 }
492 
494 {
495  struct video_data *s = ctx->priv_data;
496  struct v4l2_buffer buf = {
497  .type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
498  .memory = V4L2_MEMORY_MMAP
499  };
500  int res;
501 
502  pkt->size = 0;
503 
504  /* FIXME: Some special treatment might be needed in case of loss of signal... */
505  while ((res = v4l2_ioctl(s->fd, VIDIOC_DQBUF, &buf)) < 0 && (errno == EINTR));
506  if (res < 0) {
507  if (errno == EAGAIN)
508  return AVERROR(EAGAIN);
509 
510  res = AVERROR(errno);
511  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_DQBUF): %s\n",
512  av_err2str(res));
513  return res;
514  }
515 
516  if (buf.index >= s->buffers) {
517  av_log(ctx, AV_LOG_ERROR, "Invalid buffer index received.\n");
518  return AVERROR(EINVAL);
519  }
521  // always keep at least one buffer queued
523 
524 #ifdef V4L2_BUF_FLAG_ERROR
525  if (buf.flags & V4L2_BUF_FLAG_ERROR) {
526  av_log(ctx, AV_LOG_WARNING,
527  "Dequeued v4l2 buffer contains corrupted data (%d bytes).\n",
528  buf.bytesused);
529  buf.bytesused = 0;
530  } else
531 #endif
532  {
533  /* CPIA is a compressed format and we don't know the exact number of bytes
534  * used by a frame, so set it here as the driver announces it. */
535  if (ctx->video_codec_id == AV_CODEC_ID_CPIA)
536  s->frame_size = buf.bytesused;
537 
538  if (s->frame_size > 0 && buf.bytesused != s->frame_size) {
539  av_log(ctx, AV_LOG_ERROR,
540  "Dequeued v4l2 buffer contains %d bytes, but %d were expected. Flags: 0x%08X.\n",
541  buf.bytesused, s->frame_size, buf.flags);
542  enqueue_buffer(s, &buf);
543  return AVERROR_INVALIDDATA;
544  }
545  }
546 
547  /* Image is at s->buff_start[buf.index] */
548  if (avpriv_atomic_int_get(&s->buffers_queued) == FFMAX(s->buffers / 8, 1)) {
549  /* when we start getting low on queued buffers, fall back on copying data */
550  res = av_new_packet(pkt, buf.bytesused);
551  if (res < 0) {
552  av_log(ctx, AV_LOG_ERROR, "Error allocating a packet.\n");
553  enqueue_buffer(s, &buf);
554  return res;
555  }
556  memcpy(pkt->data, s->buf_start[buf.index], buf.bytesused);
557 
558  res = enqueue_buffer(s, &buf);
559  if (res) {
560  av_free_packet(pkt);
561  return res;
562  }
563  } else {
564  struct buff_data *buf_descriptor;
565 
566  pkt->data = s->buf_start[buf.index];
567  pkt->size = buf.bytesused;
568 #if FF_API_DESTRUCT_PACKET
570  pkt->destruct = dummy_release_buffer;
572 #endif
573 
574  buf_descriptor = av_malloc(sizeof(struct buff_data));
575  if (!buf_descriptor) {
576  /* Something went wrong... Since av_malloc() failed, we cannot even
577  * allocate a buffer for memcpying into it
578  */
579  av_log(ctx, AV_LOG_ERROR, "Failed to allocate a buffer descriptor\n");
580  enqueue_buffer(s, &buf);
581 
582  return AVERROR(ENOMEM);
583  }
584  buf_descriptor->index = buf.index;
585  buf_descriptor->s = s;
586 
587  pkt->buf = av_buffer_create(pkt->data, pkt->size, mmap_release_buffer,
588  buf_descriptor, 0);
589  if (!pkt->buf) {
590  av_log(ctx, AV_LOG_ERROR, "Failed to create a buffer\n");
591  enqueue_buffer(s, &buf);
592  av_freep(&buf_descriptor);
593  return AVERROR(ENOMEM);
594  }
595  }
596  pkt->pts = buf.timestamp.tv_sec * INT64_C(1000000) + buf.timestamp.tv_usec;
597  convert_timestamp(ctx, &pkt->pts);
598 
599  return pkt->size;
600 }
601 
602 static int mmap_start(AVFormatContext *ctx)
603 {
604  struct video_data *s = ctx->priv_data;
605  enum v4l2_buf_type type;
606  int i, res;
607 
608  for (i = 0; i < s->buffers; i++) {
609  struct v4l2_buffer buf = {
610  .type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
611  .index = i,
612  .memory = V4L2_MEMORY_MMAP
613  };
614 
615  if (v4l2_ioctl(s->fd, VIDIOC_QBUF, &buf) < 0) {
616  res = AVERROR(errno);
617  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF): %s\n",
618  av_err2str(res));
619  return res;
620  }
621  }
622  s->buffers_queued = s->buffers;
623 
624  type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
625  if (v4l2_ioctl(s->fd, VIDIOC_STREAMON, &type) < 0) {
626  res = AVERROR(errno);
627  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_STREAMON): %s\n",
628  av_err2str(res));
629  return res;
630  }
631 
632  return 0;
633 }
634 
635 static void mmap_close(struct video_data *s)
636 {
637  enum v4l2_buf_type type;
638  int i;
639 
640  type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
641  /* We do not check for the result, because we could
642  * not do anything about it anyway...
