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://v4l2spec.bytesex.org/v4l2spec/capture.c)
29 * Thanks to Michael Niedermayer for providing the mapping between
30 * V4L2_PIX_FMT_* and 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>
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 *video_size; /**< String describing video size,
117 set by a private option. */
118 char *pixel_format; /**< Set by a private option. */
119 int list_format; /**< Set by a private option. */
120 char *framerate; /**< Set by a private option. */
129 enum PixelFormat ff_fmt;
130 enum CodecID codec_id;
134 static struct fmt_map fmt_conversion_table[] = {
135 //ff_fmt codec_id v4l2_fmt
136 { PIX_FMT_YUV420P, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_YUV420 },
137 { PIX_FMT_YUV420P, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_YVU420 },
138 { PIX_FMT_YUV422P, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_YUV422P },
139 { PIX_FMT_YUYV422, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_YUYV },
140 { PIX_FMT_UYVY422, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_UYVY },
141 { PIX_FMT_YUV411P, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_YUV411P },
142 { PIX_FMT_YUV410P, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_YUV410 },
143 { PIX_FMT_RGB555LE,CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_RGB555 },
144 { PIX_FMT_RGB555BE,CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_RGB555X },
145 { PIX_FMT_RGB565LE,CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_RGB565 },
146 { PIX_FMT_RGB565BE,CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_RGB565X },
147 { PIX_FMT_BGR24, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_BGR24 },
148 { PIX_FMT_RGB24, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_RGB24 },
149 { PIX_FMT_BGR0, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_BGR32 },
150 { PIX_FMT_0RGB, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_RGB32 },
151 { PIX_FMT_GRAY8, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_GREY },
152 { PIX_FMT_NV12, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_NV12 },
153 { PIX_FMT_NONE, CODEC_ID_MJPEG, V4L2_PIX_FMT_MJPEG },
154 { PIX_FMT_NONE, CODEC_ID_MJPEG, V4L2_PIX_FMT_JPEG },
157 static int device_open(AVFormatContext *ctx)
159 struct v4l2_capability cap;
167 if (ctx->flags & AVFMT_FLAG_NONBLOCK) {
171 fd = v4l2_open(ctx->filename, flags, 0);
175 av_log(ctx, AV_LOG_ERROR, "Cannot open video device %s : %s\n",
176 ctx->filename, strerror(err));
181 fd_libv4l = v4l2_fd_open(fd, 0);
183 err = AVERROR(errno);
184 av_log(ctx, AV_LOG_ERROR, "Cannot open video device with libv4l neither %s : %s\n",
185 ctx->filename, strerror(errno));
191 res = v4l2_ioctl(fd, VIDIOC_QUERYCAP, &cap);
194 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYCAP): %s\n",
200 av_log(ctx, AV_LOG_VERBOSE, "[%d]Capabilities: %x\n",
201 fd, cap.capabilities);
203 if (!(cap.capabilities & V4L2_CAP_VIDEO_CAPTURE)) {
204 av_log(ctx, AV_LOG_ERROR, "Not a video capture device.\n");
210 if (!(cap.capabilities & V4L2_CAP_STREAMING)) {
211 av_log(ctx, AV_LOG_ERROR,
212 "The device does not support the streaming I/O method.\n");
225 static int device_init(AVFormatContext *ctx, int *width, int *height,
228 struct video_data *s = ctx->priv_data;
