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 #undef __STRICT_ANSI__ //workaround due to broken kernel headers
35 #include "libavformat/internal.h"
38 #include <sys/ioctl.h>
41 #if HAVE_SYS_VIDEOIO_H
42 #include <sys/videoio.h>
45 #include <asm/types.h>
47 #include <linux/videodev2.h>
49 #include "libavutil/avassert.h"
50 #include "libavutil/imgutils.h"
51 #include "libavutil/log.h"
52 #include "libavutil/opt.h"
54 #include "timefilter.h"
55 #include "libavutil/parseutils.h"
56 #include "libavutil/pixdesc.h"
57 #include "libavutil/avstring.h"
62 #define v4l2_open open
63 #define v4l2_close close
65 #define v4l2_ioctl ioctl
66 #define v4l2_read read
67 #define v4l2_mmap mmap
68 #define v4l2_munmap munmap
71 static const int desired_video_buffers = 256;
73 #define V4L_ALLFORMATS 3
74 #define V4L_RAWFORMATS 1
75 #define V4L_COMPFORMATS 2
78 * Return timestamps to the user exactly as returned by the kernel
80 #define V4L_TS_DEFAULT 0
82 * Autodetect the kind of timestamps returned by the kernel and convert to
83 * absolute (wall clock) timestamps.
87 * Assume kernel timestamps are from the monotonic clock and convert to
88 * absolute timestamps.
90 #define V4L_TS_MONO2ABS 2
93 * Once the kind of timestamps returned by the kernel have been detected,
94 * the value of the timefilter (NULL or not) determines whether a conversion
97 #define V4L_TS_CONVERT_READY V4L_TS_DEFAULT
102 int frame_format; /* V4L2_PIX_FMT_* */
108 TimeFilter *timefilter;
113 unsigned int *buf_len;
116 char *pixel_format; /**< Set by a private option. */
117 int list_format; /**< Set by a private option. */
118 char *framerate; /**< Set by a private option. */
127 enum AVPixelFormat ff_fmt;
128 enum AVCodecID codec_id;
132 static struct fmt_map fmt_conversion_table[] = {
133 //ff_fmt codec_id v4l2_fmt
134 { AV_PIX_FMT_YUV420P, AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_YUV420 },
135 { AV_PIX_FMT_YUV420P, AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_YVU420 },
136 { AV_PIX_FMT_YUV422P, AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_YUV422P },
137 { AV_PIX_FMT_YUYV422, AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_YUYV },
138 { AV_PIX_FMT_UYVY422, AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_UYVY },
139 { AV_PIX_FMT_YUV411P, AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_YUV411P },
140 { AV_PIX_FMT_YUV410P, AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_YUV410 },
141 { AV_PIX_FMT_RGB555LE,AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_RGB555 },
142 { AV_PIX_FMT_RGB555BE,AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_RGB555X },
143 { AV_PIX_FMT_RGB565LE,AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_RGB565 },
144 { AV_PIX_FMT_RGB565BE,AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_RGB565X },
145 { AV_PIX_FMT_BGR24, AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_BGR24 },
146 { AV_PIX_FMT_RGB24, AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_RGB24 },