643  */
644  v4l2_ioctl(s->fd, VIDIOC_STREAMOFF, &type);
645  for (i = 0; i < s->buffers; i++) {
646  v4l2_munmap(s->buf_start[i], s->buf_len[i]);
647  }
648  av_freep(&s->buf_start);
649  av_freep(&s->buf_len);
650 }
651 
653 {
654  struct video_data *s = ctx->priv_data;
655  struct v4l2_standard standard = { 0 };
656  struct v4l2_streamparm streamparm = { 0 };
657  struct v4l2_fract *tpf;
658  AVRational framerate_q = { 0 };
659  int i, ret;
660 
661  if (s->framerate &&
662  (ret = av_parse_video_rate(&framerate_q, s->framerate)) < 0) {
663  av_log(ctx, AV_LOG_ERROR, "Could not parse framerate '%s'.\n",
664  s->framerate);
665  return ret;
666  }
667 
668  if (s->standard) {
669  if (s->std_id) {
670  ret = 0;
671  av_log(ctx, AV_LOG_DEBUG, "Setting standard: %s\n", s->standard);
672  /* set tv standard */
673  for (i = 0; ; i++) {
674  standard.index = i;
675  if (v4l2_ioctl(s->fd, VIDIOC_ENUMSTD, &standard) < 0) {
676  ret = AVERROR(errno);
677  break;
678  }
679  if (!av_strcasecmp(standard.name, s->standard))
680  break;
681  }
682  if (ret < 0) {
683  av_log(ctx, AV_LOG_ERROR, "Unknown or unsupported standard '%s'\n", s->standard);
684  return ret;
685  }
686 
687  if (v4l2_ioctl(s->fd, VIDIOC_S_STD, &standard.id) < 0) {
688  ret = AVERROR(errno);
689  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_S_STD): %s\n", av_err2str(ret));
690  return ret;
691  }
692  } else {
693  av_log(ctx, AV_LOG_WARNING,
694  "This device does not support any standard\n");
695  }
696  }
697 
698  /* get standard */
699  if (v4l2_ioctl(s->fd, VIDIOC_G_STD, &s->std_id) == 0) {
700  tpf = &standard.frameperiod;
701  for (i = 0; ; i++) {
702  standard.index = i;
703  if (v4l2_ioctl(s->fd, VIDIOC_ENUMSTD, &standard) < 0) {
704  ret = AVERROR(errno);
705  if (ret == AVERROR(EINVAL)
706 #ifdef ENODATA
707  || ret == AVERROR(ENODATA)
708 #endif
709  ) {
710  tpf = &streamparm.parm.capture.timeperframe;
711  break;
712  }
713  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_ENUMSTD): %s\n", av_err2str(ret));
714  return ret;
715  }
716  if (standard.id == s->std_id) {
717  av_log(ctx, AV_LOG_DEBUG,
718  "Current standard: %s, id: %"PRIx64", frameperiod: %d/%d\n",
719  standard.name, (uint64_t)standard.id, tpf->numerator, tpf->denominator);
720  break;
721  }
722  }
723  } else {
724  tpf = &streamparm.parm.capture.timeperframe;
725  }
726 
727  streamparm.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
728  if (v4l2_ioctl(s->fd, VIDIOC_G_PARM, &streamparm) < 0) {
729  ret = AVERROR(errno);
730  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_G_PARM): %s\n", av_err2str(ret));
731  return ret;
732  }
733 
734  if (framerate_q.num && framerate_q.den) {
735  if (streamparm.parm.capture.capability & V4L2_CAP_TIMEPERFRAME) {
736  tpf = &streamparm.parm.capture.timeperframe;
737 
738  av_log(ctx, AV_LOG_DEBUG, "Setting time per frame to %d/%d\n",
739  framerate_q.den, framerate_q.num);
740  tpf->numerator = framerate_q.den;
741  tpf->denominator = framerate_q.num;
742 
743  if (v4l2_ioctl(s->fd, VIDIOC_S_PARM, &streamparm) < 0) {
744  ret = AVERROR(errno);
745  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_S_PARM): %s\n",
746  av_err2str(ret));
747  return ret;
748  }
749 
750  if (framerate_q.num != tpf->denominator ||