230 struct v4l2_format fmt = { .type = V4L2_BUF_TYPE_VIDEO_CAPTURE };
231 struct v4l2_pix_format *pix = &fmt.fmt.pix;
236 pix->height = *height;
237 pix->pixelformat = pix_fmt;
238 pix->field = V4L2_FIELD_ANY;
240 res = v4l2_ioctl(fd, VIDIOC_S_FMT, &fmt);
242 if ((*width != fmt.fmt.pix.width) || (*height != fmt.fmt.pix.height)) {
243 av_log(ctx, AV_LOG_INFO,
244 "The V4L2 driver changed the video from %dx%d to %dx%d\n",
245 *width, *height, fmt.fmt.pix.width, fmt.fmt.pix.height);
246 *width = fmt.fmt.pix.width;
247 *height = fmt.fmt.pix.height;
250 if (pix_fmt != fmt.fmt.pix.pixelformat) {
251 av_log(ctx, AV_LOG_DEBUG,
252 "The V4L2 driver changed the pixel format "
253 "from 0x%08X to 0x%08X\n",
254 pix_fmt, fmt.fmt.pix.pixelformat);
258 if (fmt.fmt.pix.field == V4L2_FIELD_INTERLACED) {
259 av_log(ctx, AV_LOG_DEBUG, "The V4L2 driver using the interlaced mode");
266 static int first_field(int fd)
271 res = v4l2_ioctl(fd, VIDIOC_G_STD, &std);
275 if (std & V4L2_STD_NTSC) {
282 static uint32_t fmt_ff2v4l(enum PixelFormat pix_fmt, enum CodecID codec_id)
286 for (i = 0; i < FF_ARRAY_ELEMS(fmt_conversion_table); i++) {
287 if ((codec_id == CODEC_ID_NONE ||
288 fmt_conversion_table[i].codec_id == codec_id) &&
289 (pix_fmt == PIX_FMT_NONE ||
290 fmt_conversion_table[i].ff_fmt == pix_fmt)) {
291 return fmt_conversion_table[i].v4l2_fmt;
298 static enum PixelFormat fmt_v4l2ff(uint32_t v4l2_fmt, enum CodecID codec_id)
302 for (i = 0; i < FF_ARRAY_ELEMS(fmt_conversion_table); i++) {
303 if (fmt_conversion_table[i].v4l2_fmt == v4l2_fmt &&
304 fmt_conversion_table[i].codec_id == codec_id) {
305 return fmt_conversion_table[i].ff_fmt;
312 static enum CodecID fmt_v4l2codec(uint32_t v4l2_fmt)
316 for (i = 0; i < FF_ARRAY_ELEMS(fmt_conversion_table); i++) {
317 if (fmt_conversion_table[i].v4l2_fmt == v4l2_fmt) {
318 return fmt_conversion_table[i].codec_id;
322 return CODEC_ID_NONE;
325 #if HAVE_STRUCT_V4L2_FRMIVALENUM_DISCRETE
326 static void list_framesizes(AVFormatContext *ctx, int fd, uint32_t pixelformat)
328 struct v4l2_frmsizeenum vfse = { .pixel_format = pixelformat };
330 while(!ioctl(fd, VIDIOC_ENUM_FRAMESIZES, &vfse)) {
332 case V4L2_FRMSIZE_TYPE_DISCRETE:
333 av_log(ctx, AV_LOG_INFO, " %ux%u",
334 vfse.discrete.width, vfse.discrete.height);
336 case V4L2_FRMSIZE_TYPE_CONTINUOUS:
337 case V4L2_FRMSIZE_TYPE_STEPWISE:
338 av_log(ctx, AV_LOG_INFO, " {%u-%u, %u}x{%u-%u, %u}",
339 vfse.stepwise.min_width,
340 vfse.stepwise.max_width,
341 vfse.stepwise.step_width,
342 vfse.stepwise.min_height,
343 vfse.stepwise.max_height,
344 vfse.stepwise.step_height);
351 static void list_formats(AVFormatContext *ctx, int fd, int type)
353 struct v4l2_fmtdesc vfd = { .type = V4L2_BUF_TYPE_VIDEO_CAPTURE };
355 while(!ioctl(fd, VIDIOC_ENUM_FMT, &vfd)) {
356 enum CodecID codec_id = fmt_v4l2codec(vfd.pixelformat);
357 enum PixelFormat pix_fmt = fmt_v4l2ff(vfd.pixelformat, codec_id);
361 if (!(vfd.flags & V4L2_FMT_FLAG_COMPRESSED) &&
362 type & V4L_RAWFORMATS) {
363 const char *fmt_name = av_get_pix_fmt_name(pix_fmt);
364 av_log(ctx, AV_LOG_INFO, "R : %9s : %20s :",
365 fmt_name ? fmt_name : "Unsupported",
367 } else if (vfd.flags & V4L2_FMT_FLAG_COMPRESSED &&
368 type & V4L_COMPFORMATS) {
369 AVCodec *codec = avcodec_find_encoder(codec_id);
370 av_log(ctx, AV_LOG_INFO, "C : %9s : %20s :",
