2 * Copyright (c) 2000,2001 Fabrice Bellard
3 * Copyright (c) 2006 Luca Abeni
5 * This file is part of FFmpeg.
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.
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.
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
24 * Video4Linux2 grab interface
26 * Part of this file is based on the V4L2 video capture example
27 * (http://linuxtv.org/downloads/v4l-dvb-apis/capture-example.html)
29 * Thanks to Michael Niedermayer for providing the mapping between
30 * V4L2_PIX_FMT_* and AV_PIX_FMT_*
33 #include "v4l2-common.h"
39 static const int desired_video_buffers
= 256;
41 #define V4L_ALLFORMATS 3
42 #define V4L_RAWFORMATS 1
43 #define V4L_COMPFORMATS 2
46 * Return timestamps to the user exactly as returned by the kernel
48 #define V4L_TS_DEFAULT 0
50 * Autodetect the kind of timestamps returned by the kernel and convert to
51 * absolute (wall clock) timestamps.
55 * Assume kernel timestamps are from the monotonic clock and convert to
56 * absolute timestamps.
58 #define V4L_TS_MONO2ABS 2
61 * Once the kind of timestamps returned by the kernel have been detected,
62 * the value of the timefilter (NULL or not) determines whether a conversion
65 #define V4L_TS_CONVERT_READY V4L_TS_DEFAULT
70 int pixelformat
; /* V4L2_PIX_FMT_* */
76 TimeFilter
*timefilter
;
80 volatile int buffers_queued
;
82 unsigned int *buf_len
;
86 char *pixel_format
; /**< Set by a private option. */
87 int list_format
; /**< Set by a private option. */
88 int list_standard
; /**< Set by a private option. */
89 char *framerate
; /**< Set by a private option. */
92 int (*open_f
)(const char *file
, int oflag
, ...);
93 int (*close_f
)(int fd
);
95 int (*ioctl_f
)(int fd
, unsigned long int request
, ...);
96 ssize_t (*read_f
)(int fd
, void *buffer
, size_t n
);
97 void *(*mmap_f
)(void *start
, size_t length
, int prot
, int flags
, int fd
, int64_t offset
);
98 int (*munmap_f
)(void *_start
, size_t length
);
102 struct video_data
*s
;
106 static int device_open(AVFormatContext
*ctx
)
108 struct video_data
*s
= ctx
->priv_data
;
109 struct v4l2_capability cap
;
114 #define SET_WRAPPERS(prefix) do { \
115 s->open_f = prefix ## open; \
116 s->close_f = prefix ## close; \
117 s->dup_f = prefix ## dup; \
118 s->ioctl_f = prefix ## ioctl; \
119 s->read_f = prefix ## read; \
120 s->mmap_f = prefix ## mmap; \
121 s->munmap_f = prefix ## munmap; \
124 if (s
->use_libv4l2
) {
128 av_log(ctx
, AV_LOG_ERROR
, "libavdevice is not build with libv4l2 support.\n");
129 return AVERROR(EINVAL
);
135 #define v4l2_open s->open_f
136 #define v4l2_close s->close_f
137 #define v4l2_dup s->dup_f
138 #define v4l2_ioctl s->ioctl_f
139 #define v4l2_read s->read_f
140 #define v4l2_mmap s->mmap_f
141 #define v4l2_munmap s->munmap_f
143 if (ctx
->flags
& AVFMT_FLAG_NONBLOCK
) {
147 fd
= v4l2_open(ctx
->filename
, flags
, 0);
149 err
= AVERROR(errno
);
150 av_log(ctx
, AV_LOG_ERROR
, "Cannot open video device %s: %s\n",
151 ctx
->filename
, av_err2str(err
));
155 if (v4l2_ioctl(fd
, VIDIOC_QUERYCAP
, &cap
) < 0) {
156 err
= AVERROR(errno
);
157 av_log(ctx
, AV_LOG_ERROR
, "ioctl(VIDIOC_QUERYCAP): %s\n",
162 av_log(ctx
, AV_LOG_VERBOSE
, "fd:%d capabilities:%x\n",
163 fd
, cap
.capabilities
);
165 if (!(cap
.capabilities
& V4L2_CAP_VIDEO_CAPTURE
)) {
166 av_log(ctx
, AV_LOG_ERROR
, "Not a video capture device.\n");
167 err
= AVERROR(ENODEV
);
171 if (!(cap
.capabilities
& V4L2_CAP_STREAMING
)) {
172 av_log(ctx
, AV_LOG_ERROR
,