751  framerate_q.den != tpf->numerator) {
752  av_log(ctx, AV_LOG_INFO,
753  "The driver changed the time per frame from "
754  "%d/%d to %d/%d\n",
755  framerate_q.den, framerate_q.num,
756  tpf->numerator, tpf->denominator);
757  }
758  } else {
759  av_log(ctx, AV_LOG_WARNING,
760  "The driver does not permit changing the time per frame\n");
761  }
762  }
763  if (tpf->denominator > 0 && tpf->numerator > 0) {
764  ctx->streams[0]->avg_frame_rate.num = tpf->denominator;
765  ctx->streams[0]->avg_frame_rate.den = tpf->numerator;
766  ctx->streams[0]->r_frame_rate = ctx->streams[0]->avg_frame_rate;
767  } else
768  av_log(ctx, AV_LOG_WARNING, "Time per frame unknown\n");
769 
770  return 0;
771 }
772 
774  enum AVPixelFormat pix_fmt,
775  int *width,
776  int *height,
777  uint32_t *desired_format,
778  enum AVCodecID *codec_id)
779 {
780  int ret, i;
781 
782  *desired_format = ff_fmt_ff2v4l(pix_fmt, ctx->video_codec_id);
783 
784  if (*desired_format) {
785  ret = device_init(ctx, width, height, *desired_format);
786  if (ret < 0) {
787  *desired_format = 0;
788  if (ret != AVERROR(EINVAL))
789  return ret;
790  }
791  }
792 
793  if (!*desired_format) {
794  for (i = 0; ff_fmt_conversion_table[i].codec_id != AV_CODEC_ID_NONE; i++) {
795  if (ctx->video_codec_id == AV_CODEC_ID_NONE ||
797  av_log(ctx, AV_LOG_DEBUG, "Trying to set codec:%s pix_fmt:%s\n",
799  (char *)av_x_if_null(av_get_pix_fmt_name(ff_fmt_conversion_table[i].ff_fmt), "none"));
800 
801  *desired_format = ff_fmt_conversion_table[i].v4l2_fmt;
802  ret = device_init(ctx, width, height, *desired_format);
803  if (ret >= 0)
804  break;
805  else if (ret != AVERROR(EINVAL))
806  return ret;
807  *desired_format = 0;
808  }
809  }
810 
811  if (*desired_format == 0) {
812  av_log(ctx, AV_LOG_ERROR, "Cannot find a proper format for "
813  "codec '%s' (id %d), pixel format '%s' (id %d)\n",
815  (char *)av_x_if_null(av_get_pix_fmt_name(pix_fmt), "none"), pix_fmt);
816  ret = AVERROR(EINVAL);
817  }
818  }
819 
820  *codec_id = ff_fmt_v4l2codec(*desired_format);
821  av_assert0(*codec_id != AV_CODEC_ID_NONE);
822  return ret;
823 }
824 
826 {
827  if (av_strstart(p->filename, "/dev/video", NULL))
828  return AVPROBE_SCORE_MAX - 1;
829  return 0;
830 }
831 
833 {
834  struct video_data *s = ctx->priv_data;
835  AVStream *st;
836  int res = 0;
837  uint32_t desired_format;
840  struct v4l2_input input = { 0 };
841 
842  st = avformat_new_stream(ctx, NULL);
843  if (!st)
844  return AVERROR(ENOMEM);
845 
846 #if CONFIG_LIBV4L2
847  /* silence libv4l2 logging. if fopen() fails v4l2_log_file will be NULL
848  and errors will get sent to stderr */
849  if (s->use_libv4l2)
850  v4l2_log_file = fopen("/dev/null", "w");
851 #endif
852 
853  s->fd = device_open(ctx);
854  if (s->fd < 0)
855  return s->fd;
856 
857  if (s->channel != -1) {
858  /* set video input */
859  av_log(ctx, AV_LOG_DEBUG, "Selecting input_channel: %d\n", s->channel);
860  if (v4l2_ioctl(s->fd, VIDIOC_S_INPUT, &s->channel) < 0) {
861  res = AVERROR(errno);
862  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_S_INPUT): %s\n", av_err2str(res));
863  goto fail;
864  }
865  } else {
866  /* get current video input */
867  if (v4l2_ioctl(s->fd, VIDIOC_G_INPUT, &s->channel) < 0) {