371 codec ? codec->name : "Unsupported",
377 #ifdef V4L2_FMT_FLAG_EMULATED
378 if (vfd.flags & V4L2_FMT_FLAG_EMULATED) {
379 av_log(ctx, AV_LOG_WARNING, "%s", "Emulated");
383 #if HAVE_STRUCT_V4L2_FRMIVALENUM_DISCRETE
384 list_framesizes(ctx, fd, vfd.pixelformat);
386 av_log(ctx, AV_LOG_INFO, "\n");
390 static int mmap_init(AVFormatContext *ctx)
393 struct video_data *s = ctx->priv_data;
394 struct v4l2_requestbuffers req = {
395 .type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
396 .count = desired_video_buffers,
397 .memory = V4L2_MEMORY_MMAP
400 res = v4l2_ioctl(s->fd, VIDIOC_REQBUFS, &req);
402 if (errno == EINVAL) {
403 av_log(ctx, AV_LOG_ERROR, "Device does not support mmap\n");
405 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_REQBUFS)\n");
407 return AVERROR(errno);
411 av_log(ctx, AV_LOG_ERROR, "Insufficient buffer memory\n");
412 return AVERROR(ENOMEM);
414 s->buffers = req.count;
415 s->buf_start = av_malloc(sizeof(void *) * s->buffers);
416 if (s->buf_start == NULL) {
417 av_log(ctx, AV_LOG_ERROR, "Cannot allocate buffer pointers\n");
418 return AVERROR(ENOMEM);
420 s->buf_len = av_malloc(sizeof(unsigned int) * s->buffers);
421 if (s->buf_len == NULL) {
422 av_log(ctx, AV_LOG_ERROR, "Cannot allocate buffer sizes\n");
423 av_free(s->buf_start);
424 return AVERROR(ENOMEM);
427 for (i = 0; i < req.count; i++) {
428 struct v4l2_buffer buf = {
429 .type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
431 .memory = V4L2_MEMORY_MMAP
433 res = v4l2_ioctl(s->fd, VIDIOC_QUERYBUF, &buf);
435 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYBUF)\n");
436 return AVERROR(errno);
439 s->buf_len[i] = buf.length;
440 if (s->frame_size > 0 && s->buf_len[i] < s->frame_size) {
441 av_log(ctx, AV_LOG_ERROR,
442 "Buffer len [%d] = %d != %d\n",
443 i, s->buf_len[i], s->frame_size);
447 s->buf_start[i] = v4l2_mmap(NULL, buf.length,
448 PROT_READ | PROT_WRITE, MAP_SHARED,
449 s->fd, buf.m.offset);
451 if (s->buf_start[i] == MAP_FAILED) {
452 av_log(ctx, AV_LOG_ERROR, "mmap: %s\n", strerror(errno));
453 return AVERROR(errno);
460 static void mmap_release_buffer(AVPacket *pkt)
462 struct v4l2_buffer buf = { 0 };
464 struct buff_data *buf_descriptor = pkt->priv;
466 if (pkt->data == NULL)
469 buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
470 buf.memory = V4L2_MEMORY_MMAP;
471 buf.index = buf_descriptor->index;
472 fd = buf_descriptor->fd;
473 av_free(buf_descriptor);
475 res = v4l2_ioctl(fd, VIDIOC_QBUF, &buf);
477 av_log(NULL, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF): %s\n",
484 #if HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC)
485 static int64_t av_gettime_monotonic(void)
489 clock_gettime(CLOCK_MONOTONIC, &tv);
490 return (int64_t)tv.tv_sec * 1000000 + tv.tv_nsec / 1000;
494 static int init_convert_timestamp(AVFormatContext *ctx, int64_t ts)
496 struct video_data *s = ctx->priv_data;
500 if (s->ts_mode == V4L_TS_ABS &&
501 ts <= now + 1 * AV_TIME_BASE && ts >= now - 10 * AV_TIME_BASE) {
502 av_log(ctx, AV_LOG_INFO, "Detected absolute timestamps\n");
503 s->ts_mode = V4L_TS_CONVERT_READY;
506 #if HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC)
507 now = av_gettime_monotonic();
508 if (s->ts_mode == V4L_TS_MONO2ABS ||
509 (ts <= now + 1 * AV_TIME_BASE && ts >= now - 10 * AV_TIME_BASE)) {
