FFmpeg coverage

Line	Branch	Exec	Source
1			/*
2			* Copyright (c) 2000,2001 Fabrice Bellard
3			* Copyright (c) 2006 Luca Abeni
4			*
5			* This file is part of FFmpeg.
6			*
7			* FFmpeg is free software; you can redistribute it and/or
8			* modify it under the terms of the GNU Lesser General Public
9			* License as published by the Free Software Foundation; either
10			* version 2.1 of the License, or (at your option) any later version.
11			*
12			* FFmpeg is distributed in the hope that it will be useful,
13			* but WITHOUT ANY WARRANTY; without even the implied warranty of
14			* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15			* Lesser General Public License for more details.
16			*
17			* You should have received a copy of the GNU Lesser General Public
18			* License along with FFmpeg; if not, write to the Free Software
19			* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20			*/
21
22			/**
23			* @file
24			* Video4Linux2 grab interface
25			*
26			* Part of this file is based on the V4L2 video capture example
27			* (http://linuxtv.org/downloads/v4l-dvb-apis/capture-example.html)
28			*
29			* Thanks to Michael Niedermayer for providing the mapping between
30			* V4L2_PIX_FMT_* and AV_PIX_FMT_*
31			*/
32
33			#include <stdatomic.h>
34
35			#include "libavutil/avassert.h"
36			#include "libavutil/avstring.h"
37			#include "libavutil/imgutils.h"
38			#include "libavutil/mem.h"
39			#include "libavutil/parseutils.h"
40			#include "libavutil/pixdesc.h"
41			#include "libavutil/time.h"
42			#include "libavcodec/avcodec.h"
43			#include "libavcodec/codec_desc.h"
44			#include "libavformat/demux.h"
45			#include "libavformat/internal.h"
46			#include "avdevice.h"
47			#include "timefilter.h"
48			#include "v4l2-common.h"
49			#include <dirent.h>
50
51			#if CONFIG_LIBV4L2
52			#include <libv4l2.h>
53			#endif
54
55			static const int desired_video_buffers = 256;
56
57			#define V4L_ALLFORMATS 3
58			#define V4L_RAWFORMATS 1
59			#define V4L_COMPFORMATS 2
60
61			/**
62			* Return timestamps to the user exactly as returned by the kernel
63			*/
64			#define V4L_TS_DEFAULT 0
65			/**
66			* Autodetect the kind of timestamps returned by the kernel and convert to
67			* absolute (wall clock) timestamps.
68			*/
69			#define V4L_TS_ABS 1
70			/**
71			* Assume kernel timestamps are from the monotonic clock and convert to
72			* absolute timestamps.
73			*/
74			#define V4L_TS_MONO2ABS 2
75
76			/**
77			* Once the kind of timestamps returned by the kernel have been detected,
78			* the value of the timefilter (NULL or not) determines whether a conversion
79			* takes place.
80			*/
81			#define V4L_TS_CONVERT_READY V4L_TS_DEFAULT
82
83			struct video_data {
84			AVClass *class;
85			int fd;
86			int pixelformat; /* V4L2_PIX_FMT_* */
87			int width, height;
88			int frame_size;
89			int interlaced;
90			int top_field_first;
91			int ts_mode;
92			TimeFilter *timefilter;
93			int64_t last_time_m;
94
95			int buffers;
96			atomic_int buffers_queued;
97			void **buf_start;
98			unsigned int *buf_len;
99			char *standard;
100			v4l2_std_id std_id;
101			int channel;
102			char *pixel_format; /**< Set by a private option. */
103			int list_format; /**< Set by a private option. */
104			int list_standard; /**< Set by a private option. */
105			char *framerate; /**< Set by a private option. */
106
107			int use_libv4l2;
108			int (*open_f)(const char *file, int oflag, ...);
109			int (*close_f)(int fd);
110			int (*dup_f)(int fd);
111			#ifdef __GLIBC__
112			int (*ioctl_f)(int fd, unsigned long int request, ...);
113			#else
114			int (*ioctl_f)(int fd, int request, ...);
115			#endif
116			ssize_t (*read_f)(int fd, void *buffer, size_t n);
117			void *(*mmap_f)(void *start, size_t length, int prot, int flags, int fd, int64_t offset);
118			int (*munmap_f)(void *_start, size_t length);
119			};
120
121			struct buff_data {
122			struct video_data *s;
123			int index;
124			};
125
126		✗	static int device_open(AVFormatContext *ctx, const char* device_path)
127			{
128		✗	struct video_data *s = ctx->priv_data;
129			struct v4l2_capability cap;
130			int fd;
131			int err;
132		✗	int flags = O_RDWR;
133
134			#define SET_WRAPPERS(prefix) do { \
135			s->open_f = prefix ## open; \
136			s->close_f = prefix ## close; \
137			s->dup_f = prefix ## dup; \
138			s->ioctl_f = prefix ## ioctl; \
139			s->read_f = prefix ## read; \
140			s->mmap_f = prefix ## mmap; \
141			s->munmap_f = prefix ## munmap; \
142			} while (0)
143
144		✗	if (s->use_libv4l2) {
145			#if CONFIG_LIBV4L2
146			SET_WRAPPERS(v4l2_);
147			#else
148		✗	av_log(ctx, AV_LOG_ERROR, "libavdevice is not built with libv4l2 support.\n");
149		✗	return AVERROR(EINVAL);
150			#endif
151			} else {
152		✗	SET_WRAPPERS();
153			}
154
155			#define v4l2_open s->open_f
156			#define v4l2_close s->close_f
157			#define v4l2_dup s->dup_f
158			#define v4l2_ioctl s->ioctl_f
159			#define v4l2_read s->read_f
160			#define v4l2_mmap s->mmap_f
161			#define v4l2_munmap s->munmap_f
162
163		✗	if (ctx->flags & AVFMT_FLAG_NONBLOCK) {
164		✗	flags |= O_NONBLOCK;
165			}
166
167		✗	fd = v4l2_open(device_path, flags, 0);