868  res = AVERROR(errno);
869  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_G_INPUT): %s\n", av_err2str(res));
870  goto fail;
871  }
872  }
873 
874  /* enum input */
875  input.index = s->channel;
876  if (v4l2_ioctl(s->fd, VIDIOC_ENUMINPUT, &input) < 0) {
877  res = AVERROR(errno);
878  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_ENUMINPUT): %s\n", av_err2str(res));
879  goto fail;
880  }
881  s->std_id = input.std;
882  av_log(ctx, AV_LOG_DEBUG, "Current input_channel: %d, input_name: %s, input_std: %"PRIx64"\n",
883  s->channel, input.name, (uint64_t)input.std);
884 
885  if (s->list_format) {
886  list_formats(ctx, s->list_format);
887  res = AVERROR_EXIT;
888  goto fail;
889  }
890 
891  if (s->list_standard) {
892  list_standards(ctx);
893  res = AVERROR_EXIT;
894  goto fail;
895  }
896 
897  avpriv_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
898 
899  if (s->pixel_format) {
901 
902  if (codec)
903  ctx->video_codec_id = codec->id;
904 
905  pix_fmt = av_get_pix_fmt(s->pixel_format);
906 
907  if (pix_fmt == AV_PIX_FMT_NONE && !codec) {
908  av_log(ctx, AV_LOG_ERROR, "No such input format: %s.\n",
909  s->pixel_format);
910 
911  res = AVERROR(EINVAL);
912  goto fail;
913  }
914  }
915 
916  if (!s->width && !s->height) {
917  struct v4l2_format fmt = { .type = V4L2_BUF_TYPE_VIDEO_CAPTURE };
918 
919  av_log(ctx, AV_LOG_VERBOSE,
920  "Querying the device for the current frame size\n");
921  if (v4l2_ioctl(s->fd, VIDIOC_G_FMT, &fmt) < 0) {
922  res = AVERROR(errno);
923  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_G_FMT): %s\n",
924  av_err2str(res));
925  goto fail;
926  }
927 
928  s->width = fmt.fmt.pix.width;
929  s->height = fmt.fmt.pix.height;
930  av_log(ctx, AV_LOG_VERBOSE,
931  "Setting frame size to %dx%d\n", s->width, s->height);
932  }
933 
934  res = device_try_init(ctx, pix_fmt, &s->width, &s->height, &desired_format, &codec_id);
935  if (res < 0)
936  goto fail;
937 
938  /* If no pixel_format was specified, the codec_id was not known up
939  * until now. Set video_codec_id in the context, as codec_id will
940  * not be available outside this function
941  */
942  if (codec_id != AV_CODEC_ID_NONE && ctx->video_codec_id == AV_CODEC_ID_NONE)
943  ctx->video_codec_id = codec_id;
944 
945  if ((res = av_image_check_size(s->width, s->height, 0, ctx)) < 0)
946  goto fail;
947 
948  s->pixelformat = desired_format;
949 
950  if ((res = v4l2_set_parameters(ctx)) < 0)
951  goto fail;
952 
953  st->codec->pix_fmt = ff_fmt_v4l2ff(desired_format, codec_id);
954  s->frame_size =
956 
957  if ((res = mmap_init(ctx)) ||
958  (res = mmap_start(ctx)) < 0)
959  goto fail;
960 
962 
964  st->codec->codec_id = codec_id;
965  if (codec_id == AV_CODEC_ID_RAWVIDEO)
966  st->codec->codec_tag =
968  else if (codec_id == AV_CODEC_ID_H264) {
970  }
971  if (desired_format == V4L2_PIX_FMT_YVU420)
972  st->codec->codec_tag = MKTAG('Y', 'V', '1', '2');
973  else if (desired_format == V4L2_PIX_FMT_YVU410)
974  st->codec->codec_tag = MKTAG('Y', 'V', 'U', '9');
975  st->codec->width = s->width;
976  st->codec->height = s->height;
977  if (st->avg_frame_rate.den)
978  st->codec->bit_rate = s->frame_size * av_q2d(st->avg_frame_rate) * 8;
979 
980  return 0;