510 int64_t period = av_rescale_q(1, ctx->streams[0]->codec->time_base,
512 av_log(ctx, AV_LOG_INFO, "Detected monotonic timestamps, converting\n");
513 /* microseconds instead of seconds, MHz instead of Hz */
514 s->timefilter = ff_timefilter_new(1, period, 1.0E-6);
515 s->ts_mode = V4L_TS_CONVERT_READY;
519 av_log(ctx, AV_LOG_ERROR, "Unknown timestamps\n");
523 static int convert_timestamp(AVFormatContext *ctx, int64_t *ts)
525 struct video_data *s = ctx->priv_data;
528 int r = init_convert_timestamp(ctx, *ts);
532 #if HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC)
534 int64_t nowa = av_gettime();
535 int64_t nowm = av_gettime_monotonic();
536 ff_timefilter_update(s->timefilter, nowa, nowm - s->last_time_m);
537 s->last_time_m = nowm;
538 *ts = ff_timefilter_eval(s->timefilter, *ts - nowm);
544 static int mmap_read_frame(AVFormatContext *ctx, AVPacket *pkt)
546 struct video_data *s = ctx->priv_data;
547 struct v4l2_buffer buf = {
548 .type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
549 .memory = V4L2_MEMORY_MMAP
551 struct buff_data *buf_descriptor;
554 /* FIXME: Some special treatment might be needed in case of loss of signal... */
555 while ((res = v4l2_ioctl(s->fd, VIDIOC_DQBUF, &buf)) < 0 && (errno == EINTR));
557 if (errno == EAGAIN) {
559 return AVERROR(EAGAIN);
561 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_DQBUF): %s\n",
564 return AVERROR(errno);
566 assert(buf.index < s->buffers);
567 if (s->frame_size > 0 && buf.bytesused != s->frame_size) {
568 av_log(ctx, AV_LOG_ERROR,
569 "The v4l2 frame is %d bytes, but %d bytes are expected\n",
570 buf.bytesused, s->frame_size);
572 return AVERROR_INVALIDDATA;
575 /* Image is at s->buff_start[buf.index] */
576 pkt->data= s->buf_start[buf.index];
577 pkt->size = buf.bytesused;
578 pkt->pts = buf.timestamp.tv_sec * INT64_C(1000000) + buf.timestamp.tv_usec;
579 res = convert_timestamp(ctx, &pkt->pts);
582 pkt->destruct = mmap_release_buffer;
583 buf_descriptor = av_malloc(sizeof(struct buff_data));
584 if (buf_descriptor == NULL) {
585 /* Something went wrong... Since av_malloc() failed, we cannot even
586 * allocate a buffer for memcopying into it
588 av_log(ctx, AV_LOG_ERROR, "Failed to allocate a buffer descriptor\n");
589 res = v4l2_ioctl(s->fd, VIDIOC_QBUF, &buf);
591 return AVERROR(ENOMEM);
593 buf_descriptor->fd = s->fd;
594 buf_descriptor->index = buf.index;
595 pkt->priv = buf_descriptor;
597 return s->buf_len[buf.index];
600 static int mmap_start(AVFormatContext *ctx)
602 struct video_data *s = ctx->priv_data;
603 enum v4l2_buf_type type;
606 for (i = 0; i < s->buffers; i++) {
607 struct v4l2_buffer buf = {
608 .type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
610 .memory = V4L2_MEMORY_MMAP
613 res = v4l2_ioctl(s->fd, VIDIOC_QBUF, &buf);
615 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF): %s\n",
618 return AVERROR(errno);
622 type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
623 res = v4l2_ioctl(s->fd, VIDIOC_STREAMON, &type);
625 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_STREAMON): %s\n",
628 return AVERROR(errno);
634 static void mmap_close(struct video_data *s)
636 enum v4l2_buf_type type;
639 type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
640 /* We do not check for the result, because we could
641 * not do anything about it anyway...