168		✗	if (fd < 0) {
169		✗	err = AVERROR(errno);
170		✗	av_log(ctx, AV_LOG_ERROR, "Cannot open video device %s: %s\n",
171		✗	device_path, av_err2str(err));
172		✗	return err;
173			}
174
175		✗	if (v4l2_ioctl(fd, VIDIOC_QUERYCAP, &cap) < 0) {
176		✗	err = AVERROR(errno);
177		✗	av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYCAP): %s\n",
178		✗	av_err2str(err));
179		✗	goto fail;
180			}
181
182		✗	av_log(ctx, AV_LOG_VERBOSE, "fd:%d capabilities:%x\n",
183			fd, cap.capabilities);
184
185		✗	if (!(cap.capabilities & V4L2_CAP_VIDEO_CAPTURE)) {
186		✗	av_log(ctx, AV_LOG_ERROR, "Not a video capture device.\n");
187		✗	err = AVERROR(ENODEV);
188		✗	goto fail;
189			}
190
191		✗	if (!(cap.capabilities & V4L2_CAP_STREAMING)) {
192		✗	av_log(ctx, AV_LOG_ERROR,
193			"The device does not support the streaming I/O method.\n");
194		✗	err = AVERROR(ENOSYS);
195		✗	goto fail;
196			}
197
198		✗	return fd;
199
200		✗	fail:
201		✗	v4l2_close(fd);
202		✗	return err;
203			}
204
205		✗	static int device_init(AVFormatContext *ctx, int *width, int *height,
206			uint32_t pixelformat)
207			{
208		✗	struct video_data *s = ctx->priv_data;
209		✗	struct v4l2_format fmt = { .type = V4L2_BUF_TYPE_VIDEO_CAPTURE };
210		✗	int res = 0;
211
212		✗	fmt.fmt.pix.width = *width;
213		✗	fmt.fmt.pix.height = *height;
214		✗	fmt.fmt.pix.pixelformat = pixelformat;
215		✗	fmt.fmt.pix.field = V4L2_FIELD_ANY;
216
217			/* Some drivers will fail and return EINVAL when the pixelformat
218			is not supported (even if type field is valid and supported) */
219		✗	if (v4l2_ioctl(s->fd, VIDIOC_S_FMT, &fmt) < 0)
220		✗	res = AVERROR(errno);
221
222		✗	if ((*width != fmt.fmt.pix.width) || (*height != fmt.fmt.pix.height)) {
223		✗	av_log(ctx, AV_LOG_INFO,
224			"The V4L2 driver changed the video from %dx%d to %dx%d\n",
225			*width, *height, fmt.fmt.pix.width, fmt.fmt.pix.height);
226		✗	*width = fmt.fmt.pix.width;
227		✗	*height = fmt.fmt.pix.height;
228			}
229
230		✗	if (pixelformat != fmt.fmt.pix.pixelformat) {
231		✗	av_log(ctx, AV_LOG_DEBUG,
232			"The V4L2 driver changed the pixel format "
233			"from 0x%08X to 0x%08X\n",
234			pixelformat, fmt.fmt.pix.pixelformat);
235		✗	res = AVERROR(EINVAL);
236			}
237
238		✗	if (fmt.fmt.pix.field == V4L2_FIELD_INTERLACED) {
239		✗	av_log(ctx, AV_LOG_DEBUG,
240			"The V4L2 driver is using the interlaced mode\n");
241		✗	s->interlaced = 1;
242			}
243
244		✗	return res;
245			}
246
247		✗	static int first_field(const struct video_data *s)
248			{
249			int res;
250			v4l2_std_id std;
251
252		✗	res = v4l2_ioctl(s->fd, VIDIOC_G_STD, &std);
253		✗	if (res < 0)
254		✗	return 0;
255		✗	if (std & V4L2_STD_NTSC)
256		✗	return 0;
257
258		✗	return 1;
259			}
260
261			#if HAVE_STRUCT_V4L2_FRMIVALENUM_DISCRETE
262		✗	static void list_framesizes(AVFormatContext *ctx, uint32_t pixelformat)
263			{
264		✗	const struct video_data *s = ctx->priv_data;
265		✗	struct v4l2_frmsizeenum vfse = { .pixel_format = pixelformat };
266
267		✗	while(!v4l2_ioctl(s->fd, VIDIOC_ENUM_FRAMESIZES, &vfse)) {
268		✗	switch (vfse.type) {
269		✗	case V4L2_FRMSIZE_TYPE_DISCRETE:
270		✗	av_log(ctx, AV_LOG_INFO, " %ux%u",
271			vfse.discrete.width, vfse.discrete.height);
272		✗	break;
273		✗	case V4L2_FRMSIZE_TYPE_CONTINUOUS:
274			case V4L2_FRMSIZE_TYPE_STEPWISE:
275		✗	av_log(ctx, AV_LOG_INFO, " {%u-%u, %u}x{%u-%u, %u}",
276			vfse.stepwise.min_width,
277			vfse.stepwise.max_width,
278			vfse.stepwise.step_width,
279			vfse.stepwise.min_height,
280			vfse.stepwise.max_height,
281			vfse.stepwise.step_height);
282			}
283		✗	vfse.index++;
284			}
285		✗	}
286			#endif
287
288		✗	static void list_formats(AVFormatContext *ctx, int type)
289			{
290		✗	const struct video_data *s = ctx->priv_data;
291		✗	struct v4l2_fmtdesc vfd = { .type = V4L2_BUF_TYPE_VIDEO_CAPTURE };
292
293		✗	while(!v4l2_ioctl(s->fd, VIDIOC_ENUM_FMT, &vfd)) {
294		✗	enum AVCodecID codec_id = ff_fmt_v4l2codec(vfd.pixelformat);
295		✗	enum AVPixelFormat pix_fmt = ff_fmt_v4l2ff(vfd.pixelformat, codec_id);
296
297		✗	vfd.index++;
298
299		✗	if (!(vfd.flags & V4L2_FMT_FLAG_COMPRESSED) &&
300		✗	type & V4L_RAWFORMATS) {
301		✗	const char *fmt_name = av_get_pix_fmt_name(pix_fmt);
302		✗	av_log(ctx, AV_LOG_INFO, "Raw : %11s : %20s :",
303			fmt_name ? fmt_name : "Unsupported",
304			vfd.description);
305		✗	} else if (vfd.flags & V4L2_FMT_FLAG_COMPRESSED &&
306		✗	type & V4L_COMPFORMATS) {
307		✗	const AVCodecDescriptor *desc = avcodec_descriptor_get(codec_id);
308		✗	av_log(ctx, AV_LOG_INFO, "Compressed: %11s : %20s :",
309			desc ? desc->name : "Unsupported",
310			vfd.description);
311			} else {
312		✗	continue;
313			}
314
315			#ifdef V4L2_FMT_FLAG_EMULATED
316		✗	if (vfd.flags & V4L2_FMT_FLAG_EMULATED)
317		✗	av_log(ctx, AV_LOG_INFO, " Emulated :");
318			#endif
319			#if HAVE_STRUCT_V4L2_FRMIVALENUM_DISCRETE
320		✗	list_framesizes(ctx, vfd.pixelformat);
321			#endif
322		✗	av_log(ctx, AV_LOG_INFO, "\n");
323			}
324		✗	}
325
326		✗	static void list_standards(AVFormatContext *ctx)
327			{
328			int ret;
329		✗	struct video_data *s = ctx->priv_data;
330			struct v4l2_standard standard;
331
332		✗	if (s->std_id == 0)
333		✗	return;