981 
982 fail:
983  v4l2_close(s->fd);
984  return res;
985 }
986 
988 {
989  struct video_data *s = ctx->priv_data;
990 #if FF_API_CODED_FRAME
992  AVFrame *frame = ctx->streams[0]->codec->coded_frame;
994 #endif
995  int res;
996 
997  av_init_packet(pkt);
998  if ((res = mmap_read_frame(ctx, pkt)) < 0) {
999  return res;
1000  }
1001 
1002 #if FF_API_CODED_FRAME
1004  if (frame && s->interlaced) {
1005  frame->interlaced_frame = 1;
1006  frame->top_field_first = s->top_field_first;
1007  }
1009 #endif
1010 
1011  return pkt->size;
1012 }
1013 
1015 {
1016  struct video_data *s = ctx->priv_data;
1017 
1019  av_log(ctx, AV_LOG_WARNING, "Some buffers are still owned by the caller on "
1020  "close.\n");
1021 
1022  mmap_close(s);
1023 
1024  v4l2_close(s->fd);
1025  return 0;
1026 }
1027 
1028 static int v4l2_is_v4l_dev(const char *name)
1029 {
1030  return !strncmp(name, "video", 5) ||
1031  !strncmp(name, "radio", 5) ||
1032  !strncmp(name, "vbi", 3) ||
1033  !strncmp(name, "v4l-subdev", 10);
1034 }
1035 
1037 {
1038  struct video_data *s = ctx->priv_data;
1039  DIR *dir;
1040  struct dirent *entry;
1041  AVDeviceInfo *device = NULL;
1042  struct v4l2_capability cap;
1043  int ret = 0;
1044 
1045  if (!device_list)
1046  return AVERROR(EINVAL);
1047 
1048  dir = opendir("/dev");
1049  if (!dir) {
1050  ret = AVERROR(errno);
1051  av_log(ctx, AV_LOG_ERROR, "Couldn't open the directory: %s\n", av_err2str(ret));
1052  return ret;
1053  }
1054  while ((entry = readdir(dir))) {
1055  if (!v4l2_is_v4l_dev(entry->d_name))
1056  continue;
1057 
1058  snprintf(ctx->filename, sizeof(ctx->filename), "/dev/%s", entry->d_name);
1059  if ((s->fd = device_open(ctx)) < 0)
1060  continue;
1061 
1062  if (v4l2_ioctl(s->fd, VIDIOC_QUERYCAP, &cap) < 0) {
1063  ret = AVERROR(errno);
1064  av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYCAP): %s\n", av_err2str(ret));
1065  goto fail;
1066  }
1067 
1068  device = av_mallocz(sizeof(AVDeviceInfo));
1069  if (!device) {
1070  ret = AVERROR(ENOMEM);
1071  goto fail;
1072  }
1073  device->device_name = av_strdup(ctx->filename);
1074  device->device_description = av_strdup(cap.card);
1075  if (!device->device_name || !device->device_description) {
1076  ret = AVERROR(ENOMEM);
1077  goto fail;
1078  }
1079 
1080  if ((ret = av_dynarray_add_nofree(&device_list->devices,
1081  &device_list->nb_devices, device)) < 0)
1082  goto fail;
1083 
1084  v4l2_close(s->fd);
1085  s->fd = -1;
1086  continue;
1087 
1088  fail:
1089  if (device) {
1090  av_freep(&device->device_name);
1091  av_freep(&device->device_description);
1092  av_freep(&device);
1093  }
1094  if (s->fd >= 0)
1095  v4l2_close(s->fd);
1096  s->fd = -1;
1097  break;
1098  }
1099  closedir(dir);
1100  return ret;
1101 }
1102 
1103 #define OFFSET(x) offsetof(struct video_data, x)
1104 #define DEC AV_OPT_FLAG_DECODING_PARAM
1105 
1106 static const AVOption options[] = {
1107  { "standard", "set TV standard, used only by analog frame grabber", OFFSET(standard), AV_OPT_TYPE_STRING, {.str = NULL }, 0, 0, DEC },
1108  { "channel", "set TV channel, used only by frame grabber", OFFSET(channel), AV_OPT_TYPE_INT, {.i64 = -1 }, -1, INT_MAX, DEC },
1109  { "video_size", "set frame size", OFFSET(width), AV_OPT_TYPE_IMAGE_SIZE, {.str = NULL}, 0, 0, DEC },
