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 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_CPIA1
154 { AV_PIX_FMT_NONE, AV_CODEC_ID_CPIA, V4L2_PIX_FMT_CPIA1 },
158 static int device_open(AVFormatContext *ctx)
160 struct v4l2_capability cap;
165 if (ctx->flags & AVFMT_FLAG_NONBLOCK) {
169 fd = v4l2_open(ctx->filename, flags, 0);
173 av_log(ctx, AV_LOG_ERROR, "Cannot open video device %s : %s\n",
174 ctx->filename, strerror(err));
179 res = v4l2_ioctl(fd, VIDIOC_QUERYCAP, &cap);
182 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYCAP): %s\n",
188 av_log(ctx, AV_LOG_VERBOSE, "[%d]Capabilities: %x\n",
189 fd, cap.capabilities);
191 if (!(cap.capabilities & V4L2_CAP_VIDEO_CAPTURE)) {
192 av_log(ctx, AV_LOG_ERROR, "Not a video capture device.\n");
198 if (!(cap.capabilities & V4L2_CAP_STREAMING)) {
199 av_log(ctx, AV_LOG_ERROR,
200 "The device does not support the streaming I/O method.\n");
213 static int device_init(AVFormatContext *ctx, int *width, int *height,
216 struct video_data *s = ctx->priv_data;
218 struct v4l2_format fmt = { .type = V4L2_BUF_TYPE_VIDEO_CAPTURE };
219 struct v4l2_pix_format *pix = &fmt.fmt.pix;
224 pix->height = *height;
225 pix->pixelformat = pix_fmt;
226 pix->field = V4L2_FIELD_ANY;
228 res = v4l2_ioctl(fd, VIDIOC_S_FMT, &fmt);
230 if ((*width != fmt.fmt.pix.width) || (*height != fmt.fmt.pix.height)) {
231 av_log(ctx, AV_LOG_INFO,
232 "The V4L2 driver changed the video from %dx%d to %dx%d\n",
233 *width, *height, fmt.fmt.pix.width, fmt.fmt.pix.height);
234 *width = fmt.fmt.pix.width;
235 *height = fmt.fmt.pix.height;
238 if (pix_fmt != fmt.fmt.pix.pixelformat) {
239 av_log(ctx, AV_LOG_DEBUG,
240 "The V4L2 driver changed the pixel format "
241 "from 0x%08X to 0x%08X\n",
242 pix_fmt, fmt.fmt.pix.pixelformat);
246 if (fmt.fmt.pix.field == V4L2_FIELD_INTERLACED) {
247 av_log(ctx, AV_LOG_DEBUG, "The V4L2 driver using the interlaced mode");
254 static int first_field(int fd)
259 res = v4l2_ioctl(fd, VIDIOC_G_STD, &std);
263 if (std & V4L2_STD_NTSC) {
270 static uint32_t fmt_ff2v4l(enum AVPixelFormat pix_fmt, enum AVCodecID codec_id)
274 for (i = 0; i < FF_ARRAY_ELEMS(fmt_conversion_table); i++) {
275 if ((codec_id == AV_CODEC_ID_NONE ||
276 fmt_conversion_table[i].codec_id == codec_id) &&
277 (pix_fmt == AV_PIX_FMT_NONE ||
278 fmt_conversion_table[i].ff_fmt == pix_fmt)) {
279 return fmt_conversion_table[i].v4l2_fmt;
286 static enum AVPixelFormat fmt_v4l2ff(uint32_t v4l2_fmt, enum AVCodecID codec_id)
290 for (i = 0; i < FF_ARRAY_ELEMS(fmt_conversion_table); i++) {
291 if (fmt_conversion_table[i].v4l2_fmt == v4l2_fmt &&
292 fmt_conversion_table[i].codec_id == codec_id) {
293 return fmt_conversion_table[i].ff_fmt;
297 return AV_PIX_FMT_NONE;
300 static enum AVCodecID fmt_v4l2codec(uint32_t v4l2_fmt)
304 for (i = 0; i < FF_ARRAY_ELEMS(fmt_conversion_table); i++) {
305 if (fmt_conversion_table[i].v4l2_fmt == v4l2_fmt) {
306 return fmt_conversion_table[i].codec_id;
310 return AV_CODEC_ID_NONE;
313 #if HAVE_STRUCT_V4L2_FRMIVALENUM_DISCRETE
314 static void list_framesizes(AVFormatContext *ctx, int fd, uint32_t pixelformat)