334
335		✗	for (standard.index = 0; ; standard.index++) {
336		✗	if (v4l2_ioctl(s->fd, VIDIOC_ENUMSTD, &standard) < 0) {
337		✗	ret = AVERROR(errno);
338		✗	if (ret == AVERROR(EINVAL)) {
339		✗	break;
340			} else {
341		✗	av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_ENUMSTD): %s\n", av_err2str(ret));
342		✗	return;
343			}
344			}
345		✗	av_log(ctx, AV_LOG_INFO, "%2d, %16"PRIx64", %s\n",
346		✗	standard.index, (uint64_t)standard.id, standard.name);
347			}
348			}
349
350		✗	static int mmap_init(AVFormatContext *ctx)
351			{
352			int i, res;
353		✗	struct video_data *s = ctx->priv_data;
354		✗	struct v4l2_requestbuffers req = {
355			.type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
356			.count = desired_video_buffers,
357			.memory = V4L2_MEMORY_MMAP
358			};
359
360		✗	if (v4l2_ioctl(s->fd, VIDIOC_REQBUFS, &req) < 0) {
361		✗	res = AVERROR(errno);
362		✗	av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_REQBUFS): %s\n", av_err2str(res));
363		✗	return res;
364			}
365
366		✗	if (req.count < 2) {
367		✗	av_log(ctx, AV_LOG_ERROR, "Insufficient buffer memory\n");
368		✗	return AVERROR(ENOMEM);
369			}
370		✗	s->buffers = req.count;
371		✗	s->buf_start = av_malloc_array(s->buffers, sizeof(void *));
372		✗	if (!s->buf_start) {
373		✗	av_log(ctx, AV_LOG_ERROR, "Cannot allocate buffer pointers\n");
374		✗	return AVERROR(ENOMEM);
375			}
376		✗	s->buf_len = av_malloc_array(s->buffers, sizeof(unsigned int));
377		✗	if (!s->buf_len) {
378		✗	av_log(ctx, AV_LOG_ERROR, "Cannot allocate buffer sizes\n");
379		✗	av_freep(&s->buf_start);
380		✗	return AVERROR(ENOMEM);
381			}
382
383		✗	for (i = 0; i < req.count; i++) {
384		✗	struct v4l2_buffer buf = {
385			.type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
386			.index = i,
387			.memory = V4L2_MEMORY_MMAP
388			};
389		✗	if (v4l2_ioctl(s->fd, VIDIOC_QUERYBUF, &buf) < 0) {
390		✗	res = AVERROR(errno);
391		✗	av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYBUF): %s\n", av_err2str(res));
392		✗	return res;
393			}
394
395		✗	s->buf_len[i] = buf.length;
396		✗	if (s->frame_size > 0 && s->buf_len[i] < s->frame_size) {
397		✗	av_log(ctx, AV_LOG_ERROR,
398			"buf_len[%d] = %d < expected frame size %d\n",
399		✗	i, s->buf_len[i], s->frame_size);
400		✗	return AVERROR(ENOMEM);
401			}
402		✗	s->buf_start[i] = v4l2_mmap(NULL, buf.length,
403			PROT_READ | PROT_WRITE, MAP_SHARED,
404		✗	s->fd, buf.m.offset);
405
406		✗	if (s->buf_start[i] == MAP_FAILED) {
407		✗	res = AVERROR(errno);
408		✗	av_log(ctx, AV_LOG_ERROR, "mmap: %s\n", av_err2str(res));
409		✗	return res;
410			}
411			}
412
413		✗	return 0;
414			}
415
416		✗	static int enqueue_buffer(struct video_data *s, struct v4l2_buffer *buf)
417			{
418		✗	int res = 0;
419
420		✗	if (v4l2_ioctl(s->fd, VIDIOC_QBUF, buf) < 0) {
421		✗	res = AVERROR(errno);
422		✗	av_log(NULL, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF): %s\n", av_err2str(res));
423			} else {
424		✗	atomic_fetch_add(&s->buffers_queued, 1);
425			}
426
427		✗	return res;
428			}
429
430		✗	static void mmap_release_buffer(void *opaque, uint8_t *data)
431			{
432		✗	struct v4l2_buffer buf = { 0 };
433		✗	struct buff_data *buf_descriptor = opaque;
434		✗	struct video_data *s = buf_descriptor->s;
435
436		✗	buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
437		✗	buf.memory = V4L2_MEMORY_MMAP;
438		✗	buf.index = buf_descriptor->index;
439		✗	av_free(buf_descriptor);
440
441		✗	enqueue_buffer(s, &buf);
442		✗	}
443
444			#if HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC)
445		✗	static int64_t av_gettime_monotonic(void)
446			{
447		✗	return av_gettime_relative();
448			}
449			#endif
450
451		✗	static int init_convert_timestamp(AVFormatContext *ctx, int64_t ts)
452			{
453		✗	struct video_data *s = ctx->priv_data;
454			int64_t now;
455
456		✗	now = av_gettime();
457		✗	if (s->ts_mode == V4L_TS_ABS &&
458		✗	ts <= now + 1 * AV_TIME_BASE && ts >= now - 10 * AV_TIME_BASE) {
459		✗	av_log(ctx, AV_LOG_INFO, "Detected absolute timestamps\n");
460		✗	s->ts_mode = V4L_TS_CONVERT_READY;
461		✗	return 0;
462			}
463			#if HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC)
464		✗	if (ctx->streams[0]->avg_frame_rate.num) {
465		✗	now = av_gettime_monotonic();
466		✗	if (s->ts_mode == V4L_TS_MONO2ABS ||
467		✗	(ts <= now + 1 * AV_TIME_BASE && ts >= now - 10 * AV_TIME_BASE)) {
468		✗	AVRational tb = {AV_TIME_BASE, 1};
469		✗	int64_t period = av_rescale_q(1, tb, ctx->streams[0]->avg_frame_rate);
470		✗	av_log(ctx, AV_LOG_INFO, "Detected monotonic timestamps, converting\n");
471			/* microseconds instead of seconds, MHz instead of Hz */
472		✗	s->timefilter = ff_timefilter_new(1, period, 1.0E-6);
473		✗	if (!s->timefilter)
474		✗	return AVERROR(ENOMEM);
475		✗	s->ts_mode = V4L_TS_CONVERT_READY;
476		✗	return 0;
477			}
478			}
479			#endif
480		✗	av_log(ctx, AV_LOG_ERROR, "Unknown timestamps\n");
481		✗	return AVERROR(EIO);
482			}
483
484		✗	static int convert_timestamp(AVFormatContext *ctx, int64_t *ts)
485			{
486		✗	struct video_data *s = ctx->priv_data;
487
488		✗	if (s->ts_mode) {
489		✗	int r = init_convert_timestamp(ctx, *ts);
490		✗	if (r < 0)
491		✗	return r;