147 { AV_PIX_FMT_BGR0, AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_BGR32 },
148 { AV_PIX_FMT_0RGB, AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_RGB32 },
149 { AV_PIX_FMT_GRAY8, AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_GREY },
150 { AV_PIX_FMT_NV12, AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_NV12 },
151 { AV_PIX_FMT_NONE, AV_CODEC_ID_MJPEG, V4L2_PIX_FMT_MJPEG },
152 { AV_PIX_FMT_NONE, AV_CODEC_ID_MJPEG, V4L2_PIX_FMT_JPEG },
153 #ifdef V4L2_PIX_FMT_H264
154 { AV_PIX_FMT_NONE, AV_CODEC_ID_H264, V4L2_PIX_FMT_H264 },
156 #ifdef V4L2_PIX_FMT_CPIA1
157 { AV_PIX_FMT_NONE, AV_CODEC_ID_CPIA, V4L2_PIX_FMT_CPIA1 },
161 static int device_open(AVFormatContext *ctx)
163 struct v4l2_capability cap;
168 if (ctx->flags & AVFMT_FLAG_NONBLOCK) {
172 fd = v4l2_open(ctx->filename, flags, 0);
176 av_log(ctx, AV_LOG_ERROR, "Cannot open video device %s: %s\n",
177 ctx->filename, strerror(err));
182 res = v4l2_ioctl(fd, VIDIOC_QUERYCAP, &cap);
185 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYCAP): %s\n",
191 av_log(ctx, AV_LOG_VERBOSE, "fd:%d capabilities:%x\n",
192 fd, cap.capabilities);
194 if (!(cap.capabilities & V4L2_CAP_VIDEO_CAPTURE)) {
195 av_log(ctx, AV_LOG_ERROR, "Not a video capture device.\n");
201 if (!(cap.capabilities & V4L2_CAP_STREAMING)) {
202 av_log(ctx, AV_LOG_ERROR,
203 "The device does not support the streaming I/O method.\n");
216 static int device_init(AVFormatContext *ctx, int *width, int *height,
219 struct video_data *s = ctx->priv_data;
221 struct v4l2_format fmt = { .type = V4L2_BUF_TYPE_VIDEO_CAPTURE };
222 struct v4l2_pix_format *pix = &fmt.fmt.pix;
227 pix->height = *height;
228 pix->pixelformat = pix_fmt;
229 pix->field = V4L2_FIELD_ANY;
231 if (v4l2_ioctl(fd, VIDIOC_S_FMT, &fmt) < 0)
232 res = AVERROR(errno);
234 if ((*width != fmt.fmt.pix.width) || (*height != fmt.fmt.pix.height)) {
235 av_log(ctx, AV_LOG_INFO,
236 "The V4L2 driver changed the video from %dx%d to %dx%d\n",
237 *width, *height, fmt.fmt.pix.width, fmt.fmt.pix.height);
238 *width = fmt.fmt.pix.width;
239 *height = fmt.fmt.pix.height;
242 if (pix_fmt != fmt.fmt.pix.pixelformat) {
243 av_log(ctx, AV_LOG_DEBUG,
244 "The V4L2 driver changed the pixel format "
245 "from 0x%08X to 0x%08X\n",
246 pix_fmt, fmt.fmt.pix.pixelformat);
247 res = AVERROR(EINVAL);
250 if (fmt.fmt.pix.field == V4L2_FIELD_INTERLACED) {
251 av_log(ctx, AV_LOG_DEBUG,
252 "The V4L2 driver is using the interlaced mode\n");
259 static int first_field(int fd)
264 res = v4l2_ioctl(fd, VIDIOC_G_STD, &std);
268 if (std & V4L2_STD_NTSC) {
275 static uint32_t fmt_ff2v4l(enum AVPixelFormat pix_fmt, enum AVCodecID codec_id)
279 for (i = 0; i < FF_ARRAY_ELEMS(fmt_conversion_table); i++) {
280 if ((codec_id == AV_CODEC_ID_NONE ||
281 fmt_conversion_table[i].codec_id == codec_id) &&
282 (pix_fmt == AV_PIX_FMT_NONE ||
283 fmt_conversion_table[i].ff_fmt == pix_fmt)) {
284 return fmt_conversion_table[i].v4l2_fmt;
291 static enum AVPixelFormat fmt_v4l2ff(uint32_t v4l2_fmt, enum AVCodecID codec_id)