316 struct v4l2_frmsizeenum vfse = { .pixel_format = pixelformat };
318 while(!ioctl(fd, VIDIOC_ENUM_FRAMESIZES, &vfse)) {
320 case V4L2_FRMSIZE_TYPE_DISCRETE:
321 av_log(ctx, AV_LOG_INFO, " %ux%u",
322 vfse.discrete.width, vfse.discrete.height);
324 case V4L2_FRMSIZE_TYPE_CONTINUOUS:
325 case V4L2_FRMSIZE_TYPE_STEPWISE:
326 av_log(ctx, AV_LOG_INFO, " {%u-%u, %u}x{%u-%u, %u}",
327 vfse.stepwise.min_width,
328 vfse.stepwise.max_width,
329 vfse.stepwise.step_width,
330 vfse.stepwise.min_height,
331 vfse.stepwise.max_height,
332 vfse.stepwise.step_height);
339 static void list_formats(AVFormatContext *ctx, int fd, int type)
341 struct v4l2_fmtdesc vfd = { .type = V4L2_BUF_TYPE_VIDEO_CAPTURE };
343 while(!ioctl(fd, VIDIOC_ENUM_FMT, &vfd)) {
344 enum AVCodecID codec_id = fmt_v4l2codec(vfd.pixelformat);
345 enum AVPixelFormat pix_fmt = fmt_v4l2ff(vfd.pixelformat, codec_id);
349 if (!(vfd.flags & V4L2_FMT_FLAG_COMPRESSED) &&
350 type & V4L_RAWFORMATS) {
351 const char *fmt_name = av_get_pix_fmt_name(pix_fmt);
352 av_log(ctx, AV_LOG_INFO, "R : %9s : %20s :",
353 fmt_name ? fmt_name : "Unsupported",
355 } else if (vfd.flags & V4L2_FMT_FLAG_COMPRESSED &&
356 type & V4L_COMPFORMATS) {
357 AVCodec *codec = avcodec_find_encoder(codec_id);
358 av_log(ctx, AV_LOG_INFO, "C : %9s : %20s :",
359 codec ? codec->name : "Unsupported",
365 #ifdef V4L2_FMT_FLAG_EMULATED
366 if (vfd.flags & V4L2_FMT_FLAG_EMULATED) {
367 av_log(ctx, AV_LOG_WARNING, "%s", "Emulated");
371 #if HAVE_STRUCT_V4L2_FRMIVALENUM_DISCRETE
372 list_framesizes(ctx, fd, vfd.pixelformat);
374 av_log(ctx, AV_LOG_INFO, "\n");
378 static int mmap_init(AVFormatContext *ctx)
381 struct video_data *s = ctx->priv_data;
382 struct v4l2_requestbuffers req = {
383 .type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
384 .count = desired_video_buffers,
385 .memory = V4L2_MEMORY_MMAP
388 res = v4l2_ioctl(s->fd, VIDIOC_REQBUFS, &req);
390 if (errno == EINVAL) {
391 av_log(ctx, AV_LOG_ERROR, "Device does not support mmap\n");
393 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_REQBUFS)\n");
395 return AVERROR(errno);
399 av_log(ctx, AV_LOG_ERROR, "Insufficient buffer memory\n");
400 return AVERROR(ENOMEM);
402 s->buffers = req.count;
403 s->buf_start = av_malloc(sizeof(void *) * s->buffers);
404 if (s->buf_start == NULL) {
405 av_log(ctx, AV_LOG_ERROR, "Cannot allocate buffer pointers\n");
406 return AVERROR(ENOMEM);
408 s->buf_len = av_malloc(sizeof(unsigned int) * s->buffers);
409 if (s->buf_len == NULL) {
410 av_log(ctx, AV_LOG_ERROR, "Cannot allocate buffer sizes\n");
411 av_free(s->buf_start);
412 return AVERROR(ENOMEM);
415 for (i = 0; i < req.count; i++) {
416 struct v4l2_buffer buf = {
417 .type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
419 .memory = V4L2_MEMORY_MMAP
421 res = v4l2_ioctl(s->fd, VIDIOC_QUERYBUF, &buf);
423 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYBUF)\n");
424 return AVERROR(errno);
427 s->buf_len[i] = buf.length;
428 if (s->frame_size > 0 && s->buf_len[i] < s->frame_size) {
429 av_log(ctx, AV_LOG_ERROR,
430 "Buffer len [%d] = %d != %d\n",