492			}
493			#if HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC)
494		✗	if (s->timefilter) {
495		✗	int64_t nowa = av_gettime();
496		✗	int64_t nowm = av_gettime_monotonic();
497		✗	ff_timefilter_update(s->timefilter, nowa, nowm - s->last_time_m);
498		✗	s->last_time_m = nowm;
499		✗	*ts = ff_timefilter_eval(s->timefilter, *ts - nowm);
500			}
501			#endif
502		✗	return 0;
503			}
504
505		✗	static int mmap_read_frame(AVFormatContext *ctx, AVPacket *pkt)
506			{
507		✗	struct video_data *s = ctx->priv_data;
508		✗	struct v4l2_buffer buf = {
509			.type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
510			.memory = V4L2_MEMORY_MMAP
511			};
512			struct timeval buf_ts;
513			int res;
514
515		✗	pkt->size = 0;
516
517			/* FIXME: Some special treatment might be needed in case of loss of signal... */
518		✗	while ((res = v4l2_ioctl(s->fd, VIDIOC_DQBUF, &buf)) < 0 && (errno == EINTR));
519		✗	if (res < 0) {
520		✗	if (errno == EAGAIN)
521		✗	return AVERROR(EAGAIN);
522
523		✗	res = AVERROR(errno);
524		✗	av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_DQBUF): %s\n",
525		✗	av_err2str(res));
526		✗	return res;
527			}
528
529		✗	buf_ts = buf.timestamp;
530
531		✗	if (buf.index >= s->buffers) {
532		✗	av_log(ctx, AV_LOG_ERROR, "Invalid buffer index received.\n");
533		✗	return AVERROR(EINVAL);
534			}
535		✗	atomic_fetch_add(&s->buffers_queued, -1);
536			// always keep at least one buffer queued
537		✗	av_assert0(atomic_load(&s->buffers_queued) >= 1);
538
539			#ifdef V4L2_BUF_FLAG_ERROR
540		✗	if (buf.flags & V4L2_BUF_FLAG_ERROR) {
541		✗	av_log(ctx, AV_LOG_WARNING,
542			"Dequeued v4l2 buffer contains corrupted data (%d bytes).\n",
543			buf.bytesused);
544		✗	buf.bytesused = 0;
545			} else
546			#endif
547			{
548			/* CPIA is a compressed format and we don't know the exact number of bytes
549			* used by a frame, so set it here as the driver announces it. */
550		✗	if (ctx->video_codec_id == AV_CODEC_ID_CPIA)
551		✗	s->frame_size = buf.bytesused;
552
553		✗	if (s->frame_size > 0 && buf.bytesused != s->frame_size) {
554		✗	av_log(ctx, AV_LOG_WARNING,
555			"Dequeued v4l2 buffer contains %d bytes, but %d were expected. Flags: 0x%08X.\n",
556			buf.bytesused, s->frame_size, buf.flags);
557		✗	buf.bytesused = 0;
558			}
559			}
560
561			/* Image is at s->buff_start[buf.index] */
562		✗	if (atomic_load(&s->buffers_queued) == FFMAX(s->buffers / 8, 1)) {
563			/* when we start getting low on queued buffers, fall back on copying data */
564		✗	res = av_new_packet(pkt, buf.bytesused);
565		✗	if (res < 0) {
566		✗	av_log(ctx, AV_LOG_ERROR, "Error allocating a packet.\n");
567		✗	enqueue_buffer(s, &buf);
568		✗	return res;
569			}
570		✗	memcpy(pkt->data, s->buf_start[buf.index], buf.bytesused);
571
572		✗	res = enqueue_buffer(s, &buf);
573		✗	if (res) {
574		✗	av_packet_unref(pkt);
575		✗	return res;
576			}
577			} else {
578			struct buff_data *buf_descriptor;
579
580		✗	pkt->data = s->buf_start[buf.index];
581		✗	pkt->size = buf.bytesused;
582
583		✗	buf_descriptor = av_malloc(sizeof(struct buff_data));
584		✗	if (!buf_descriptor) {
585			/* Something went wrong... Since av_malloc() failed, we cannot even
586			* allocate a buffer for memcpying into it
587			*/
588		✗	av_log(ctx, AV_LOG_ERROR, "Failed to allocate a buffer descriptor\n");
589		✗	enqueue_buffer(s, &buf);
590
591		✗	return AVERROR(ENOMEM);
592			}
593		✗	buf_descriptor->index = buf.index;
594		✗	buf_descriptor->s = s;
595
596		✗	pkt->buf = av_buffer_create(pkt->data, pkt->size, mmap_release_buffer,
597			buf_descriptor, 0);
598		✗	if (!pkt->buf) {
599		✗	av_log(ctx, AV_LOG_ERROR, "Failed to create a buffer\n");
600		✗	enqueue_buffer(s, &buf);
601		✗	av_freep(&buf_descriptor);
602		✗	return AVERROR(ENOMEM);
603			}
604			}
605		✗	pkt->pts = buf_ts.tv_sec * INT64_C(1000000) + buf_ts.tv_usec;
606		✗	convert_timestamp(ctx, &pkt->pts);
607
608		✗	return pkt->size;
609			}
610
611		✗	static int mmap_start(AVFormatContext *ctx)
612			{
613		✗	struct video_data *s = ctx->priv_data;
614			enum v4l2_buf_type type;
615			int i, res;
616
617		✗	for (i = 0; i < s->buffers; i++) {
618		✗	struct v4l2_buffer buf = {
619			.type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
620			.index = i,
621			.memory = V4L2_MEMORY_MMAP
622			};
623
624		✗	if (v4l2_ioctl(s->fd, VIDIOC_QBUF, &buf) < 0) {
625		✗	res = AVERROR(errno);
626		✗	av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF): %s\n",
627		✗	av_err2str(res));
628		✗	return res;
629			}
630			}
631		✗	atomic_store(&s->buffers_queued, s->buffers);
632
633		✗	type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
634		✗	if (v4l2_ioctl(s->fd, VIDIOC_STREAMON, &type) < 0) {
635		✗	res = AVERROR(errno);
636		✗	av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_STREAMON): %s\n",
637		✗	av_err2str(res));
638		✗	return res;
639			}
640
641		✗	return 0;
642			}
643
644		✗	static void mmap_close(struct video_data *s)
645			{
646			enum v4l2_buf_type type;
647			int i;
648
649		✗	type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
650			/* We do not check for the result, because we could
651			* not do anything about it anyway...