1110  { "pixel_format", "set preferred pixel format", OFFSET(pixel_format), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
1111  { "input_format", "set preferred pixel format (for raw video) or codec name", OFFSET(pixel_format), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
1112  { "framerate", "set frame rate", OFFSET(framerate), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
1113 
1114  { "list_formats", "list available formats and exit", OFFSET(list_format), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, DEC, "list_formats" },
1115  { "all", "show all available formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.i64 = V4L_ALLFORMATS }, 0, INT_MAX, DEC, "list_formats" },
1116  { "raw", "show only non-compressed formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.i64 = V4L_RAWFORMATS }, 0, INT_MAX, DEC, "list_formats" },
1117  { "compressed", "show only compressed formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.i64 = V4L_COMPFORMATS }, 0, INT_MAX, DEC, "list_formats" },
1118 
1119  { "list_standards", "list supported standards and exit", OFFSET(list_standard), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 1, DEC, "list_standards" },
1120  { "all", "show all supported standards", OFFSET(list_standard), AV_OPT_TYPE_CONST, {.i64 = 1 }, 0, 0, DEC, "list_standards" },
1121 
1122  { "timestamps", "set type of timestamps for grabbed frames", OFFSET(ts_mode), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 2, DEC, "timestamps" },
1123  { "ts", "set type of timestamps for grabbed frames", OFFSET(ts_mode), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 2, DEC, "timestamps" },
1124  { "default", "use timestamps from the kernel", OFFSET(ts_mode), AV_OPT_TYPE_CONST, {.i64 = V4L_TS_DEFAULT }, 0, 2, DEC, "timestamps" },
1125  { "abs", "use absolute timestamps (wall clock)", OFFSET(ts_mode), AV_OPT_TYPE_CONST, {.i64 = V4L_TS_ABS }, 0, 2, DEC, "timestamps" },
1126  { "mono2abs", "force conversion from monotonic to absolute timestamps", OFFSET(ts_mode), AV_OPT_TYPE_CONST, {.i64 = V4L_TS_MONO2ABS }, 0, 2, DEC, "timestamps" },
1127  { "use_libv4l2", "use libv4l2 (v4l-utils) conversion functions", OFFSET(use_libv4l2), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 1, DEC },
1128  { NULL },
1129 };
1130 
1131 static const AVClass v4l2_class = {
1132  .class_name = "V4L2 indev",
1133  .item_name = av_default_item_name,
1134  .option = options,
1135  .version = LIBAVUTIL_VERSION_INT,
1137 };
1138 
1140  .name = "video4linux2,v4l2",
1141  .long_name = NULL_IF_CONFIG_SMALL("Video4Linux2 device grab"),
1142  .priv_data_size = sizeof(struct video_data),
1143  .read_probe = v4l2_read_probe,
1144  .read_header = v4l2_read_header,
1145  .read_packet = v4l2_read_packet,
1146  .read_close = v4l2_read_close,
1147  .get_device_list = v4l2_get_device_list,
1148  .flags = AVFMT_NOFILE,
1149  .priv_class = &v4l2_class,
1150 };
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:451
#define avpriv_atomic_int_add_and_fetch
Definition: atomic_gcc.h:50
const char * s
Definition: avisynth_c.h:631
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
#define v4l2_mmap
static enum AVPixelFormat pix_fmt
void av_free_packet(AVPacket *pkt)
Free a packet.