173 "The device does not support the streaming I/O method.\n");
174 err
= AVERROR(ENOSYS
);
185 static int device_init(AVFormatContext
*ctx
, int *width
, int *height
,
186 uint32_t pixelformat
)
188 struct video_data
*s
= ctx
->priv_data
;
189 struct v4l2_format fmt
= { .type
= V4L2_BUF_TYPE_VIDEO_CAPTURE
};
192 fmt
.fmt
.pix
.width
= *width
;
193 fmt
.fmt
.pix
.height
= *height
;
194 fmt
.fmt
.pix
.pixelformat
= pixelformat
;
195 fmt
.fmt
.pix
.field
= V4L2_FIELD_ANY
;
197 /* Some drivers will fail and return EINVAL when the pixelformat
198 is not supported (even if type field is valid and supported) */
199 if (v4l2_ioctl(s
->fd
, VIDIOC_S_FMT
, &fmt
) < 0)
200 res
= AVERROR(errno
);
202 if ((*width
!= fmt
.fmt
.pix
.width
) || (*height
!= fmt
.fmt
.pix
.height
)) {
203 av_log(ctx
, AV_LOG_INFO
,
204 "The V4L2 driver changed the video from %dx%d to %dx%d\n",
205 *width
, *height
, fmt
.fmt
.pix
.width
, fmt
.fmt
.pix
.height
);
206 *width
= fmt
.fmt
.pix
.width
;
207 *height
= fmt
.fmt
.pix
.height
;
210 if (pixelformat
!= fmt
.fmt
.pix
.pixelformat
) {
211 av_log(ctx
, AV_LOG_DEBUG
,
212 "The V4L2 driver changed the pixel format "
213 "from 0x%08X to 0x%08X\n",
214 pixelformat
, fmt
.fmt
.pix
.pixelformat
);
215 res
= AVERROR(EINVAL
);
218 if (fmt
.fmt
.pix
.field
== V4L2_FIELD_INTERLACED
) {
219 av_log(ctx
, AV_LOG_DEBUG
,
220 "The V4L2 driver is using the interlaced mode\n");
227 static int first_field(const struct video_data
*s
)
232 res
= v4l2_ioctl(s
->fd
, VIDIOC_G_STD
, &std
);
235 if (std
& V4L2_STD_NTSC
)
241 #if HAVE_STRUCT_V4L2_FRMIVALENUM_DISCRETE
242 static void list_framesizes(AVFormatContext
*ctx
, uint32_t pixelformat
)
244 const struct video_data
*s
= ctx
->priv_data
;
245 struct v4l2_frmsizeenum vfse
= { .pixel_format
= pixelformat
};
247 while(!v4l2_ioctl(s
->fd
, VIDIOC_ENUM_FRAMESIZES
, &vfse
)) {
249 case V4L2_FRMSIZE_TYPE_DISCRETE
:
250 av_log(ctx
, AV_LOG_INFO
, " %ux%u",
251 vfse
.discrete
.width
, vfse
.discrete
.height
);
253 case V4L2_FRMSIZE_TYPE_CONTINUOUS
:
254 case V4L2_FRMSIZE_TYPE_STEPWISE
:
255 av_log(ctx
, AV_LOG_INFO
, " {%u-%u, %u}x{%u-%u, %u}",
256 vfse
.stepwise
.min_width
,
257 vfse
.stepwise
.max_width
,
258 vfse
.stepwise
.step_width
,
259 vfse
.stepwise
.min_height
,
260 vfse
.stepwise
.max_height
,
261 vfse
.stepwise
.step_height
);
268 static void list_formats(AVFormatContext
*ctx
, int type
)
270 const struct video_data
*s
= ctx
->priv_data
;
271 struct v4l2_fmtdesc vfd
= { .type
= V4L2_BUF_TYPE_VIDEO_CAPTURE
};
273 while(!v4l2_ioctl(s
->fd
, VIDIOC_ENUM_FMT
, &vfd
)) {
274 enum AVCodecID codec_id
= ff_fmt_v4l2codec(vfd
.pixelformat
);
275 enum AVPixelFormat pix_fmt
= ff_fmt_v4l2ff(vfd
.pixelformat
, codec_id
);
279 if (!(vfd
.flags
& V4L2_FMT_FLAG_COMPRESSED
) &&
280 type
& V4L_RAWFORMATS
) {
281 const char *fmt_name
= av_get_pix_fmt_name(pix_fmt
);
282 av_log(ctx
, AV_LOG_INFO
, "Raw : %9s : %20s :",
283 fmt_name
? fmt_name
: "Unsupported",
285 } else if (vfd
.flags
& V4L2_FMT_FLAG_COMPRESSED
&&
286 type
& V4L_COMPFORMATS
) {
287 AVCodec
*codec
= avcodec_find_decoder(codec_id
);
288 av_log(ctx
, AV_LOG_INFO
, "Compressed: %9s : %20s :",
289 codec
? codec
->name
: "Unsupported",
295 #ifdef V4L2_FMT_FLAG_EMULATED
296 if (vfd
.flags
& V4L2_FMT_FLAG_EMULATED
)
297 av_log(ctx
, AV_LOG_INFO
, " Emulated :");
299 #if HAVE_STRUCT_V4L2_FRMIVALENUM_DISCRETE
300 list_framesizes(ctx
, vfd
.pixelformat
);
302 av_log(ctx
, AV_LOG_INFO
, "\n");
306 static void list_standards(AVFormatContext
*ctx
)
309 struct video_data
*s
= ctx
->priv_data