652			*/
653		✗	v4l2_ioctl(s->fd, VIDIOC_STREAMOFF, &type);
654		✗	for (i = 0; i < s->buffers; i++) {
655		✗	v4l2_munmap(s->buf_start[i], s->buf_len[i]);
656			}
657		✗	av_freep(&s->buf_start);
658		✗	av_freep(&s->buf_len);
659		✗	}
660
661		✗	static int v4l2_set_parameters(AVFormatContext *ctx)
662			{
663		✗	struct video_data *s = ctx->priv_data;
664		✗	struct v4l2_standard standard = { 0 };
665		✗	struct v4l2_streamparm streamparm = { 0 };
666			struct v4l2_fract *tpf;
667		✗	AVRational framerate_q = { 0 };
668			int i, ret;
669
670		✗	if (s->framerate &&
671		✗	(ret = av_parse_video_rate(&framerate_q, s->framerate)) < 0) {
672		✗	av_log(ctx, AV_LOG_ERROR, "Could not parse framerate '%s'.\n",
673			s->framerate);
674		✗	return ret;
675			}
676
677		✗	if (s->standard) {
678		✗	if (s->std_id) {
679		✗	ret = 0;
680		✗	av_log(ctx, AV_LOG_DEBUG, "Setting standard: %s\n", s->standard);
681			/* set tv standard */
682		✗	for (i = 0; ; i++) {
683		✗	standard.index = i;
684		✗	if (v4l2_ioctl(s->fd, VIDIOC_ENUMSTD, &standard) < 0) {
685		✗	ret = AVERROR(errno);
686		✗	break;
687			}
688		✗	if (!av_strcasecmp(standard.name, s->standard))
689		✗	break;
690			}
691		✗	if (ret < 0) {
692		✗	av_log(ctx, AV_LOG_ERROR, "Unknown or unsupported standard '%s'\n", s->standard);
693		✗	return ret;
694			}
695
696		✗	if (v4l2_ioctl(s->fd, VIDIOC_S_STD, &standard.id) < 0) {
697		✗	ret = AVERROR(errno);
698		✗	av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_S_STD): %s\n", av_err2str(ret));
699		✗	return ret;
700			}
701			} else {
702		✗	av_log(ctx, AV_LOG_WARNING,
703			"This device does not support any standard\n");
704			}
705			}
706
707			/* get standard */
708		✗	if (v4l2_ioctl(s->fd, VIDIOC_G_STD, &s->std_id) == 0) {
709		✗	tpf = &standard.frameperiod;
710		✗	for (i = 0; ; i++) {
711		✗	standard.index = i;
712		✗	if (v4l2_ioctl(s->fd, VIDIOC_ENUMSTD, &standard) < 0) {
713		✗	ret = AVERROR(errno);
714		✗	if (ret == AVERROR(EINVAL)
715			#ifdef ENODATA
716		✗	|| ret == AVERROR(ENODATA)
717			#endif
718			) {
719		✗	tpf = &streamparm.parm.capture.timeperframe;
720		✗	break;
721			}
722		✗	av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_ENUMSTD): %s\n", av_err2str(ret));
723		✗	return ret;
724			}
725		✗	if (standard.id == s->std_id) {
726		✗	av_log(ctx, AV_LOG_DEBUG,
727			"Current standard: %s, id: %"PRIx64", frameperiod: %d/%d\n",
728		✗	standard.name, (uint64_t)standard.id, tpf->numerator, tpf->denominator);
729		✗	break;
730			}
731			}
732			} else {
733		✗	tpf = &streamparm.parm.capture.timeperframe;
734			}
735
736		✗	streamparm.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
737		✗	if (v4l2_ioctl(s->fd, VIDIOC_G_PARM, &streamparm) < 0) {
738		✗	ret = AVERROR(errno);
739		✗	av_log(ctx, AV_LOG_WARNING, "ioctl(VIDIOC_G_PARM): %s\n", av_err2str(ret));
740		✗	} else if (framerate_q.num && framerate_q.den) {
741		✗	if (streamparm.parm.capture.capability & V4L2_CAP_TIMEPERFRAME) {
742		✗	tpf = &streamparm.parm.capture.timeperframe;
743
744		✗	av_log(ctx, AV_LOG_DEBUG, "Setting time per frame to %d/%d\n",
745			framerate_q.den, framerate_q.num);
746		✗	tpf->numerator = framerate_q.den;
747		✗	tpf->denominator = framerate_q.num;
748
749		✗	if (v4l2_ioctl(s->fd, VIDIOC_S_PARM, &streamparm) < 0) {
750		✗	ret = AVERROR(errno);
751		✗	av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_S_PARM): %s\n",
752		✗	av_err2str(ret));
753		✗	return ret;
754			}
755
756		✗	if (framerate_q.num != tpf->denominator ||
757		✗	framerate_q.den != tpf->numerator) {
758		✗	av_log(ctx, AV_LOG_INFO,
759			"The driver changed the time per frame from "
760			"%d/%d to %d/%d\n",
761			framerate_q.den, framerate_q.num,
762			tpf->numerator, tpf->denominator);
763			}
764			} else {
765		✗	av_log(ctx, AV_LOG_WARNING,
766			"The driver does not permit changing the time per frame\n");
767			}
768			}
769		✗	if (tpf->denominator > 0 && tpf->numerator > 0) {
770		✗	ctx->streams[0]->avg_frame_rate.num = tpf->denominator;
771		✗	ctx->streams[0]->avg_frame_rate.den = tpf->numerator;
772		✗	ctx->streams[0]->r_frame_rate = ctx->streams[0]->avg_frame_rate;
773			} else
774		✗	av_log(ctx, AV_LOG_WARNING, "Time per frame unknown\n");
775
776		✗	return 0;
777			}
778
779		✗	static int device_try_init(AVFormatContext *ctx,
780			enum AVPixelFormat pix_fmt,
781			int *width,
782			int *height,
783			uint32_t *desired_format,
784			enum AVCodecID *codec_id)
785			{
786			int ret, i;
787
788		✗	*desired_format = ff_fmt_ff2v4l(pix_fmt, ctx->video_codec_id);
789