295 for (i = 0; i < FF_ARRAY_ELEMS(fmt_conversion_table); i++) {
296 if (fmt_conversion_table[i].v4l2_fmt == v4l2_fmt &&
297 fmt_conversion_table[i].codec_id == codec_id) {
298 return fmt_conversion_table[i].ff_fmt;
302 return AV_PIX_FMT_NONE;
305 static enum AVCodecID fmt_v4l2codec(uint32_t v4l2_fmt)
309 for (i = 0; i < FF_ARRAY_ELEMS(fmt_conversion_table); i++) {
310 if (fmt_conversion_table[i].v4l2_fmt == v4l2_fmt) {
311 return fmt_conversion_table[i].codec_id;
315 return AV_CODEC_ID_NONE;
318 #if HAVE_STRUCT_V4L2_FRMIVALENUM_DISCRETE
319 static void list_framesizes(AVFormatContext *ctx, int fd, uint32_t pixelformat)
321 struct v4l2_frmsizeenum vfse = { .pixel_format = pixelformat };
323 while(!ioctl(fd, VIDIOC_ENUM_FRAMESIZES, &vfse)) {
325 case V4L2_FRMSIZE_TYPE_DISCRETE:
326 av_log(ctx, AV_LOG_INFO, " %ux%u",
327 vfse.discrete.width, vfse.discrete.height);
329 case V4L2_FRMSIZE_TYPE_CONTINUOUS:
330 case V4L2_FRMSIZE_TYPE_STEPWISE:
331 av_log(ctx, AV_LOG_INFO, " {%u-%u, %u}x{%u-%u, %u}",
332 vfse.stepwise.min_width,
333 vfse.stepwise.max_width,
334 vfse.stepwise.step_width,
335 vfse.stepwise.min_height,
336 vfse.stepwise.max_height,
337 vfse.stepwise.step_height);
344 static void list_formats(AVFormatContext *ctx, int fd, int type)
346 struct v4l2_fmtdesc vfd = { .type = V4L2_BUF_TYPE_VIDEO_CAPTURE };
348 while(!ioctl(fd, VIDIOC_ENUM_FMT, &vfd)) {
349 enum AVCodecID codec_id = fmt_v4l2codec(vfd.pixelformat);
350 enum AVPixelFormat pix_fmt = fmt_v4l2ff(vfd.pixelformat, codec_id);
354 if (!(vfd.flags & V4L2_FMT_FLAG_COMPRESSED) &&
355 type & V4L_RAWFORMATS) {
356 const char *fmt_name = av_get_pix_fmt_name(pix_fmt);
357 av_log(ctx, AV_LOG_INFO, "Raw : %9s : %20s :",
358 fmt_name ? fmt_name : "Unsupported",
360 } else if (vfd.flags & V4L2_FMT_FLAG_COMPRESSED &&
361 type & V4L_COMPFORMATS) {
362 AVCodec *codec = avcodec_find_encoder(codec_id);
363 av_log(ctx, AV_LOG_INFO, "Compressed: %9s : %20s :",
364 codec ? codec->name : "Unsupported",
370 #ifdef V4L2_FMT_FLAG_EMULATED
371 if (vfd.flags & V4L2_FMT_FLAG_EMULATED) {
372 av_log(ctx, AV_LOG_WARNING, "%s", "Emulated");
376 #if HAVE_STRUCT_V4L2_FRMIVALENUM_DISCRETE
377 list_framesizes(ctx, fd, vfd.pixelformat);
379 av_log(ctx, AV_LOG_INFO, "\n");
383 static int mmap_init(AVFormatContext *ctx)
386 struct video_data *s = ctx->priv_data;
387 struct v4l2_requestbuffers req = {
388 .type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
389 .count = desired_video_buffers,
390 .memory = V4L2_MEMORY_MMAP
393 res = v4l2_ioctl(s->fd, VIDIOC_REQBUFS, &req);
395 if (errno == EINVAL) {
396 av_log(ctx, AV_LOG_ERROR, "Device does not support mmap\n");
398 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_REQBUFS)\n");
400 return AVERROR(errno);
404 av_log(ctx, AV_LOG_ERROR, "Insufficient buffer memory\n");
405 return AVERROR(ENOMEM);
407 s->buffers = req.count;
408 s->buf_start = av_malloc(sizeof(void *) * s->buffers);
409 if (s->buf_start == NULL) {