;
310 struct v4l2_standard standard
;
315 for (standard
.index
= 0; ; standard
.index
++) {
316 if (v4l2_ioctl(s
->fd
, VIDIOC_ENUMSTD
, &standard
) < 0) {
317 ret
= AVERROR(errno
);
318 if (ret
== AVERROR(EINVAL
)) {
321 av_log(ctx
, AV_LOG_ERROR
, "ioctl(VIDIOC_ENUMSTD): %s\n", av_err2str(ret
));
325 av_log(ctx
, AV_LOG_INFO
, "%2d, %16"PRIx64
", %s\n",
326 standard
.index
, (uint64_t)standard
.id
, standard
.name
);
330 static int mmap_init(AVFormatContext
*ctx
)
333 struct video_data
*s
= ctx
->priv_data
;
334 struct v4l2_requestbuffers req
= {
335 .type
= V4L2_BUF_TYPE_VIDEO_CAPTURE
,
336 .count
= desired_video_buffers
,
337 .memory
= V4L2_MEMORY_MMAP
340 if (v4l2_ioctl(s
->fd
, VIDIOC_REQBUFS
, &req
) < 0) {
341 res
= AVERROR(errno
);
342 av_log(ctx
, AV_LOG_ERROR
, "ioctl(VIDIOC_REQBUFS): %s\n", av_err2str(res
));
347 av_log(ctx
, AV_LOG_ERROR
, "Insufficient buffer memory\n");
348 return AVERROR(ENOMEM
);
350 s
->buffers
= req
.count
;
351 s
->buf_start
= av_malloc_array(s
->buffers
, sizeof(void *));
353 av_log(ctx
, AV_LOG_ERROR
, "Cannot allocate buffer pointers\n");
354 return AVERROR(ENOMEM
);
356 s
->buf_len
= av_malloc_array(s
->buffers
, sizeof(unsigned int));
358 av_log(ctx
, AV_LOG_ERROR
, "Cannot allocate buffer sizes\n");
359 av_free(s
->buf_start
);
360 return AVERROR(ENOMEM
);
363 for (i
= 0; i
< req
.count
; i
++) {
364 struct v4l2_buffer buf
= {
365 .type
= V4L2_BUF_TYPE_VIDEO_CAPTURE
,
367 .memory
= V4L2_MEMORY_MMAP
369 if (v4l2_ioctl(s
->fd
, VIDIOC_QUERYBUF
, &buf
) < 0) {
370 res
= AVERROR(errno
);
371 av_log(ctx
, AV_LOG_ERROR
, "ioctl(VIDIOC_QUERYBUF): %s\n", av_err2str(res
));
375 s
->buf_len
[i
] = buf
.length
;
376 if (s
->frame_size
> 0 && s
->buf_len
[i
] < s
->frame_size
) {
377 av_log(ctx
, AV_LOG_ERROR
,
378 "buf_len[%d] = %d < expected frame size %d\n",
379 i
, s
->buf_len
[i
], s
->frame_size
);
380 return AVERROR(ENOMEM
);
382 s
->buf_start
[i
] = v4l2_mmap(NULL
, buf
.length
,
383 PROT_READ
| PROT_WRITE
, MAP_SHARED
,
384 s
->fd
, buf
.m
.offset
);
386 if (s
->buf_start
[i
] == MAP_FAILED
) {
387 res
= AVERROR(errno
);
388 av_log(ctx
, AV_LOG_ERROR
, "mmap: %s\n", av_err2str(res
));
396 #if FF_API_DESTRUCT_PACKET
397 static void dummy_release_buffer(AVPacket
*pkt
)
403 static int enqueue_buffer(struct video_data
*s
, struct v4l2_buffer
*buf
)
407 if (v4l2_ioctl(s
->fd
, VIDIOC_QBUF
, buf
) < 0) {
408 res
= AVERROR(errno
);
409 av_log(NULL
, AV_LOG_ERROR
, "ioctl(VIDIOC_QBUF): %s\n", av_err2str(res
));
411 avpriv_atomic_int_add_and_fetch(&s
->buffers_queued
, 1);
417 static void mmap_release_buffer(void *opaque
, uint8_t *data
)
419 struct v4l2_buffer buf
= { 0 };
420 struct buff_data
*buf_descriptor
= opaque
;
421 struct video_data
*s
= buf_descriptor
->s
;
423 buf
.type
= V4L2_BUF_TYPE_VIDEO_CAPTURE
;
424 buf
.memory
= V4L2_MEMORY_MMAP
;
425 buf
.index
= buf_descriptor
->index
;
426 av_free(buf_descriptor
);
428 enqueue_buffer(s
, &buf
);
431 #if HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC)
432 static int64_t av_gettime_monotonic(void)
434 return av_gettime_relative();
438 static int init_convert_timestamp(AVFormatContext
*ctx
, int64_t ts
)
440 struct video_data
*s
= ctx
->priv_data
;
444 if (s
->ts_mode
== V4L_TS_ABS
&&
445 ts
<= now
+ 1 * AV_TIME_BASE
&& ts
>= now
- 10 * AV_TIME_BASE
) {
446 av_log(ctx
, AV_LOG_INFO
, "Detected absolute timestamps\n");
447 s
->ts_mode
= V4L_TS_CONVERT_READY
;
450 #if HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC)
451 if (ctx
->streams