790		✗	if (*desired_format) {
791		✗	ret = device_init(ctx, width, height, *desired_format);
792		✗	if (ret < 0) {
793		✗	*desired_format = 0;
794		✗	if (ret != AVERROR(EINVAL))
795		✗	return ret;
796			}
797			}
798
799		✗	if (!*desired_format) {
800		✗	for (i = 0; ff_fmt_conversion_table[i].codec_id != AV_CODEC_ID_NONE; i++) {
801		✗	if (ctx->video_codec_id == AV_CODEC_ID_NONE ||
802		✗	ff_fmt_conversion_table[i].codec_id == ctx->video_codec_id) {
803		✗	av_log(ctx, AV_LOG_DEBUG, "Trying to set codec:%s pix_fmt:%s\n",
804		✗	avcodec_get_name(ff_fmt_conversion_table[i].codec_id),
805		✗	(char *)av_x_if_null(av_get_pix_fmt_name(ff_fmt_conversion_table[i].ff_fmt), "none"));
806
807		✗	*desired_format = ff_fmt_conversion_table[i].v4l2_fmt;
808		✗	ret = device_init(ctx, width, height, *desired_format);
809		✗	if (ret >= 0)
810		✗	break;
811		✗	else if (ret != AVERROR(EINVAL))
812		✗	return ret;
813		✗	*desired_format = 0;
814			}
815			}
816
817		✗	if (*desired_format == 0) {
818		✗	av_log(ctx, AV_LOG_ERROR, "Cannot find a proper format for "
819			"codec '%s' (id %d), pixel format '%s' (id %d)\n",
820		✗	avcodec_get_name(ctx->video_codec_id), ctx->video_codec_id,
821		✗	(char *)av_x_if_null(av_get_pix_fmt_name(pix_fmt), "none"), pix_fmt);
822		✗	ret = AVERROR(EINVAL);
823			}
824			}
825
826		✗	*codec_id = ff_fmt_v4l2codec(*desired_format);
827		✗	if (*codec_id == AV_CODEC_ID_NONE)
828		✗	av_assert0(ret == AVERROR(EINVAL));
829		✗	return ret;
830			}
831
832		3664	static int v4l2_read_probe(const AVProbeData *p)
833			{
834	1/2 ✗ Branch 1 not taken. ✓ Branch 2 taken 3664 times.	3664	if (av_strstart(p->filename, "/dev/video", NULL))
835		✗	return AVPROBE_SCORE_MAX - 1;
836		3664	return 0;
837			}
838
839		✗	static int v4l2_read_header(AVFormatContext *ctx)
840			{
841		✗	struct video_data *s = ctx->priv_data;
842			AVStream *st;
843		✗	int res = 0;
844			uint32_t desired_format;
845		✗	enum AVCodecID codec_id = AV_CODEC_ID_NONE;
846		✗	enum AVPixelFormat pix_fmt = AV_PIX_FMT_NONE;
847		✗	struct v4l2_input input = { 0 };
848
849		✗	st = avformat_new_stream(ctx, NULL);
850		✗	if (!st)
851		✗	return AVERROR(ENOMEM);
852
853			#if CONFIG_LIBV4L2
854			/* silence libv4l2 logging. if fopen() fails v4l2_log_file will be NULL
855			and errors will get sent to stderr */
856			if (s->use_libv4l2)
857			v4l2_log_file = fopen("/dev/null", "w");
858			#endif
859
860		✗	s->fd = device_open(ctx, ctx->url);
861		✗	if (s->fd < 0)
862		✗	return s->fd;
863
864		✗	if (s->channel != -1) {
865			/* set video input */
866		✗	av_log(ctx, AV_LOG_DEBUG, "Selecting input_channel: %d\n", s->channel);
867		✗	if (v4l2_ioctl(s->fd, VIDIOC_S_INPUT, &s->channel) < 0) {
868		✗	res = AVERROR(errno);
869		✗	av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_S_INPUT): %s\n", av_err2str(res));
870		✗	goto fail;
871			}
872			} else {
873			/* get current video input */
874		✗	if (v4l2_ioctl(s->fd, VIDIOC_G_INPUT, &s->channel) < 0) {
875		✗	res = AVERROR(errno);
876		✗	av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_G_INPUT): %s\n", av_err2str(res));
877		✗	goto fail;
878			}
879			}
880
881			/* enum input */
882		✗	input.index = s->channel;
883		✗	if (v4l2_ioctl(s->fd, VIDIOC_ENUMINPUT, &input) < 0) {
884		✗	res = AVERROR(errno);
885		✗	av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_ENUMINPUT): %s\n", av_err2str(res));
886		✗	goto fail;
887			}
888		✗	s->std_id = input.std;
889		✗	av_log(ctx, AV_LOG_DEBUG, "Current input_channel: %d, input_name: %s, input_std: %"PRIx64"\n",
890		✗	s->channel, input.name, (uint64_t)input.std);
891
892		✗	if (s->list_format) {
893		✗	list_formats(ctx, s->list_format);
894		✗	res = AVERROR_EXIT;
895		✗	goto fail;
896			}
897
898		✗	if (s->list_standard) {
899		✗	list_standards(ctx);
900		✗	res = AVERROR_EXIT;
901		✗	goto fail;
902			}
903
904		✗	avpriv_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
905
906		✗	if (s->pixel_format) {
907		✗	const AVCodecDescriptor *desc = avcodec_descriptor_get_by_name(s->pixel_format);
908
909		✗	if (desc)
910		✗	ctx->video_codec_id = desc->id;
911
912		✗	pix_fmt = av_get_pix_fmt(s->pixel_format);
913
914		✗	if (pix_fmt == AV_PIX_FMT_NONE && !desc) {
915		✗	av_log(ctx, AV_LOG_ERROR, "No such input format: %s.\n",
916			s->pixel_format);
917
918		✗	res = AVERROR(EINVAL);
919		✗	goto fail;
920			}
921			}
922
923		✗	if (!s->width && !s->height) {
924		✗	struct v4l2_format fmt = { .type = V4L2_BUF_TYPE_VIDEO_CAPTURE };
925
926		✗	av_log(ctx, AV_LOG_VERBOSE,