410 av_log(ctx, AV_LOG_ERROR, "Cannot allocate buffer pointers\n");
411 return AVERROR(ENOMEM);
413 s->buf_len = av_malloc(sizeof(unsigned int) * s->buffers);
414 if (s->buf_len == NULL) {
415 av_log(ctx, AV_LOG_ERROR, "Cannot allocate buffer sizes\n");
416 av_free(s->buf_start);
417 return AVERROR(ENOMEM);
420 for (i = 0; i < req.count; i++) {
421 struct v4l2_buffer buf = {
422 .type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
424 .memory = V4L2_MEMORY_MMAP
426 res = v4l2_ioctl(s->fd, VIDIOC_QUERYBUF, &buf);
428 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYBUF)\n");
429 return AVERROR(errno);
432 s->buf_len[i] = buf.length;
433 if (s->frame_size > 0 && s->buf_len[i] < s->frame_size) {
434 av_log(ctx, AV_LOG_ERROR,
435 "Buffer len [%d] = %d != %d\n",
436 i, s->buf_len[i], s->frame_size);
440 s->buf_start[i] = v4l2_mmap(NULL, buf.length,
441 PROT_READ | PROT_WRITE, MAP_SHARED,
442 s->fd, buf.m.offset);
444 if (s->buf_start[i] == MAP_FAILED) {
445 av_log(ctx, AV_LOG_ERROR, "mmap: %s\n", strerror(errno));
446 return AVERROR(errno);
453 static void mmap_release_buffer(AVPacket *pkt)
455 struct v4l2_buffer buf = { 0 };
457 struct buff_data *buf_descriptor = pkt->priv;
459 if (pkt->data == NULL)
462 buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
463 buf.memory = V4L2_MEMORY_MMAP;
464 buf.index = buf_descriptor->index;
465 fd = buf_descriptor->fd;
466 av_free(buf_descriptor);
468 res = v4l2_ioctl(fd, VIDIOC_QBUF, &buf);
470 av_log(NULL, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF): %s\n",
477 #if HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC)
478 static int64_t av_gettime_monotonic(void)
482 clock_gettime(CLOCK_MONOTONIC, &tv);
483 return (int64_t)tv.tv_sec * 1000000 + tv.tv_nsec / 1000;
487 static int init_convert_timestamp(AVFormatContext *ctx, int64_t ts)
489 struct video_data *s = ctx->priv_data;
493 if (s->ts_mode == V4L_TS_ABS &&
494 ts <= now + 1 * AV_TIME_BASE && ts >= now - 10 * AV_TIME_BASE) {
495 av_log(ctx, AV_LOG_INFO, "Detected absolute timestamps\n");
496 s->ts_mode = V4L_TS_CONVERT_READY;
499 #if HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC)
500 now = av_gettime_monotonic();
501 if (s->ts_mode == V4L_TS_MONO2ABS ||
502 (ts <= now + 1 * AV_TIME_BASE && ts >= now - 10 * AV_TIME_BASE)) {
503 int64_t period = av_rescale_q(1, AV_TIME_BASE_Q,
504 ctx->streams[0]->avg_frame_rate);
505 av_log(ctx, AV_LOG_INFO, "Detected monotonic timestamps, converting\n");
506 /* microseconds instead of seconds, MHz instead of Hz */
507 s->timefilter = ff_timefilter_new(1, period, 1.0E-6);
508 s->ts_mode = V4L_TS_CONVERT_READY;
512 av_log(ctx, AV_LOG_ERROR, "Unknown timestamps\n");
516 static int convert_timestamp(AVFormatContext *ctx, int64_t *ts)
518 struct video_data *s = ctx->priv_data;
521 int r = init_convert_timestamp(ctx, *ts);
525 #if HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC)
527 int64_t nowa = av_gettime();
528 int64_t nowm = av_gettime_monotonic();