431 i, s->buf_len[i], s->frame_size);
435 s->buf_start[i] = v4l2_mmap(NULL, buf.length,
436 PROT_READ | PROT_WRITE, MAP_SHARED,
437 s->fd, buf.m.offset);
439 if (s->buf_start[i] == MAP_FAILED) {
440 av_log(ctx, AV_LOG_ERROR, "mmap: %s\n", strerror(errno));
441 return AVERROR(errno);
448 static void mmap_release_buffer(AVPacket *pkt)
450 struct v4l2_buffer buf = { 0 };
452 struct buff_data *buf_descriptor = pkt->priv;
454 if (pkt->data == NULL)
457 buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
458 buf.memory = V4L2_MEMORY_MMAP;
459 buf.index = buf_descriptor->index;
460 fd = buf_descriptor->fd;
461 av_free(buf_descriptor);
463 res = v4l2_ioctl(fd, VIDIOC_QBUF, &buf);
465 av_log(NULL, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF): %s\n",
472 #if HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC)
473 static int64_t av_gettime_monotonic(void)
477 clock_gettime(CLOCK_MONOTONIC, &tv);
478 return (int64_t)tv.tv_sec * 1000000 + tv.tv_nsec / 1000;
482 static int init_convert_timestamp(AVFormatContext *ctx, int64_t ts)
484 struct video_data *s = ctx->priv_data;
488 if (s->ts_mode == V4L_TS_ABS &&
489 ts <= now + 1 * AV_TIME_BASE && ts >= now - 10 * AV_TIME_BASE) {
490 av_log(ctx, AV_LOG_INFO, "Detected absolute timestamps\n");
491 s->ts_mode = V4L_TS_CONVERT_READY;
494 #if HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC)
495 now = av_gettime_monotonic();
496 if (s->ts_mode == V4L_TS_MONO2ABS ||
497 (ts <= now + 1 * AV_TIME_BASE && ts >= now - 10 * AV_TIME_BASE)) {
498 int64_t period = av_rescale_q(1, ctx->streams[0]->codec->time_base,
500 av_log(ctx, AV_LOG_INFO, "Detected monotonic timestamps, converting\n");
501 /* microseconds instead of seconds, MHz instead of Hz */
502 s->timefilter = ff_timefilter_new(1, period, 1.0E-6);
503 s->ts_mode = V4L_TS_CONVERT_READY;
507 av_log(ctx, AV_LOG_ERROR, "Unknown timestamps\n");
511 static int convert_timestamp(AVFormatContext *ctx, int64_t *ts)
513 struct video_data *s = ctx->priv_data;
516 int r = init_convert_timestamp(ctx, *ts);
520 #if HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC)
522 int64_t nowa = av_gettime();
523 int64_t nowm = av_gettime_monotonic();
524 ff_timefilter_update(s->timefilter, nowa, nowm - s->last_time_m);
525 s->last_time_m = nowm;
526 *ts = ff_timefilter_eval(s->timefilter, *ts - nowm);
532 static int mmap_read_frame(AVFormatContext *ctx, AVPacket *pkt)
534 struct video_data *s = ctx->priv_data;
535 struct v4l2_buffer buf = {
536 .type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
537 .memory = V4L2_MEMORY_MMAP
539 struct buff_data *buf_descriptor;
542 /* FIXME: Some special treatment might be needed in case of loss of signal... */
543 while ((res = v4l2_ioctl(s->fd, VIDIOC_DQBUF, &buf)) < 0 && (errno == EINTR));
545 if (errno == EAGAIN) {
547 return AVERROR(EAGAIN);
549 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_DQBUF): %s\n",
552 return AVERROR(errno);
554 av_assert0(buf.index < s->buffers);
556 /* CPIA is a compressed format and we don't know the exact number of bytes
557 * used by a frame, so set it here as the driver announces it.