[0]->avg_frame_rate
.num
) {
452 now
= av_gettime_monotonic();
453 if (s
->ts_mode
== V4L_TS_MONO2ABS
||
454 (ts
<= now
+ 1 * AV_TIME_BASE
&& ts
>= now
- 10 * AV_TIME_BASE
)) {
455 AVRational tb
= {AV_TIME_BASE
, 1};
456 int64_t period
= av_rescale_q(1, tb
, ctx
->streams
[0]->avg_frame_rate
);
457 av_log(ctx
, AV_LOG_INFO
, "Detected monotonic timestamps, converting\n");
458 /* microseconds instead of seconds, MHz instead of Hz */
459 s
->timefilter
= ff_timefilter_new(1, period
, 1.0E-6);
461 return AVERROR(ENOMEM
);
462 s
->ts_mode
= V4L_TS_CONVERT_READY
;
467 av_log(ctx
, AV_LOG_ERROR
, "Unknown timestamps\n");
471 static int convert_timestamp(AVFormatContext
*ctx
, int64_t *ts
)
473 struct video_data
*s
= ctx
->priv_data
;
476 int r
= init_convert_timestamp(ctx
, *ts
);
480 #if HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC)
482 int64_t nowa
= av_gettime();
483 int64_t nowm
= av_gettime_monotonic();
484 ff_timefilter_update(s
->timefilter
, nowa
, nowm
- s
->last_time_m
);
485 s
->last_time_m
= nowm
;
486 *ts
= ff_timefilter_eval(s
->timefilter
, *ts
- nowm
);
492 static int mmap_read_frame(AVFormatContext
*ctx
, AVPacket
*pkt
)
494 struct video_data
*s
= ctx
->priv_data
;
495 struct v4l2_buffer buf
= {
496 .type
= V4L2_BUF_TYPE_VIDEO_CAPTURE
,
497 .memory
= V4L2_MEMORY_MMAP
501 /* FIXME: Some special treatment might be needed in case of loss of signal... */
502 while ((res
= v4l2_ioctl(s
->fd
, VIDIOC_DQBUF
, &buf
)) < 0 && (errno
== EINTR
));
504 if (errno
== EAGAIN
) {
506 return AVERROR(EAGAIN
);
508 res
= AVERROR(errno
);
509 av_log(ctx
, AV_LOG_ERROR
, "ioctl(VIDIOC_DQBUF): %s\n",
514 if (buf
.index
>= s
->buffers
) {
515 av_log(ctx
, AV_LOG_ERROR
, "Invalid buffer index received.\n");
516 return AVERROR(EINVAL
);
518 avpriv_atomic_int_add_and_fetch(&s
->buffers_queued
, -1);
519 // always keep at least one buffer queued
520 av_assert0(avpriv_atomic_int_get(&s
->buffers_queued
) >= 1);
522 /* CPIA is a compressed format and we don't know the exact number of bytes
523 * used by a frame, so set it here as the driver announces it.
525 if (ctx
->video_codec_id
== AV_CODEC_ID_CPIA
)
526 s
->frame_size
= buf
.bytesused
;
528 if (s
->frame_size
> 0 && buf
.bytesused
!= s
->frame_size
) {
529 av_log(ctx
, AV_LOG_ERROR
,
530 "The v4l2 frame is %d bytes, but %d bytes are expected\n",
531 buf
.bytesused
, s
->frame_size
);
532 enqueue_buffer(s
, &buf
);
533 return AVERROR_INVALIDDATA
;
536 /* Image is at s->buff_start[buf.index] */
537 if (avpriv_atomic_int_get(&s
->buffers_queued
) == FFMAX(s
->buffers
/ 8, 1)) {
538 /* when we start getting low on queued buffers, fall back on copying data */
539 res
= av_new_packet(pkt
, buf
.bytesused
);
541 av_log(ctx
, AV_LOG_ERROR
, "Error allocating a packet.\n");
542 enqueue_buffer(s
, &buf
);
545 memcpy(pkt
->data
, s
->buf_start
[buf
.index
], buf
.bytesused
);
547 res
= enqueue_buffer(s
, &buf
);
553 struct buff_data
*buf_descriptor
;
555 pkt
->data
= s
->buf_start
[buf
.index
];
556 pkt
->size
= buf
.bytesused
;
557 #if FF_API_DESTRUCT_PACKET
558 FF_DISABLE_DEPRECATION_WARNINGS
559 pkt
->destruct
= dummy_release_buffer
;
560 FF_ENABLE_DEPRECATION_WARNINGS
563 buf_descriptor
= av_malloc(sizeof(struct buff_data
));
564 if (!buf_descriptor
) {
565 /* Something went wrong... Since av_malloc() failed, we cannot even
566 * allocate a buffer for memcpying into it
568 av_log(ctx
, AV_LOG_ERROR
, "Failed to allocate a buffer descriptor\n");
569 enqueue_buffer(s
, &buf
);
571 return AVERROR(ENOMEM
);