643 v4l2_ioctl(s->fd, VIDIOC_STREAMOFF, &type);
644 for (i = 0; i < s->buffers; i++) {
645 v4l2_munmap(s->buf_start[i], s->buf_len[i]);
647 av_free(s->buf_start);
651 static int v4l2_set_parameters(AVFormatContext *s1)
653 struct video_data *s = s1->priv_data;
654 struct v4l2_input input = { 0 };
655 struct v4l2_standard standard = { 0 };
656 struct v4l2_streamparm streamparm = { 0 };
657 struct v4l2_fract *tpf = &streamparm.parm.capture.timeperframe;
658 AVRational framerate_q = { 0 };
661 streamparm.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
664 (ret = av_parse_video_rate(&framerate_q, s->framerate)) < 0) {
665 av_log(s1, AV_LOG_ERROR, "Could not parse framerate '%s'.\n",
670 /* set tv video input */
671 input.index = s->channel;
672 if (v4l2_ioctl(s->fd, VIDIOC_ENUMINPUT, &input) < 0) {
673 av_log(s1, AV_LOG_ERROR, "The V4L2 driver ioctl enum input failed:\n");
677 av_log(s1, AV_LOG_DEBUG, "The V4L2 driver set input_id: %d, input: %s\n",
678 s->channel, input.name);
679 if (v4l2_ioctl(s->fd, VIDIOC_S_INPUT, &input.index) < 0) {
680 av_log(s1, AV_LOG_ERROR,
681 "The V4L2 driver ioctl set input(%d) failed\n",
687 av_log(s1, AV_LOG_DEBUG, "The V4L2 driver set standard: %s\n",
689 /* set tv standard */
692 ret = v4l2_ioctl(s->fd, VIDIOC_ENUMSTD, &standard);
693 if (ret < 0 || !av_strcasecmp(standard.name, s->standard))
697 av_log(s1, AV_LOG_ERROR, "Unknown standard '%s'\n", s->standard);
701 av_log(s1, AV_LOG_DEBUG,
702 "The V4L2 driver set standard: %s, id: %"PRIu64"\n",
703 s->standard, (uint64_t)standard.id);
704 if (v4l2_ioctl(s->fd, VIDIOC_S_STD, &standard.id) < 0) {
705 av_log(s1, AV_LOG_ERROR,
706 "The V4L2 driver ioctl set standard(%s) failed\n",
712 if (framerate_q.num && framerate_q.den) {
713 av_log(s1, AV_LOG_DEBUG, "Setting time per frame to %d/%d\n",
714 framerate_q.den, framerate_q.num);
715 tpf->numerator = framerate_q.den;
716 tpf->denominator = framerate_q.num;
718 if (v4l2_ioctl(s->fd, VIDIOC_S_PARM, &streamparm) != 0) {
719 av_log(s1, AV_LOG_ERROR,
720 "ioctl set time per frame(%d/%d) failed\n",
721 framerate_q.den, framerate_q.num);
725 if (framerate_q.num != tpf->denominator ||
726 framerate_q.den != tpf->numerator) {
727 av_log(s1, AV_LOG_INFO,
728 "The driver changed the time per frame from "
730 framerate_q.den, framerate_q.num,
731 tpf->numerator, tpf->denominator);
734 if (v4l2_ioctl(s->fd, VIDIOC_G_PARM, &streamparm) != 0) {
735 av_log(s1, AV_LOG_ERROR, "ioctl(VIDIOC_G_PARM): %s\n",
737 return AVERROR(errno);
740 s1->streams[0]->codec->time_base.den = tpf->denominator;
741 s1->streams[0]->codec->time_base.num = tpf->numerator;
746 static uint32_t device_try_init(AVFormatContext *s1,
747 enum PixelFormat pix_fmt,
750 enum CodecID *codec_id)
752 uint32_t desired_format = fmt_ff2v4l(pix_fmt, s1->video_codec_id);
754 if (desired_format == 0 ||
755 device_init(s1, width, height, desired_format) < 0) {
759 for (i = 0; i<FF_ARRAY_ELEMS(fmt_conversion_table); i++) {
760 if (s1->video_codec_id == CODEC_ID_NONE ||