559 if (ctx->video_codec_id == AV_CODEC_ID_CPIA)
560 s->frame_size = buf.bytesused;
562 if (s->frame_size > 0 && buf.bytesused != s->frame_size) {
563 av_log(ctx, AV_LOG_ERROR,
564 "The v4l2 frame is %d bytes, but %d bytes are expected\n",
565 buf.bytesused, s->frame_size);
567 return AVERROR_INVALIDDATA;
570 /* Image is at s->buff_start[buf.index] */
571 pkt->data= s->buf_start[buf.index];
572 pkt->size = buf.bytesused;
573 pkt->pts = buf.timestamp.tv_sec * INT64_C(1000000) + buf.timestamp.tv_usec;
574 res = convert_timestamp(ctx, &pkt->pts);
577 pkt->destruct = mmap_release_buffer;
578 buf_descriptor = av_malloc(sizeof(struct buff_data));
579 if (buf_descriptor == NULL) {
580 /* Something went wrong... Since av_malloc() failed, we cannot even
581 * allocate a buffer for memcopying into it
583 av_log(ctx, AV_LOG_ERROR, "Failed to allocate a buffer descriptor\n");
584 res = v4l2_ioctl(s->fd, VIDIOC_QBUF, &buf);
586 return AVERROR(ENOMEM);
588 buf_descriptor->fd = s->fd;
589 buf_descriptor->index = buf.index;
590 pkt->priv = buf_descriptor;
592 return s->buf_len[buf.index];
595 static int mmap_start(AVFormatContext *ctx)
597 struct video_data *s = ctx->priv_data;
598 enum v4l2_buf_type type;
601 for (i = 0; i < s->buffers; i++) {
602 struct v4l2_buffer buf = {
603 .type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
605 .memory = V4L2_MEMORY_MMAP
608 res = v4l2_ioctl(s->fd, VIDIOC_QBUF, &buf);
610 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF): %s\n",
613 return AVERROR(errno);
617 type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
618 res = v4l2_ioctl(s->fd, VIDIOC_STREAMON, &type);
620 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_STREAMON): %s\n",
623 return AVERROR(errno);
629 static void mmap_close(struct video_data *s)
631 enum v4l2_buf_type type;
634 type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
635 /* We do not check for the result, because we could
636 * not do anything about it anyway...
638 v4l2_ioctl(s->fd, VIDIOC_STREAMOFF, &type);
639 for (i = 0; i < s->buffers; i++) {
640 v4l2_munmap(s->buf_start[i], s->buf_len[i]);
642 av_free(s->buf_start);
646 static int v4l2_set_parameters(AVFormatContext *s1)
648 struct video_data *s = s1->priv_data;
649 struct v4l2_input input = { 0 };
650 struct v4l2_standard standard = { 0 };
651 struct v4l2_streamparm streamparm = { 0 };
652 struct v4l2_fract *tpf = &streamparm.parm.capture.timeperframe;
653 AVRational framerate_q = { 0 };
656 streamparm.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
659 (ret = av_parse_video_rate(&framerate_q, s->framerate)) < 0) {
660 av_log(s1, AV_LOG_ERROR, "Could not parse framerate '%s'.\n",
665 /* set tv video input */
666 input.index = s->channel;
667 if (v4l2_ioctl(s->fd, VIDIOC_ENUMINPUT, &input) < 0) {
668 av_log(s1, AV_LOG_ERROR, "The V4L2 driver ioctl enum input failed:\n");
672 av_log(s1, AV_LOG_DEBUG, "The V4L2 driver set input_id: %d, input: %s\n",
673 s->channel, input.name);
674 if (v4l2_ioctl(s->fd, VIDIOC_S_INPUT, &input.index) < 0) {
675 av_log(s1, AV_LOG_ERROR,
676 "The V4L2 driver ioctl set input(%d) failed\n",
682 av_log(s1, AV_LOG_DEBUG, "The V4L2 driver set standard: %s\n",
684 /* set tv standard */
687 ret = v4l2_ioctl(s->fd, VIDIOC_ENUMSTD, &standard);
688 if (ret < 0 || !av_strcasecmp(standard.name, s->standard))
692 av_log(s1, AV_LOG_ERROR, "Unknown standard '%s'\n", s->standard);
696 av_log(s1, AV_LOG_DEBUG,
697 "The V4L2 driver set standard: %s, id: %"PRIu64"\n",
698 s->standard, (uint64_t)standard.id);
699 if (v4l2_ioctl(s->fd, VIDIOC_S_STD, &standard.id) < 0) {
700 av_log(s1, AV_LOG_ERROR,
701 "The V4L2 driver ioctl set standard(%s) failed\n",
707 if (framerate_q.num && framerate_q.den) {