573 buf_descriptor
->index
= buf
.index
;
574 buf_descriptor
->s
= s
;
576 pkt
->buf
= av_buffer_create(pkt
->data
, pkt
->size
, mmap_release_buffer
,
579 av_log(ctx
, AV_LOG_ERROR
, "Failed to create a buffer\n");
580 enqueue_buffer(s
, &buf
);
581 av_freep(&buf_descriptor
);
582 return AVERROR(ENOMEM
);
585 pkt
->pts
= buf
.timestamp
.tv_sec
* INT64_C(1000000) + buf
.timestamp
.tv_usec
;
586 convert_timestamp(ctx
, &pkt
->pts
);
588 return s
->buf_len
[buf
.index
];
591 static int mmap_start(AVFormatContext
*ctx
)
593 struct video_data
*s
= ctx
->priv_data
;
594 enum v4l2_buf_type type
;
597 for (i
= 0; i
< s
->buffers
; i
++) {
598 struct v4l2_buffer buf
= {
599 .type
= V4L2_BUF_TYPE_VIDEO_CAPTURE
,
601 .memory
= V4L2_MEMORY_MMAP
604 if (v4l2_ioctl(s
->fd
, VIDIOC_QBUF
, &buf
) < 0) {
605 res
= AVERROR(errno
);
606 av_log(ctx
, AV_LOG_ERROR
, "ioctl(VIDIOC_QBUF): %s\n",
611 s
->buffers_queued
= s
->buffers
;
613 type
= V4L2_BUF_TYPE_VIDEO_CAPTURE
;
614 if (v4l2_ioctl(s
->fd
, VIDIOC_STREAMON
, &type
) < 0) {
615 res
= AVERROR(errno
);
616 av_log(ctx
, AV_LOG_ERROR
, "ioctl(VIDIOC_STREAMON): %s\n",
624 static void mmap_close(struct video_data
*s
)
626 enum v4l2_buf_type type
;
629 type
= V4L2_BUF_TYPE_VIDEO_CAPTURE
;
630 /* We do not check for the result, because we could
631 * not do anything about it anyway...
633 v4l2_ioctl(s
->fd
, VIDIOC_STREAMOFF
, &type
);
634 for (i
= 0; i
< s
->buffers
; i
++) {
635 v4l2_munmap(s
->buf_start
[i
], s
->buf_len
[i
]);
637 av_free(s
->buf_start
);
641 static int v4l2_set_parameters(AVFormatContext
*ctx
)
643 struct video_data
*s
= ctx
->priv_data
;
644 struct v4l2_standard standard
= { 0 };
645 struct v4l2_streamparm streamparm
= { 0 };
646 struct v4l2_fract
*tpf
;
647 AVRational framerate_q
= { 0 };
651 (ret
= av_parse_video_rate(&framerate_q
, s
->framerate
)) < 0) {
652 av_log(ctx
, AV_LOG_ERROR
, "Could not parse framerate '%s'.\n",
660 av_log(ctx
, AV_LOG_DEBUG
, "Setting standard: %s\n", s
->standard
);
661 /* set tv standard */
664 if (v4l2_ioctl(s
->fd
, VIDIOC_ENUMSTD
, &standard
) < 0) {
665 ret
= AVERROR(errno
);
668 if (!av_strcasecmp(standard
.name
, s
->standard
))
672 av_log(ctx
, AV_LOG_ERROR
, "Unknown or unsupported standard '%s'\n", s
->standard
);
676 if (v4l2_ioctl(s
->fd
, VIDIOC_S_STD
, &standard
.id
) < 0) {
677 ret
= AVERROR(errno
);
678 av_log(ctx
, AV_LOG_ERROR
, "ioctl(VIDIOC_S_STD): %s\n", av_err2str(ret
));
682 av_log(ctx
, AV_LOG_WARNING
,
683 "This device does not support any standard\n");
688 if (v4l2_ioctl(s
->fd
, VIDIOC_G_STD
, &s
->std_id
) == 0) {
689 tpf
= &standard
.frameperiod
;
692 if (v4l2_ioctl(s
->fd
, VIDIOC_ENUMSTD
, &standard
) < 0) {
693 ret
= AVERROR(errno
);
694 if (ret
== AVERROR(EINVAL
)
696 || ret
== AVERROR(ENODATA
)
699 tpf
= &streamparm
.parm
.capture
.timeperframe
;
702 av_log(ctx
, AV_LOG_ERROR
, "ioctl(VIDIOC_ENUMSTD): %s\n", av_err2str(ret
));
705 if (standard
.id
== s
->std_id
) {
706 av_log(ctx
, AV_LOG_DEBUG
,
707 "Current standard: %s, id: %"PRIx64
", frameperiod: %d/%d\n",
708 standard
.name
, (uint64_t)standard
.id
, tpf
->numerator
, tpf
->denominator
);
713 tpf
= &streamparm
.parm
.capture
.timeperframe
;
716 streamparm
.type
= V4L2_BUF_TYPE_VIDEO_CAPTURE
;
717 if (v4l2_ioctl(s
->fd
, VIDIOC_G_PARM
, &streamparm
) < 0) {
718 ret
= AVERROR(errno
);
719 av_log(ctx
, AV_LOG_ERROR
, "ioctl(VIDIOC_G_PARM): %s\n", av_err2str(ret
));
723 if (framerate_q
.num
&& framerate_q
.den
) {
724 if (streamparm
.parm
.capture
.capability
& V4L2_CAP_TIMEPERFRAME