529 ff_timefilter_update(s->timefilter, nowa, nowm - s->last_time_m);
530 s->last_time_m = nowm;
531 *ts = ff_timefilter_eval(s->timefilter, *ts - nowm);
537 static int mmap_read_frame(AVFormatContext *ctx, AVPacket *pkt)
539 struct video_data *s = ctx->priv_data;
540 struct v4l2_buffer buf = {
541 .type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
542 .memory = V4L2_MEMORY_MMAP
544 struct buff_data *buf_descriptor;
547 /* FIXME: Some special treatment might be needed in case of loss of signal... */
548 while ((res = v4l2_ioctl(s->fd, VIDIOC_DQBUF, &buf)) < 0 && (errno == EINTR));
550 if (errno == EAGAIN) {
552 return AVERROR(EAGAIN);
554 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_DQBUF): %s\n",
557 return AVERROR(errno);
560 if (buf.index >= s->buffers) {
561 av_log(ctx, AV_LOG_ERROR, "Invalid buffer index received.\n");
562 return AVERROR(EINVAL);
565 /* CPIA is a compressed format and we don't know the exact number of bytes
566 * used by a frame, so set it here as the driver announces it.
568 if (ctx->video_codec_id == AV_CODEC_ID_CPIA)
569 s->frame_size = buf.bytesused;
571 if (s->frame_size > 0 && buf.bytesused != s->frame_size) {
572 av_log(ctx, AV_LOG_ERROR,
573 "The v4l2 frame is %d bytes, but %d bytes are expected\n",
574 buf.bytesused, s->frame_size);
576 return AVERROR_INVALIDDATA;
579 /* Image is at s->buff_start[buf.index] */
580 pkt->data= s->buf_start[buf.index];
581 pkt->size = buf.bytesused;
582 pkt->pts = buf.timestamp.tv_sec * INT64_C(1000000) + buf.timestamp.tv_usec;
583 res = convert_timestamp(ctx, &pkt->pts);
586 pkt->destruct = mmap_release_buffer;
587 buf_descriptor = av_malloc(sizeof(struct buff_data));
588 if (buf_descriptor == NULL) {
589 /* Something went wrong... Since av_malloc() failed, we cannot even
590 * allocate a buffer for memcopying into it
592 av_log(ctx, AV_LOG_ERROR, "Failed to allocate a buffer descriptor\n");
593 res = v4l2_ioctl(s->fd, VIDIOC_QBUF, &buf);
595 return AVERROR(ENOMEM);
597 buf_descriptor->fd = s->fd;
598 buf_descriptor->index = buf.index;
599 pkt->priv = buf_descriptor;
601 return s->buf_len[buf.index];
604 static int mmap_start(AVFormatContext *ctx)
606 struct video_data *s = ctx->priv_data;
607 enum v4l2_buf_type type;
610 for (i = 0; i < s->buffers; i++) {
611 struct v4l2_buffer buf = {
612 .type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
614 .memory = V4L2_MEMORY_MMAP
617 res = v4l2_ioctl(s->fd, VIDIOC_QBUF, &buf);
619 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF): %s\n",
622 return AVERROR(errno);
626 type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
627 res = v4l2_ioctl(s->fd, VIDIOC_STREAMON, &type);
629 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_STREAMON): %s\n",
632 return AVERROR(errno);
638 static void mmap_close(struct video_data *s)
640 enum v4l2_buf_type type;
643 type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
644 /* We do not check for the result, because we could
645 * not do anything about it anyway...