Definition: avpacket.c:280
This structure describes decoded (raw) audio or video data.
Definition: frame.h:171
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:173
AVOption.
Definition: opt.h:255
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:453
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:62
const char * filename
Definition: avformat.h:449
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:4075
#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:452
int num
numerator
Definition: rational.h:44
int size
Definition: avcodec.h:1423
enum AVCodecID codec_id
Definition: v4l2-common.h:52
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1721
static int enqueue_buffer(struct video_data *s, struct v4l2_buffer *buf)
Definition: v4l2.c:404
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:773
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:3471
const struct fmt_map ff_fmt_conversion_table[]
Definition: v4l2-common.c:21
Format I/O context.
Definition: avformat.h:1273
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:1387
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)
static int mmap_read_frame(AVFormatContext *ctx, AVPacket *pkt)
Definition: v4l2.c:493
static int init_convert_timestamp(AVFormatContext *ctx, int64_t ts)
Definition: v4l2.c:439
attribute_deprecated void(* destruct)(struct AVPacket *)
Definition: avcodec.h:1443
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:232
#define v4l2_close
enum AVStreamParseType need_parsing
Definition: avformat.h:1034
int av_dynarray_add_nofree(void *tab_ptr, int *nb_ptr, void *elem)
Add an element to a dynamic array.
Definition: mem.c:310
static int v4l2_read_header(AVFormatContext *ctx)
Definition: v4l2.c:832
static int mmap_start(AVFormatContext *ctx)
Definition: v4l2.c:602
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:3741
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1341
static AVFrame * frame
char * standard
Definition: v4l2.c:84
static const int desired_video_buffers
Definition: v4l2.c:40
static double av_q2d(AVRational a)
Convert rational to double.
Definition: rational.h:80
int flags
Flags modifying the (de)muxer behaviour.
Definition: avformat.h:1384
uint8_t * data
Definition: avcodec.h:1422
static int v4l2_is_v4l_dev(const char *name)
Definition: v4l2.c:1028
#define AV_LOG_VERBOSE
Detailed information.
Definition: log.h:192
#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:652
static int device_open(AVFormatContext *ctx)
Definition: v4l2.c:107
enum AVCodecID video_codec_id
Forced video codec_id.
Definition: avformat.h:1429
#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
static void * av_x_if_null(const void *p, const void *x)
Return x default pointer in case p is NULL.
Definition: avutil.h:300
static int v4l2_get_device_list(AVFormatContext *ctx, AVDeviceInfoList *device_list)
Definition: v4l2.c:1036
int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq)
Rescale a 64-bit integer by 2 rational numbers.
Definition: mathematics.c:140
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:83
int interlaced
Definition: v4l2.c:74
enum AVCodecID id
Definition: avcodec.h:3485
AVCodecID
Identify the syntax and semantics of the bitstream.
Definition: avcodec.h:102
#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:175
static const AVOption options[]
Definition: v4l2.c:1106
const char * r
Definition: vf_curves.c:107
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:197
AVBufferRef * buf
A reference to the reference-counted buffer where the packet data is stored.
Definition: avcodec.h:1405
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
enum AVCodecID codec_id
Definition: mov_chan.c:433
AVDeviceInfo ** devices
list of autodetected devices
Definition: avdevice.h:460
static const uint8_t offset[127][2]
Definition: vf_spp.c:92
#define OFFSET(x)
Definition: v4l2.c:1103
AVRational avg_frame_rate
Average framerate.
Definition: avformat.h:925
#define FFMAX(a, b)
Definition: common.h:64
#define fail()
Definition: checkasm.h:57
#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:2928
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:861
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:241
int bit_rate
the average bitrate
Definition: avcodec.h:1566
#define E
Definition: avdct.c:32
char filename[1024]
input or output filename
Definition: avformat.h:1349
#define AV_TIME_BASE
Internal time base represented as integer.
Definition: avutil.h:246
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
int width
picture width / height.
Definition: avcodec.h:1680
static int convert_timestamp(AVFormatContext *ctx, int64_t *ts)
Definition: v4l2.c:472
static void mmap_close(struct video_data *s)
Definition: v4l2.c:635
#define av_err2str(errnum)
Convenience macro, the return value should be used only directly in function arguments but never stan...