) {
725 tpf
= &streamparm
.parm
.capture
.timeperframe
;
727 av_log(ctx
, AV_LOG_DEBUG
, "Setting time per frame to %d/%d\n",
728 framerate_q
.den
, framerate_q
.num
);
729 tpf
->numerator
= framerate_q
.den
;
730 tpf
->denominator
= framerate_q
.num
;
732 if (v4l2_ioctl(s
->fd
, VIDIOC_S_PARM
, &streamparm
) < 0) {
733 ret
= AVERROR(errno
);
734 av_log(ctx
, AV_LOG_ERROR
, "ioctl(VIDIOC_S_PARM): %s\n",
739 if (framerate_q
.num
!= tpf
->denominator
||
740 framerate_q
.den
!= tpf
->numerator
) {
741 av_log(ctx
, AV_LOG_INFO
,
742 "The driver changed the time per frame from "
744 framerate_q
.den
, framerate_q
.num
,
745 tpf
->numerator
, tpf
->denominator
);
748 av_log(ctx
, AV_LOG_WARNING
,
749 "The driver does not allow to change time per frame\n");
752 if (tpf
->denominator
> 0 && tpf
->numerator
> 0) {
753 ctx
->streams
[0]->avg_frame_rate
.num
= tpf
->denominator
;
754 ctx
->streams
[0]->avg_frame_rate
.den
= tpf
->numerator
;
755 ctx
->streams
[0]->r_frame_rate
= ctx
->streams
[0]->avg_frame_rate
;
757 av_log(ctx
, AV_LOG_WARNING
, "Time per frame unknown\n");
762 static int device_try_init(AVFormatContext
*ctx
,
763 enum AVPixelFormat pix_fmt
,
766 uint32_t *desired_format
,
767 enum AVCodecID
*codec_id
)
771 *desired_format
= ff_fmt_ff2v4l(pix_fmt
, ctx
->video_codec_id
);
773 if (*desired_format
) {
774 ret
= device_init(ctx
, width
, height
, *desired_format
);
777 if (ret
!= AVERROR(EINVAL
))
782 if (!*desired_format
) {
783 for (i
= 0; ff_fmt_conversion_table
[i
].codec_id
!= AV_CODEC_ID_NONE
; i
++) {
784 if (ctx
->video_codec_id
== AV_CODEC_ID_NONE
||
785 ff_fmt_conversion_table
[i
].codec_id
== ctx
->video_codec_id
) {
786 av_log(ctx
, AV_LOG_DEBUG
, "Trying to set codec:%s pix_fmt:%s\n",
787 avcodec_get_name(ff_fmt_conversion_table
[i
].codec_id
),
788 (char *)av_x_if_null(av_get_pix_fmt_name(ff_fmt_conversion_table
[i
].ff_fmt
), "none"));
790 *desired_format
= ff_fmt_conversion_table
[i
].v4l2_fmt
;
791 ret
= device_init(ctx
, width
, height
, *desired_format
);
794 else if (ret
!= AVERROR(EINVAL
))
800 if (*desired_format
== 0) {
801 av_log(ctx
, AV_LOG_ERROR
, "Cannot find a proper format for "
802 "codec '%s' (id %d), pixel format '%s' (id %d)\n",
803 avcodec_get_name(ctx
->video_codec_id
), ctx
->video_codec_id
,
804 (char *)av_x_if_null(av_get_pix_fmt_name(pix_fmt
), "none"), pix_fmt
);
805 ret
= AVERROR(EINVAL
);
809 *codec_id
= ff_fmt_v4l2codec(*desired_format
);
810 av_assert0(*codec_id
!= AV_CODEC_ID_NONE
);
814 static int v4l2_read_probe(AVProbeData
*p
)
816 if (av_strstart(p
->filename
, "/dev/video", NULL
))
817 return AVPROBE_SCORE_MAX
- 1;
821 static int v4l2_read_header(AVFormatContext
*ctx
)
823 struct video_data
*s
= ctx
->priv_data
;
826 uint32_t desired_format
;
827 enum AVCodecID codec_id
= AV_CODEC_ID_NONE
;
828 enum AVPixelFormat pix_fmt
= AV_PIX_FMT_NONE
;
829 struct v4l2_input input
= { 0 };
831 st
= avformat_new_stream(ctx
, NULL
);
833 return AVERROR(ENOMEM
);
836 /* silence libv4l2 logging. if fopen() fails v4l2_log_file will be NULL
837 and errors will get sent to stderr */
839 v4l2_log_file
= fopen("/dev/null", "w");
842 s
->fd
= device_open(ctx
);
846 if (s
->channel
!= -1) {
847 /* set video input */
848 av_log(ctx
, AV_LOG_DEBUG
, "Selecting input_channel: %d\n", s
->channel
);
849 if (v4l2_ioctl(s
->fd
, VIDIOC_S_INPUT
, &s
->channel
) < 0) {
850 res
= AVERROR(errno
);
851 av_log(ctx
, AV_LOG_ERROR
, "ioctl(VIDIOC_S_INPUT): %s\n", av_err2str(res
));
855 /* get current video input */