647 v4l2_ioctl(s->fd, VIDIOC_STREAMOFF, &type);
648 for (i = 0; i < s->buffers; i++) {
649 v4l2_munmap(s->buf_start[i], s->buf_len[i]);
651 av_free(s->buf_start);
655 static int v4l2_set_parameters(AVFormatContext *s1)
657 struct video_data *s = s1->priv_data;
658 struct v4l2_input input = { 0 };
659 struct v4l2_standard standard = { 0 };
660 struct v4l2_streamparm streamparm = { 0 };
661 struct v4l2_fract *tpf = &streamparm.parm.capture.timeperframe;
662 AVRational framerate_q = { 0 };
665 streamparm.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
668 (ret = av_parse_video_rate(&framerate_q, s->framerate)) < 0) {
669 av_log(s1, AV_LOG_ERROR, "Could not parse framerate '%s'.\n",
674 /* set tv video input */
675 input.index = s->channel;
676 if (v4l2_ioctl(s->fd, VIDIOC_ENUMINPUT, &input) < 0) {
677 av_log(s1, AV_LOG_ERROR, "The V4L2 driver ioctl enum input failed:\n");
681 av_log(s1, AV_LOG_DEBUG, "The V4L2 driver set input_id: %d, input: %s\n",
682 s->channel, input.name);
683 if (v4l2_ioctl(s->fd, VIDIOC_S_INPUT, &input.index) < 0) {
684 av_log(s1, AV_LOG_ERROR,
685 "The V4L2 driver ioctl set input(%d) failed\n",
691 av_log(s1, AV_LOG_DEBUG, "The V4L2 driver set standard: %s\n",
693 /* set tv standard */
696 ret = v4l2_ioctl(s->fd, VIDIOC_ENUMSTD, &standard);
697 if (ret < 0 || !av_strcasecmp(standard.name, s->standard))
701 av_log(s1, AV_LOG_ERROR, "Unknown standard '%s'\n", s->standard);
705 av_log(s1, AV_LOG_DEBUG,
706 "The V4L2 driver set standard: %s, id: %"PRIu64"\n",
707 s->standard, (uint64_t)standard.id);
708 if (v4l2_ioctl(s->fd, VIDIOC_S_STD, &standard.id) < 0) {
709 av_log(s1, AV_LOG_ERROR,
710 "The V4L2 driver ioctl set standard(%s) failed\n",
716 if (framerate_q.num && framerate_q.den) {
717 av_log(s1, AV_LOG_DEBUG, "Setting time per frame to %d/%d\n",
718 framerate_q.den, framerate_q.num);
719 tpf->numerator = framerate_q.den;
720 tpf->denominator = framerate_q.num;
722 if (v4l2_ioctl(s->fd, VIDIOC_S_PARM, &streamparm) != 0) {
723 av_log(s1, AV_LOG_ERROR,
724 "ioctl set time per frame(%d/%d) failed\n",
725 framerate_q.den, framerate_q.num);
729 if (framerate_q.num != tpf->denominator ||
730 framerate_q.den != tpf->numerator) {
731 av_log(s1, AV_LOG_INFO,
732 "The driver changed the time per frame from "
734 framerate_q.den, framerate_q.num,
735 tpf->numerator, tpf->denominator);
738 if (v4l2_ioctl(s->fd, VIDIOC_G_PARM, &streamparm) != 0) {
739 av_log(s1, AV_LOG_ERROR, "ioctl(VIDIOC_G_PARM): %s\n",
741 return AVERROR(errno);
744 s1->streams[0]->avg_frame_rate.num = tpf->denominator;
745 s1->streams[0]->avg_frame_rate.den = tpf->numerator;
750 static uint32_t device_try_init(AVFormatContext *s1,
751 enum AVPixelFormat pix_fmt,
754 enum AVCodecID *codec_id)
756 uint32_t desired_format = fmt_ff2v4l(pix_fmt, s1->video_codec_id);
758 if (desired_format == 0 ||
759 device_init(s1, width, height, desired_format) < 0) {
763 for (i = 0; i<FF_ARRAY_ELEMS(fmt_conversion_table); i++) {
764 if (s1->video_codec_id == AV_CODEC_ID_NONE ||
765 fmt_conversion_table[i].codec_id == s1->video_codec_id) {
766 av_log(s1, AV_LOG_DEBUG, "Trying to set codec:%s pix_fmt:%s\n",
767 avcodec_get_name(fmt_conversion_table[i].codec_id),