708 av_log(s1, AV_LOG_DEBUG, "Setting time per frame to %d/%d\n",
709 framerate_q.den, framerate_q.num);
710 tpf->numerator = framerate_q.den;
711 tpf->denominator = framerate_q.num;
713 if (v4l2_ioctl(s->fd, VIDIOC_S_PARM, &streamparm) != 0) {
714 av_log(s1, AV_LOG_ERROR,
715 "ioctl set time per frame(%d/%d) failed\n",
716 framerate_q.den, framerate_q.num);
720 if (framerate_q.num != tpf->denominator ||
721 framerate_q.den != tpf->numerator) {
722 av_log(s1, AV_LOG_INFO,
723 "The driver changed the time per frame from "
725 framerate_q.den, framerate_q.num,
726 tpf->numerator, tpf->denominator);
729 if (v4l2_ioctl(s->fd, VIDIOC_G_PARM, &streamparm) != 0) {
730 av_log(s1, AV_LOG_ERROR, "ioctl(VIDIOC_G_PARM): %s\n",
732 return AVERROR(errno);
735 s1->streams[0]->codec->time_base.den = tpf->denominator;
736 s1->streams[0]->codec->time_base.num = tpf->numerator;
741 static uint32_t device_try_init(AVFormatContext *s1,
742 enum AVPixelFormat pix_fmt,
745 enum AVCodecID *codec_id)
747 uint32_t desired_format = fmt_ff2v4l(pix_fmt, s1->video_codec_id);
749 if (desired_format == 0 ||
750 device_init(s1, width, height, desired_format) < 0) {
754 for (i = 0; i<FF_ARRAY_ELEMS(fmt_conversion_table); i++) {
755 if (s1->video_codec_id == AV_CODEC_ID_NONE ||
756 fmt_conversion_table[i].codec_id == s1->video_codec_id) {
757 desired_format = fmt_conversion_table[i].v4l2_fmt;
758 if (device_init(s1, width, height, desired_format) >= 0) {
766 if (desired_format != 0) {
767 *codec_id = fmt_v4l2codec(desired_format);
768 av_assert0(*codec_id != AV_CODEC_ID_NONE);
771 return desired_format;
774 static int v4l2_read_header(AVFormatContext *s1)
776 struct video_data *s = s1->priv_data;
779 uint32_t desired_format;
780 enum AVCodecID codec_id = AV_CODEC_ID_NONE;
781 enum AVPixelFormat pix_fmt = AV_PIX_FMT_NONE;
783 st = avformat_new_stream(s1, NULL);
785 res = AVERROR(ENOMEM);
789 s->fd = device_open(s1);
795 if (s->list_format) {
796 list_formats(s1, s->fd, s->list_format);
801 avpriv_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
803 if (s->pixel_format) {
804 AVCodec *codec = avcodec_find_decoder_by_name(s->pixel_format);
807 s1->video_codec_id = codec->id;
809 pix_fmt = av_get_pix_fmt(s->pixel_format);
811 if (pix_fmt == AV_PIX_FMT_NONE && !codec) {
812 av_log(s1, AV_LOG_ERROR, "No such input format: %s.\n",
815 res = AVERROR(EINVAL);
820 if (!s->width && !s->height) {
821 struct v4l2_format fmt;
823 av_log(s1, AV_LOG_VERBOSE,
824 "Querying the device for the current frame size\n");
825 fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
826 if (v4l2_ioctl(s->fd, VIDIOC_G_FMT, &fmt) < 0) {
827 av_log(s1, AV_LOG_ERROR, "ioctl(VIDIOC_G_FMT): %s\n",
829 res = AVERROR(errno);
833 s->width = fmt.fmt.pix.width;
834 s->height = fmt.fmt.pix.height;
835 av_log(s1, AV_LOG_VERBOSE,
836 "Setting frame size to %dx%d\n", s->width, s->height);
839 desired_format = device_try_init(s1, pix_fmt, &s->width, &s->height,
842 /* If no pixel_format was specified, the codec_id was not known up
843 * until now. Set video_codec_id in the context, as codec_id will
844 * not be available outside this function
846 if (codec_id != AV_CODEC_ID_NONE && s1->video_codec_id == AV_CODEC_ID_NONE)
847 s1->video_codec_id = codec_id;
849 if (desired_format == 0) {
850 av_log(s1, AV_LOG_ERROR, "Cannot find a proper format for "
851 "codec_id %d, pix_fmt %d.\n", s1->video_codec_id, pix_fmt);
857 if ((res = av_image_check_size(s->width, s->height, 0, s1)) < 0)
860 s->frame_format = desired_format;
862 if ((res = v4l2_set_parameters(s1)) < 0)
865 st->codec->pix_fmt = fmt_v4l2ff(desired_format, codec_id);
867 avpicture_get_size(st->codec->pix_fmt, s->width, s->height);
869 if ((res = mmap_init(s1)) ||
870 (res = mmap_start(s1)) < 0) {