856 if (v4l2_ioctl(s
->fd
, VIDIOC_G_INPUT
, &s
->channel
) < 0) {
857 res
= AVERROR(errno
);
858 av_log(ctx
, AV_LOG_ERROR
, "ioctl(VIDIOC_G_INPUT): %s\n", av_err2str(res
));
864 input
.index
= s
->channel
;
865 if (v4l2_ioctl(s
->fd
, VIDIOC_ENUMINPUT
, &input
) < 0) {
866 res
= AVERROR(errno
);
867 av_log(ctx
, AV_LOG_ERROR
, "ioctl(VIDIOC_ENUMINPUT): %s\n", av_err2str(res
));
870 s
->std_id
= input
.std
;
871 av_log(ctx
, AV_LOG_DEBUG
, "Current input_channel: %d, input_name: %s, input_std: %"PRIx64
"\n",
872 s
->channel
, input
.name
, (uint64_t)input
.std
);
874 if (s
->list_format
) {
875 list_formats(ctx
, s
->list_format
);
880 if (s
->list_standard
) {
886 avpriv_set_pts_info(st
, 64, 1, 1000000); /* 64 bits pts in us */
888 if (s
->pixel_format
) {
889 AVCodec
*codec
= avcodec_find_decoder_by_name(s
->pixel_format
);
892 ctx
->video_codec_id
= codec
->id
;
894 pix_fmt
= av_get_pix_fmt(s
->pixel_format
);
896 if (pix_fmt
== AV_PIX_FMT_NONE
&& !codec
) {
897 av_log(ctx
, AV_LOG_ERROR
, "No such input format: %s.\n",
900 res
= AVERROR(EINVAL
);
905 if (!s
->width
&& !s
->height
) {
906 struct v4l2_format fmt
= { .type
= V4L2_BUF_TYPE_VIDEO_CAPTURE
};
908 av_log(ctx
, AV_LOG_VERBOSE
,
909 "Querying the device for the current frame size\n");
910 if (v4l2_ioctl(s
->fd
, VIDIOC_G_FMT
, &fmt
) < 0) {
911 res
= AVERROR(errno
);
912 av_log(ctx
, AV_LOG_ERROR
, "ioctl(VIDIOC_G_FMT): %s\n",
917 s
->width
= fmt
.fmt
.pix
.width
;
918 s
->height
= fmt
.fmt
.pix
.height
;
919 av_log(ctx
, AV_LOG_VERBOSE
,
920 "Setting frame size to %dx%d\n", s
->width
, s
->height
);
923 res
= device_try_init(ctx
, pix_fmt
, &s
->width
, &s
->height
, &desired_format
, &codec_id
);
927 /* If no pixel_format was specified, the codec_id was not known up
928 * until now. Set video_codec_id in the context, as codec_id will
929 * not be available outside this function
931 if (codec_id
!= AV_CODEC_ID_NONE
&& ctx
->video_codec_id
== AV_CODEC_ID_NONE
)
932 ctx
->video_codec_id
= codec_id
;
934 if ((res
= av_image_check_size(s
->width
, s
->height
, 0, ctx
)) < 0)
937 s
->pixelformat
= desired_format
;
939 if ((res
= v4l2_set_parameters(ctx
)) < 0)
942 st
->codec
->pix_fmt
= ff_fmt_v4l2ff(desired_format
, codec_id
);
944 avpicture_get_size(st
->codec
->pix_fmt
, s
->width
, s
->height
);
946 if ((res
= mmap_init(ctx
)) ||
947 (res
= mmap_start(ctx
)) < 0)
950 s
->top_field_first
= first_field(s
);
952 st
->codec
->codec_type
= AVMEDIA_TYPE_VIDEO
;
953 st
->codec
->codec_id
= codec_id
;
954 if (codec_id
== AV_CODEC_ID_RAWVIDEO
)
955 st
->codec
->codec_tag
=
956 avcodec_pix_fmt_to_codec_tag(st
->codec
->pix_fmt
);
957 else if (codec_id
== AV_CODEC_ID_H264
) {
958 st
->need_parsing
= AVSTREAM_PARSE_HEADERS
;
960 if (desired_format
== V4L2_PIX_FMT_YVU420
)
961 st
->codec
->codec_tag
= MKTAG('Y', 'V', '1', '2');
962 else if (desired_format
== V4L2_PIX_FMT_YVU410
)
963 st
->codec
->codec_tag
= MKTAG('Y', 'V', 'U', '9');
964 st
->codec
->width
= s
->width
;
965 st
->codec
->height
= s
->height
;
966 if (st
->avg_frame_rate
.den
)
967 st
->codec
->bit_rate
= s
->frame_size
* av_q2d(st
->avg_frame_rate
) * 8;
976 static int v4l2_read_packet(AVFormatContext
*ctx
, AVPacket
*pkt
)
978 struct video_data
*s
= ctx
->priv_data
;
979 AVFrame
*frame
= ctx
->streams
[0]->codec
->coded_frame
;
983 if ((res
= mmap_read_frame(ctx
, pkt
)) < 0) {
987 if (frame
&& s
->interlaced
) {
988 frame
->interlaced_frame
= 1;
989 frame
->top_field_first
= s
->top_field_first
;
995 static int v4l2_read_close(AVFormatContext