768 (char *)av_x_if_null(av_get_pix_fmt_name(fmt_conversion_table[i].ff_fmt), "none"));
770 desired_format = fmt_conversion_table[i].v4l2_fmt;
771 if (device_init(s1, width, height, desired_format) >= 0) {
779 if (desired_format != 0) {
780 *codec_id = fmt_v4l2codec(desired_format);
781 av_assert0(*codec_id != AV_CODEC_ID_NONE);
784 return desired_format;
787 static int v4l2_read_header(AVFormatContext *s1)
789 struct video_data *s = s1->priv_data;
792 uint32_t desired_format;
793 enum AVCodecID codec_id = AV_CODEC_ID_NONE;
794 enum AVPixelFormat pix_fmt = AV_PIX_FMT_NONE;
796 st = avformat_new_stream(s1, NULL);
798 return AVERROR(ENOMEM);
800 s->fd = device_open(s1);
804 if (s->list_format) {
805 list_formats(s1, s->fd, s->list_format);
809 avpriv_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
811 if (s->pixel_format) {
812 AVCodec *codec = avcodec_find_decoder_by_name(s->pixel_format);
815 s1->video_codec_id = codec->id;
817 pix_fmt = av_get_pix_fmt(s->pixel_format);
819 if (pix_fmt == AV_PIX_FMT_NONE && !codec) {
820 av_log(s1, AV_LOG_ERROR, "No such input format: %s.\n",
823 return AVERROR(EINVAL);
827 if (!s->width && !s->height) {
828 struct v4l2_format fmt;
830 av_log(s1, AV_LOG_VERBOSE,
831 "Querying the device for the current frame size\n");
832 fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
833 if (v4l2_ioctl(s->fd, VIDIOC_G_FMT, &fmt) < 0) {
834 av_log(s1, AV_LOG_ERROR, "ioctl(VIDIOC_G_FMT): %s\n",
836 return AVERROR(errno);
839 s->width = fmt.fmt.pix.width;
840 s->height = fmt.fmt.pix.height;
841 av_log(s1, AV_LOG_VERBOSE,
842 "Setting frame size to %dx%d\n", s->width, s->height);
845 desired_format = device_try_init(s1, pix_fmt, &s->width, &s->height,
848 /* If no pixel_format was specified, the codec_id was not known up
849 * until now. Set video_codec_id in the context, as codec_id will
850 * not be available outside this function
852 if (codec_id != AV_CODEC_ID_NONE && s1->video_codec_id == AV_CODEC_ID_NONE)
853 s1->video_codec_id = codec_id;
855 if (desired_format == 0) {
856 av_log(s1, AV_LOG_ERROR, "Cannot find a proper format for "
857 "codec '%s' (id %d), pixel format '%s' (id %d)\n",
858 avcodec_get_name(s1->video_codec_id), s1->video_codec_id,
859 (char *)av_x_if_null(av_get_pix_fmt_name(pix_fmt), "none"), pix_fmt);
864 if ((res = av_image_check_size(s->width, s->height, 0, s1)) < 0)
867 s->frame_format = desired_format;
869 if ((res = v4l2_set_parameters(s1)) < 0)
872 st->codec->pix_fmt = fmt_v4l2ff(desired_format, codec_id);
874 avpicture_get_size(st->codec->pix_fmt, s->width, s->height);
876 if ((res = mmap_init(s1)) ||
877 (res = mmap_start(s1)) < 0) {
882 s->top_field_first = first_field(s->fd);
884 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
885 st->codec->codec_id = codec_id;
886 if (codec_id == AV_CODEC_ID_RAWVIDEO)
887 st->codec->codec_tag =
888 avcodec_pix_fmt_to_codec_tag(st->codec->pix_fmt);
889 if (desired_format == V4L2_PIX_FMT_YVU420)
890 st->codec->codec_tag = MKTAG('Y', 'V', '1', '2');
891 st->codec->width = s->width;
892 st->codec->height = s->height;
893 st->codec->bit_rate = s->frame_size * av_q2d(st->avg_frame_rate) * 8;