761 fmt_conversion_table[i].codec_id == s1->video_codec_id) {
762 desired_format = fmt_conversion_table[i].v4l2_fmt;
763 if (device_init(s1, width, height, desired_format) >= 0) {
771 if (desired_format != 0) {
772 *codec_id = fmt_v4l2codec(desired_format);
773 assert(*codec_id != CODEC_ID_NONE);
776 return desired_format;
779 static int v4l2_read_header(AVFormatContext *s1)
781 struct video_data *s = s1->priv_data;
784 uint32_t desired_format;
785 enum CodecID codec_id;
786 enum PixelFormat pix_fmt = PIX_FMT_NONE;
788 st = avformat_new_stream(s1, NULL);
790 res = AVERROR(ENOMEM);
794 s->fd = device_open(s1);
800 if (s->list_format) {
801 list_formats(s1, s->fd, s->list_format);
806 avpriv_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
809 (res = av_parse_video_size(&s->width, &s->height, s->video_size)) < 0) {
810 av_log(s1, AV_LOG_ERROR, "Could not parse video size '%s'.\n",
815 if (s->pixel_format) {
816 AVCodec *codec = avcodec_find_decoder_by_name(s->pixel_format);
819 s1->video_codec_id = codec->id;
821 pix_fmt = av_get_pix_fmt(s->pixel_format);
823 if (pix_fmt == PIX_FMT_NONE && !codec) {
824 av_log(s1, AV_LOG_ERROR, "No such input format: %s.\n",
827 res = AVERROR(EINVAL);
832 if (!s->width && !s->height) {
833 struct v4l2_format fmt;
835 av_log(s1, AV_LOG_VERBOSE,
836 "Querying the device for the current frame size\n");
837 fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
838 if (v4l2_ioctl(s->fd, VIDIOC_G_FMT, &fmt) < 0) {
839 av_log(s1, AV_LOG_ERROR, "ioctl(VIDIOC_G_FMT): %s\n",
841 res = AVERROR(errno);
845 s->width = fmt.fmt.pix.width;
846 s->height = fmt.fmt.pix.height;
847 av_log(s1, AV_LOG_VERBOSE,
848 "Setting frame size to %dx%d\n", s->width, s->height);
851 desired_format = device_try_init(s1, pix_fmt, &s->width, &s->height,
853 if (desired_format == 0) {
854 av_log(s1, AV_LOG_ERROR, "Cannot find a proper format for "
855 "codec_id %d, pix_fmt %d.\n", s1->video_codec_id, pix_fmt);
861 if ((res = av_image_check_size(s->width, s->height, 0, s1)) < 0)
864 s->frame_format = desired_format;
866 if ((res = v4l2_set_parameters(s1)) < 0)
869 st->codec->pix_fmt = fmt_v4l2ff(desired_format, codec_id);
871 avpicture_get_size(st->codec->pix_fmt, s->width, s->height);
873 if ((res = mmap_init(s1)) ||
874 (res = mmap_start(s1)) < 0) {
879 s->top_field_first = first_field(s->fd);
881 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
882 st->codec->codec_id = codec_id;
883 if (codec_id == CODEC_ID_RAWVIDEO)
884 st->codec->codec_tag =
885 avcodec_pix_fmt_to_codec_tag(st->codec->pix_fmt);
886 if (desired_format == V4L2_PIX_FMT_YVU420)
887 st->codec->codec_tag = MKTAG('Y', 'V', '1', '2');
888 st->codec->width = s->width;
889 st->codec->height = s->height;
890 st->codec->bit_rate = s->frame_size * 1/av_q2d(st->codec->time_base) * 8;
896 static int v4l2_read_packet(AVFormatContext *s1, AVPacket *pkt)
898 struct video_data *s = s1->priv_data;
899 AVFrame *frame = s1->streams[0]->codec->coded_frame;