927			"Querying the device for the current frame size\n");
928		✗	if (v4l2_ioctl(s->fd, VIDIOC_G_FMT, &fmt) < 0) {
929		✗	res = AVERROR(errno);
930		✗	av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_G_FMT): %s\n",
931		✗	av_err2str(res));
932		✗	goto fail;
933			}
934
935		✗	s->width = fmt.fmt.pix.width;
936		✗	s->height = fmt.fmt.pix.height;
937		✗	av_log(ctx, AV_LOG_VERBOSE,
938			"Setting frame size to %dx%d\n", s->width, s->height);
939			}
940
941		✗	res = device_try_init(ctx, pix_fmt, &s->width, &s->height, &desired_format, &codec_id);
942		✗	if (res < 0)
943		✗	goto fail;
944
945			/* If no pixel_format was specified, the codec_id was not known up
946			* until now. Set video_codec_id in the context, as codec_id will
947			* not be available outside this function
948			*/
949		✗	if (codec_id != AV_CODEC_ID_NONE && ctx->video_codec_id == AV_CODEC_ID_NONE)
950		✗	ctx->video_codec_id = codec_id;
951
952		✗	if ((res = av_image_check_size(s->width, s->height, 0, ctx)) < 0)
953		✗	goto fail;
954
955		✗	s->pixelformat = desired_format;
956
957		✗	if ((res = v4l2_set_parameters(ctx)) < 0)
958		✗	goto fail;
959
960		✗	st->codecpar->format = ff_fmt_v4l2ff(desired_format, codec_id);
961		✗	if (st->codecpar->format != AV_PIX_FMT_NONE)
962		✗	s->frame_size = av_image_get_buffer_size(st->codecpar->format,
963			s->width, s->height, 1);
964
965		✗	if ((res = mmap_init(ctx)) ||
966		✗	(res = mmap_start(ctx)) < 0)
967		✗	goto fail;
968
969		✗	s->top_field_first = first_field(s);
970
971		✗	st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
972		✗	st->codecpar->codec_id = codec_id;
973		✗	if (codec_id == AV_CODEC_ID_RAWVIDEO)
974		✗	st->codecpar->codec_tag =
975		✗	avcodec_pix_fmt_to_codec_tag(st->codecpar->format);
976		✗	else if (codec_id == AV_CODEC_ID_H264) {
977		✗	avpriv_stream_set_need_parsing(st, AVSTREAM_PARSE_FULL_ONCE);
978			}
979		✗	if (desired_format == V4L2_PIX_FMT_YVU420)
980		✗	st->codecpar->codec_tag = MKTAG('Y', 'V', '1', '2');
981		✗	else if (desired_format == V4L2_PIX_FMT_YVU410)
982		✗	st->codecpar->codec_tag = MKTAG('Y', 'V', 'U', '9');
983		✗	st->codecpar->width = s->width;
984		✗	st->codecpar->height = s->height;
985		✗	if (st->avg_frame_rate.den)
986		✗	st->codecpar->bit_rate = s->frame_size * av_q2d(st->avg_frame_rate) * 8;
987
988		✗	return 0;
989
990		✗	fail:
991		✗	v4l2_close(s->fd);
992		✗	return res;
993			}
994
995		✗	static int v4l2_read_packet(AVFormatContext *ctx, AVPacket *pkt)
996			{
997			int res;
998
999		✗	if ((res = mmap_read_frame(ctx, pkt)) < 0) {
1000		✗	return res;
1001			}
1002
1003		✗	return pkt->size;
1004			}
1005
1006		✗	static int v4l2_read_close(AVFormatContext *ctx)
1007			{
1008		✗	struct video_data *s = ctx->priv_data;
1009
1010		✗	if (atomic_load(&s->buffers_queued) != s->buffers)
1011		✗	av_log(ctx, AV_LOG_WARNING, "Some buffers are still owned by the caller on "
1012			"close.\n");
1013
1014		✗	mmap_close(s);
1015
1016		✗	ff_timefilter_destroy(s->timefilter);
1017		✗	v4l2_close(s->fd);
1018		✗	return 0;
1019			}
1020
1021		✗	static int v4l2_is_v4l_dev(const char *name)
1022			{
1023		✗	return !strncmp(name, "video", 5) ||
1024		✗	!strncmp(name, "radio", 5) ||
1025		✗	!strncmp(name, "vbi", 3) ||
1026		✗	!strncmp(name, "v4l-subdev", 10);
1027			}
1028
1029		✗	static int v4l2_get_device_list(AVFormatContext *ctx, AVDeviceInfoList *device_list)
1030			{
1031		✗	struct video_data *s = ctx->priv_data;
1032			DIR *dir;
1033			struct dirent *entry;
1034		✗	int ret = 0;
1035
1036		✗	if (!device_list)
1037		✗	return AVERROR(EINVAL);
1038
1039		✗	dir = opendir("/dev");
1040		✗	if (!dir) {
1041		✗	ret = AVERROR(errno);
1042		✗	av_log(ctx, AV_LOG_ERROR, "Couldn't open the directory: %s\n", av_err2str(ret));
1043		✗	return ret;
1044			}
1045		✗	while ((entry = readdir(dir))) {
1046		✗	AVDeviceInfo *device = NULL;
1047			struct v4l2_capability cap;
1048		✗	int fd = -1, size;
1049			char device_name[256];
1050
1051		✗	if (!v4l2_is_v4l_dev(entry->d_name))
1052		✗	continue;
1053
1054		✗	size = snprintf(device_name, sizeof(device_name), "/dev/%s", entry->d_name);
1055		✗	if (size >= sizeof(device_name)) {
1056		✗	av_log(ctx, AV_LOG_ERROR, "Device name too long.\n");
1057		✗	ret = AVERROR(ENOSYS);
1058		✗	break;
1059			}
1060
1061		✗	if ((fd = device_open(ctx, device_name)) < 0)
1062		✗	continue;
1063
1064		✗	if (v4l2_ioctl(fd, VIDIOC_QUERYCAP, &cap) < 0) {
1065		✗	ret = AVERROR(errno);
1066		✗	av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYCAP): %s\n", av_err2str(ret));
1067		✗	goto fail;
1068			}