898 static int v4l2_read_packet(AVFormatContext *s1, AVPacket *pkt)
900 struct video_data *s = s1->priv_data;
901 AVFrame *frame = s1->streams[0]->codec->coded_frame;
905 if ((res = mmap_read_frame(s1, pkt)) < 0) {
909 if (frame && s->interlaced) {
910 frame->interlaced_frame = 1;
911 frame->top_field_first = s->top_field_first;
917 static int v4l2_read_close(AVFormatContext *s1)
919 struct video_data *s = s1->priv_data;
927 #define OFFSET(x) offsetof(struct video_data, x)
928 #define DEC AV_OPT_FLAG_DECODING_PARAM
930 static const AVOption options[] = {
931 { "standard", "set TV standard, used only by analog frame grabber", OFFSET(standard), AV_OPT_TYPE_STRING, {.str = NULL }, 0, 0, DEC },
932 { "channel", "set TV channel, used only by frame grabber", OFFSET(channel), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, DEC },
933 { "video_size", "set frame size", OFFSET(width), AV_OPT_TYPE_IMAGE_SIZE, {.str = NULL}, 0, 0, DEC },
934 { "pixel_format", "set preferred pixel format", OFFSET(pixel_format), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
935 { "input_format", "set preferred pixel format (for raw video) or codec name", OFFSET(pixel_format), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
936 { "framerate", "set frame rate", OFFSET(framerate), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
938 { "list_formats", "list available formats and exit", OFFSET(list_format), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, DEC, "list_formats" },
939 { "all", "show all available formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.i64 = V4L_ALLFORMATS }, 0, INT_MAX, DEC, "list_formats" },
940 { "raw", "show only non-compressed formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.i64 = V4L_RAWFORMATS }, 0, INT_MAX, DEC, "list_formats" },
941 { "compressed", "show only compressed formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.i64 = V4L_COMPFORMATS }, 0, INT_MAX, DEC, "list_formats" },
943 { "timestamps", "set type of timestamps for grabbed frames", OFFSET(ts_mode), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 2, DEC, "timestamps" },
944 { "ts", "set type of timestamps for grabbed frames", OFFSET(ts_mode), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 2, DEC, "timestamps" },
945 { "default", "use timestamps from the kernel", OFFSET(ts_mode), AV_OPT_TYPE_CONST, {.i64 = V4L_TS_DEFAULT }, 0, 2, DEC, "timestamps" },
946 { "abs", "use absolute timestamps (wall clock)", OFFSET(ts_mode), AV_OPT_TYPE_CONST, {.i64 = V4L_TS_ABS }, 0, 2, DEC, "timestamps" },
947 { "mono2abs", "force conversion from monotonic to absolute timestamps", OFFSET(ts_mode), AV_OPT_TYPE_CONST, {.i64 = V4L_TS_MONO2ABS }, 0, 2, DEC, "timestamps" },
952 static const AVClass v4l2_class = {
953 .class_name = "V4L2 indev",
954 .item_name = av_default_item_name,
956 .version = LIBAVUTIL_VERSION_INT,
959 AVInputFormat ff_v4l2_demuxer = {
960 .name = "video4linux2,v4l2",
961 .long_name = NULL_IF_CONFIG_SMALL("Video4Linux2 device grab"),
962 .priv_data_size = sizeof(struct video_data),
963 .read_header = v4l2_read_header,
964 .read_packet = v4l2_read_packet,
965 .read_close = v4l2_read_close,
966 .flags = AVFMT_NOFILE,
967 .priv_class = &v4l2_class,