903 if ((res = mmap_read_frame(s1, pkt)) < 0) {
907 if (frame && s->interlaced) {
908 frame->interlaced_frame = 1;
909 frame->top_field_first = s->top_field_first;
915 static int v4l2_read_close(AVFormatContext *s1)
917 struct video_data *s = s1->priv_data;
925 #define OFFSET(x) offsetof(struct video_data, x)
926 #define DEC AV_OPT_FLAG_DECODING_PARAM
928 static const AVOption options[] = {
929 { "standard", "TV standard, used only by analog frame grabber", OFFSET(standard), AV_OPT_TYPE_STRING, {.str = NULL }, 0, 0, DEC },
930 { "channel", "TV channel, used only by frame grabber", OFFSET(channel), AV_OPT_TYPE_INT, {.dbl = 0 }, 0, INT_MAX, DEC },
931 { "video_size", "A string describing frame size, such as 640x480 or hd720.", OFFSET(video_size), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
932 { "pixel_format", "Preferred pixel format", OFFSET(pixel_format), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
933 { "input_format", "Preferred pixel format (for raw video) or codec name", OFFSET(pixel_format), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
934 { "framerate", "", OFFSET(framerate), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
935 { "list_formats", "List available formats and exit", OFFSET(list_format), AV_OPT_TYPE_INT, {.dbl = 0 }, 0, INT_MAX, DEC, "list_formats" },
936 { "all", "Show all available formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.dbl = V4L_ALLFORMATS }, 0, INT_MAX, DEC, "list_formats" },
937 { "raw", "Show only non-compressed formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.dbl = V4L_RAWFORMATS }, 0, INT_MAX, DEC, "list_formats" },
938 { "compressed", "Show only compressed formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.dbl = V4L_COMPFORMATS }, 0, INT_MAX, DEC, "list_formats" },
939 { "timestamps", "Kind of timestamps for grabbed frames", OFFSET(ts_mode), AV_OPT_TYPE_INT, {.dbl = 0 }, 0, 2, DEC, "timestamps" },
940 { "default", "Use timestamps from the kernel", OFFSET(ts_mode), AV_OPT_TYPE_CONST, {.dbl = V4L_TS_DEFAULT }, 0, 2, DEC, "timestamps" },
941 { "abs", "Use absolute timestamps (wall clock)", OFFSET(ts_mode), AV_OPT_TYPE_CONST, {.dbl = V4L_TS_ABS }, 0, 2, DEC, "timestamps" },
942 { "mono2abs", "Force conversion from monotonic to absolute timestamps", OFFSET(ts_mode), AV_OPT_TYPE_CONST, {.dbl = V4L_TS_MONO2ABS }, 0, 2, DEC, "timestamps" },
943 { "ts", "Kind of timestamps for grabbed frames", OFFSET(ts_mode), AV_OPT_TYPE_INT, {.dbl = 0 }, 0, 2, DEC, "timestamps" },
947 static const AVClass v4l2_class = {
948 .class_name = "V4L2 indev",
949 .item_name = av_default_item_name,
951 .version = LIBAVUTIL_VERSION_INT,
954 AVInputFormat ff_v4l2_demuxer = {
955 .name = "video4linux2,v4l2",
956 .long_name = NULL_IF_CONFIG_SMALL("Video4Linux2 device grab"),
957 .priv_data_size = sizeof(struct video_data),
958 .read_header = v4l2_read_header,
959 .read_packet = v4l2_read_packet,
960 .read_close = v4l2_read_close,
961 .flags = AVFMT_NOFILE,
962 .priv_class = &v4l2_class,