*ctx
)
997 struct video_data
*s
= ctx
->priv_data
;
999 if (avpriv_atomic_int_get(&s
->buffers_queued
) != s
->buffers
)
1000 av_log(ctx
, AV_LOG_WARNING
, "Some buffers are still owned by the caller on "
1009 #define OFFSET(x) offsetof(struct video_data, x)
1010 #define DEC AV_OPT_FLAG_DECODING_PARAM
1012 static const AVOption options
[] = {
1013 { "standard", "set TV standard, used only by analog frame grabber", OFFSET(standard
), AV_OPT_TYPE_STRING
, {.str
= NULL
}, 0, 0, DEC
},
1014 { "channel", "set TV channel, used only by frame grabber", OFFSET(channel
), AV_OPT_TYPE_INT
, {.i64
= -1 }, -1, INT_MAX
, DEC
},
1015 { "video_size", "set frame size", OFFSET(width
), AV_OPT_TYPE_IMAGE_SIZE
, {.str
= NULL
}, 0, 0, DEC
},
1016 { "pixel_format", "set preferred pixel format", OFFSET(pixel_format
), AV_OPT_TYPE_STRING
, {.str
= NULL
}, 0, 0, DEC
},
1017 { "input_format", "set preferred pixel format (for raw video) or codec name", OFFSET(pixel_format
), AV_OPT_TYPE_STRING
, {.str
= NULL
}, 0, 0, DEC
},
1018 { "framerate", "set frame rate", OFFSET(framerate
), AV_OPT_TYPE_STRING
, {.str
= NULL
}, 0, 0, DEC
},
1020 { "list_formats", "list available formats and exit", OFFSET(list_format
), AV_OPT_TYPE_INT
, {.i64
= 0 }, 0, INT_MAX
, DEC
, "list_formats" },
1021 { "all", "show all available formats", OFFSET(list_format
), AV_OPT_TYPE_CONST
, {.i64
= V4L_ALLFORMATS
}, 0, INT_MAX
, DEC
, "list_formats" },
1022 { "raw", "show only non-compressed formats", OFFSET(list_format
), AV_OPT_TYPE_CONST
, {.i64
= V4L_RAWFORMATS
}, 0, INT_MAX
, DEC
, "list_formats" },
1023 { "compressed", "show only compressed formats", OFFSET(list_format
), AV_OPT_TYPE_CONST
, {.i64
= V4L_COMPFORMATS
}, 0, INT_MAX
, DEC
, "list_formats" },
1025 { "list_standards", "list supported standards and exit", OFFSET(list_standard
), AV_OPT_TYPE_INT
, {.i64
= 0 }, 0, 1, DEC
, "list_standards" },
1026 { "all", "show all supported standards", OFFSET(list_standard
), AV_OPT_TYPE_CONST
, {.i64
= 1 }, 0, 0, DEC
, "list_standards" },
1028 { "timestamps", "set type of timestamps for grabbed frames", OFFSET(ts_mode
), AV_OPT_TYPE_INT
, {.i64
= 0 }, 0, 2, DEC
, "timestamps" },
1029 { "ts", "set type of timestamps for grabbed frames", OFFSET(ts_mode
), AV_OPT_TYPE_INT
, {.i64
= 0 }, 0, 2, DEC
, "timestamps" },
1030 { "default", "use timestamps from the kernel", OFFSET(ts_mode
), AV_OPT_TYPE_CONST
, {.i64
= V4L_TS_DEFAULT
}, 0, 2, DEC
, "timestamps" },
1031 { "abs", "use absolute timestamps (wall clock)", OFFSET(ts_mode
), AV_OPT_TYPE_CONST
, {.i64
= V4L_TS_ABS
}, 0, 2, DEC
, "timestamps" },
1032 { "mono2abs", "force conversion from monotonic to absolute timestamps", OFFSET(ts_mode
), AV_OPT_TYPE_CONST
, {.i64
= V4L_TS_MONO2ABS
}, 0, 2, DEC
, "timestamps" },
1033 { "use_libv4l2", "use libv4l2 (v4l-utils) conversion functions", OFFSET(use_libv4l2
), AV_OPT_TYPE_INT
, {.i64
= 0}, 0, 1, DEC
},
1037 static const AVClass v4l2_class
= {
1038 .class_name
= "V4L2 indev",
1039 .item_name
= av_default_item_name
,
1041 .version
= LIBAVUTIL_VERSION_INT
,
1042 .category
= AV_CLASS_CATEGORY_DEVICE_VIDEO_INPUT
,
1045 AVInputFormat ff_v4l2_demuxer
= {
1046 .name
= "video4linux2,v4l2",
1047 .long_name
= NULL_IF_CONFIG_SMALL("Video4Linux2 device grab"),
1048 .priv_data_size
= sizeof(struct video_data
),
1049 .read_probe
= v4l2_read_probe
,
1050 .read_header
= v4l2_read_header
,
1051 .read_packet
= v4l2_read_packet
,
1052 .read_close
= v4l2_read_close
,
1053 .flags
= AVFMT_NOFILE
,
1054 .priv_class
= &v4l2_class
,