Definition: error.h:119
int ts_mode
Definition: v4l2.c:76
int n
Definition: avisynth_c.h:547
#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:3035
int64_t av_gettime(void)
Get the current time in microseconds.
Definition: time.c:39
#define SET_WRAPPERS(prefix)
Stream structure.
Definition: avformat.h:842
#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
enum AVMediaType codec_type
Definition: avcodec.h:1509
#define V4L_ALLFORMATS
Definition: v4l2.c:42
enum AVCodecID codec_id
Definition: avcodec.h:1518
char * av_strdup(const char *s)
Duplicate the string s.
Definition: mem.c:267
unsigned int codec_tag
fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
Definition: avcodec.h:1533
void * buf
Definition: avisynth_c.h:553
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
BYTE int const BYTE int int int height
Definition: avisynth_c.h:676
Describe the class of an AVClass context structure.
Definition: log.h:67
static int v4l2_read_close(AVFormatContext *ctx)
Definition: v4l2.c:1014
rational number numerator/denominator
Definition: rational.h:43
int width
Definition: v4l2.c:72
const char * name
Name of the codec described by this descriptor.
Definition: avcodec.h:573
#define snprintf
Definition: snprintf.h:34
offset must point to two consecutive integers
Definition: opt.h:232
This structure contains the data a format has to probe a file.
Definition: avformat.h:448
int list_standard
Set by a private option.
Definition: v4l2.c:89
List of devices.
Definition: avdevice.h:459
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:565
full parsing and repack of the first frame only, only implemented for H.264 currently ...
Definition: avformat.h:777
static const AVClass v4l2_class
Definition: v4l2.c:1131
static int v4l2_read_packet(AVFormatContext *ctx, AVPacket *pkt)
Definition: v4l2.c:987
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:3021
static int flags
Definition: cpu.c:47
int index
Definition: v4l2.c:104
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:460
int av_strstart(const char *str, const char *pfx, const char **ptr)
Return non-zero if pfx is a prefix of str.
Definition: avstring.c:34
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:79
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:465
char * framerate
Set by a private option.
Definition: v4l2.c:90
#define V4L_COMPFORMATS
Definition: v4l2.c:44
attribute_deprecated AVFrame * coded_frame
the picture in the bitstream
Definition: avcodec.h:3023
void av_init_packet(AVPacket *pkt)
Initialize optional fields of a packet with default values.
Definition: avpacket.c:49
enum AVCodecID ff_fmt_v4l2codec(uint32_t v4l2_fmt)
Definition: v4l2-common.c:94
int den
denominator
Definition: rational.h:45
#define av_free(p)
#define FF_ENABLE_DEPRECATION_WARNINGS
Definition: internal.h:80
#define V4L_RAWFORMATS
Definition: v4l2.c:43
void * priv_data
Format private data.
Definition: avformat.h:1301
int avpicture_get_size(enum AVPixelFormat pix_fmt, int width, int height)
Calculate the size in bytes that a picture of the given width and height would occupy if stored in th...
Definition: avpicture.c:49
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:1139
#define DEC
Definition: v4l2.c:1104
#define av_freep(p)
void INT64 start
Definition: avisynth_c.h:553
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:628
uint32_t v4l2_fmt
Definition: v4l2-common.h:53
static void mmap_release_buffer(void *opaque, uint8_t *data)
Definition: v4l2.c:418
#define av_malloc_array(a, b)
enum AVPixelFormat av_get_pix_fmt(const char *name)
Return the pixel format corresponding to name.
Definition: pixdesc.c:2062
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:2050
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:825
#define MKTAG(a, b, c, d)
Definition: common.h:315
AVRational r_frame_rate
Real base framerate of the stream.
Definition: avformat.h:1061
int nb_devices
number of autodetected devices
Definition: avdevice.h:461
AVPixelFormat
Pixel format.
Definition: pixfmt.h:61
This structure stores compressed data.
Definition: avcodec.h:1399
void * av_mallocz(size_t size)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:252
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:1415
GLuint buffer
Definition: opengl_enc.c:102
#define tb
Definition: regdef.h:68
const char * name
Definition: opengl_enc.c:103
static int width
int top_field_first
Definition: v4l2.c:75