875 s->top_field_first = first_field(s->fd);
877 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
878 st->codec->codec_id = codec_id;
879 if (codec_id == AV_CODEC_ID_RAWVIDEO)
880 st->codec->codec_tag =
881 avcodec_pix_fmt_to_codec_tag(st->codec->pix_fmt);
882 if (desired_format == V4L2_PIX_FMT_YVU420)
883 st->codec->codec_tag = MKTAG('Y', 'V', '1', '2');
884 st->codec->width = s->width;
885 st->codec->height = s->height;
886 st->codec->bit_rate = s->frame_size * 1/av_q2d(st->codec->time_base) * 8;
892 static int v4l2_read_packet(AVFormatContext *s1, AVPacket *pkt)
894 struct video_data *s = s1->priv_data;
895 AVFrame *frame = s1->streams[0]->codec->coded_frame;
899 if ((res = mmap_read_frame(s1, pkt)) < 0) {
903 if (frame && s->interlaced) {
904 frame->interlaced_frame = 1;
905 frame->top_field_first = s->top_field_first;
911 static int v4l2_read_close(AVFormatContext *s1)
913 struct video_data *s = s1->priv_data;
921 #define OFFSET(x) offsetof(struct video_data, x)
922 #define DEC AV_OPT_FLAG_DECODING_PARAM
924 static const AVOption options[] = {
925 { "standard", "TV standard, used only by analog frame grabber", OFFSET(standard), AV_OPT_TYPE_STRING, {.str = NULL }, 0, 0, DEC },
926 { "channel", "TV channel, used only by frame grabber", OFFSET(channel), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, DEC },
927 { "video_size", "A string describing frame size, such as 640x480 or hd720.", OFFSET(width), AV_OPT_TYPE_IMAGE_SIZE, {.str = NULL}, 0, 0, DEC },
928 { "pixel_format", "Preferred pixel format", OFFSET(pixel_format), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
929 { "input_format", "Preferred pixel format (for raw video) or codec name", OFFSET(pixel_format), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
930 { "framerate", "", OFFSET(framerate), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
931 { "list_formats", "List available formats and exit", OFFSET(list_format), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, DEC, "list_formats" },
932 { "all", "Show all available formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.i64 = V4L_ALLFORMATS }, 0, INT_MAX, DEC, "list_formats" },
933 { "raw", "Show only non-compressed formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.i64 = V4L_RAWFORMATS }, 0, INT_MAX, DEC, "list_formats" },
934 { "compressed", "Show only compressed formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.i64 = V4L_COMPFORMATS }, 0, INT_MAX, DEC, "list_formats" },
935 { "timestamps", "Kind of timestamps for grabbed frames", OFFSET(ts_mode), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 2, DEC, "timestamps" },
936 { "default", "Use timestamps from the kernel", OFFSET(ts_mode), AV_OPT_TYPE_CONST, {.i64 = V4L_TS_DEFAULT }, 0, 2, DEC, "timestamps" },
937 { "abs", "Use absolute timestamps (wall clock)", OFFSET(ts_mode), AV_OPT_TYPE_CONST, {.i64 = V4L_TS_ABS }, 0, 2, DEC, "timestamps" },
938 { "mono2abs", "Force conversion from monotonic to absolute timestamps", OFFSET(ts_mode), AV_OPT_TYPE_CONST, {.i64 = V4L_TS_MONO2ABS }, 0, 2, DEC, "timestamps" },
939 { "ts", "Kind of timestamps for grabbed frames", OFFSET(ts_mode), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 2, DEC, "timestamps" },
943 static const AVClass v4l2_class = {
944 .class_name = "V4L2 indev",
945 .item_name = av_default_item_name,
947 .version = LIBAVUTIL_VERSION_INT,
950 AVInputFormat ff_v4l2_demuxer = {
951 .name = "video4linux2,v4l2",
952 .long_name = NULL_IF_CONFIG_SMALL("Video4Linux2 device grab"),
953 .priv_data_size = sizeof(struct video_data),
954 .read_header = v4l2_read_header,
955 .read_packet = v4l2_read_packet,
956 .read_close = v4l2_read_close,
957 .flags = AVFMT_NOFILE,
958 .priv_class = &v4l2_class,