1069
1070		✗	device = av_mallocz(sizeof(AVDeviceInfo));
1071		✗	if (!device) {
1072		✗	ret = AVERROR(ENOMEM);
1073		✗	goto fail;
1074			}
1075		✗	device->device_name = av_strdup(device_name);
1076		✗	device->device_description = av_strdup(cap.card);
1077		✗	if (!device->device_name || !device->device_description) {
1078		✗	ret = AVERROR(ENOMEM);
1079		✗	goto fail;
1080			}
1081
1082		✗	if ((ret = av_dynarray_add_nofree(&device_list->devices,
1083			&device_list->nb_devices, device)) < 0)
1084		✗	goto fail;
1085
1086		✗	v4l2_close(fd);
1087		✗	continue;
1088
1089		✗	fail:
1090		✗	if (device) {
1091		✗	av_freep(&device->device_name);
1092		✗	av_freep(&device->device_description);
1093		✗	av_freep(&device);
1094			}
1095		✗	v4l2_close(fd);
1096		✗	break;
1097			}
1098		✗	closedir(dir);
1099		✗	return ret;
1100			}
1101
1102			#define OFFSET(x) offsetof(struct video_data, x)
1103			#define DEC AV_OPT_FLAG_DECODING_PARAM
1104
1105			static const AVOption options[] = {
1106			{ "standard", "set TV standard, used only by analog frame grabber", OFFSET(standard), AV_OPT_TYPE_STRING, {.str = NULL }, 0, 0, DEC },
1107			{ "channel", "set TV channel, used only by frame grabber", OFFSET(channel), AV_OPT_TYPE_INT, {.i64 = -1 }, -1, INT_MAX, DEC },
1108			{ "video_size", "set frame size", OFFSET(width), AV_OPT_TYPE_IMAGE_SIZE, {.str = NULL}, 0, 0, DEC },
1109			{ "pixel_format", "set preferred pixel format", OFFSET(pixel_format), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
1110			{ "input_format", "set preferred pixel format (for raw video) or codec name", OFFSET(pixel_format), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
1111			{ "framerate", "set frame rate", OFFSET(framerate), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
1112
1113			{ "list_formats", "list available formats and exit", OFFSET(list_format), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, DEC, .unit = "list_formats" },
1114			{ "all", "show all available formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.i64 = V4L_ALLFORMATS }, 0, INT_MAX, DEC, .unit = "list_formats" },
1115			{ "raw", "show only non-compressed formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.i64 = V4L_RAWFORMATS }, 0, INT_MAX, DEC, .unit = "list_formats" },
1116			{ "compressed", "show only compressed formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.i64 = V4L_COMPFORMATS }, 0, INT_MAX, DEC, .unit = "list_formats" },
1117
1118			{ "list_standards", "list supported standards and exit", OFFSET(list_standard), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 1, DEC, .unit = "list_standards" },
1119			{ "all", "show all supported standards", OFFSET(list_standard), AV_OPT_TYPE_CONST, {.i64 = 1 }, 0, 0, DEC, .unit = "list_standards" },
1120
1121			{ "timestamps", "set type of timestamps for grabbed frames", OFFSET(ts_mode), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 2, DEC, .unit = "timestamps" },
1122			{ "ts", "set type of timestamps for grabbed frames", OFFSET(ts_mode), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 2, DEC, .unit = "timestamps" },
1123			{ "default", "use timestamps from the kernel", OFFSET(ts_mode), AV_OPT_TYPE_CONST, {.i64 = V4L_TS_DEFAULT }, 0, 2, DEC, .unit = "timestamps" },
1124			{ "abs", "use absolute timestamps (wall clock)", OFFSET(ts_mode), AV_OPT_TYPE_CONST, {.i64 = V4L_TS_ABS }, 0, 2, DEC, .unit = "timestamps" },
1125			{ "mono2abs", "force conversion from monotonic to absolute timestamps", OFFSET(ts_mode), AV_OPT_TYPE_CONST, {.i64 = V4L_TS_MONO2ABS }, 0, 2, DEC, .unit = "timestamps" },
1126			{ "use_libv4l2", "use libv4l2 (v4l-utils) conversion functions", OFFSET(use_libv4l2), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, DEC },
1127			{ NULL },
1128			};
1129
1130			static const AVClass v4l2_class = {
1131			.class_name = "V4L2 indev",
1132			.item_name = av_default_item_name,
1133			.option = options,
1134			.version = LIBAVUTIL_VERSION_INT,
1135			.category = AV_CLASS_CATEGORY_DEVICE_VIDEO_INPUT,
1136			};
1137
1138			const FFInputFormat ff_v4l2_demuxer = {
1139			.p.name = "video4linux2,v4l2",
1140			.p.long_name = NULL_IF_CONFIG_SMALL("Video4Linux2 device grab"),
1141			.p.flags = AVFMT_NOFILE,
1142			.p.priv_class = &v4l2_class,
1143			.priv_data_size = sizeof(struct video_data),
1144			.read_probe = v4l2_read_probe,
1145			.read_header = v4l2_read_header,
1146			.read_packet = v4l2_read_packet,
1147			.read_close = v4l2_read_close,
1148			.get_device_list = v4l2_get_device_list,
1149			};
1150