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;
117 char *pixel_format; /**< Set by a private option. */
118 int list_format; /**< Set by a private option. */
119 int list_standard; /**< Set by a private option. */
120 char *framerate; /**< Set by a private option. */
129 enum AVPixelFormat ff_fmt;
130 enum AVCodecID codec_id;
134 static struct fmt_map fmt_conversion_table[] = {
135 //ff_fmt codec_id v4l2_fmt
136 { AV_PIX_FMT_YUV420P, AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_YUV420 },
137 { AV_PIX_FMT_YUV420P, AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_YVU420 },
138 { AV_PIX_FMT_YUV422P, AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_YUV422P },
139 { AV_PIX_FMT_YUYV422, AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_YUYV },
140 { AV_PIX_FMT_UYVY422, AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_UYVY },
141 { AV_PIX_FMT_YUV411P, AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_YUV411P },
142 { AV_PIX_FMT_YUV410P, AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_YUV410 },
143 { AV_PIX_FMT_YUV410P, AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_YVU410 },
144 { AV_PIX_FMT_RGB555LE,AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_RGB555 },
145 { AV_PIX_FMT_RGB555BE,AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_RGB555X },
146 { AV_PIX_FMT_RGB565LE,AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_RGB565 },
147 { AV_PIX_FMT_RGB565BE,AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_RGB565X },
148 { AV_PIX_FMT_BGR24, AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_BGR24 },
149 { AV_PIX_FMT_RGB24, AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_RGB24 },
150 { AV_PIX_FMT_BGR0, AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_BGR32 },
151 { AV_PIX_FMT_0RGB, AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_RGB32 },
152 { AV_PIX_FMT_GRAY8, AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_GREY },
153 #ifdef V4L2_PIX_FMT_Y16
154 { AV_PIX_FMT_GRAY16LE,AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_Y16 },
156 { AV_PIX_FMT_NV12, AV_CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_NV12 },
157 { AV_PIX_FMT_NONE, AV_CODEC_ID_MJPEG, V4L2_PIX_FMT_MJPEG },
158 { AV_PIX_FMT_NONE, AV_CODEC_ID_MJPEG, V4L2_PIX_FMT_JPEG },
159 #ifdef V4L2_PIX_FMT_H264
160 { AV_PIX_FMT_NONE, AV_CODEC_ID_H264, V4L2_PIX_FMT_H264 },
162 #ifdef V4L2_PIX_FMT_CPIA1
163 { AV_PIX_FMT_NONE, AV_CODEC_ID_CPIA, V4L2_PIX_FMT_CPIA1 },
167 static int device_open(AVFormatContext *ctx)
169 struct v4l2_capability cap;
174 if (ctx->flags & AVFMT_FLAG_NONBLOCK) {
178 fd = v4l2_open(ctx->filename, flags, 0);
180 ret = AVERROR(errno);
181 av_log(ctx, AV_LOG_ERROR, "Cannot open video device %s: %s\n",
182 ctx->filename, av_err2str(ret));
186 if (v4l2_ioctl(fd, VIDIOC_QUERYCAP, &cap) < 0) {
187 ret = AVERROR(errno);
188 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYCAP): %s\n",
193 av_log(ctx, AV_LOG_VERBOSE, "fd:%d capabilities:%x\n",
194 fd, cap.capabilities);
196 if (!(cap.capabilities & V4L2_CAP_VIDEO_CAPTURE)) {
197 av_log(ctx, AV_LOG_ERROR, "Not a video capture device.\n");
198 ret = AVERROR(ENODEV);
202 if (!(cap.capabilities & V4L2_CAP_STREAMING)) {
203 av_log(ctx, AV_LOG_ERROR,
204 "The device does not support the streaming I/O method.\n");
205 ret = AVERROR(ENOSYS);
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_decoder(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 void list_standards(AVFormatContext *ctx)
386 struct video_data *s = ctx->priv_data;
387 struct v4l2_standard standard;
392 for (standard.index = 0; ; standard.index++) {
393 if (v4l2_ioctl(s->fd, VIDIOC_ENUMSTD, &standard) < 0) {
394 ret = AVERROR(errno);
395 if (ret == AVERROR(EINVAL)) {
398 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_ENUMSTD): %s\n", av_err2str(ret));
402 av_log(ctx, AV_LOG_INFO, "%2d, %16llx, %s\n",
403 standard.index, standard.id, standard.name);
407 static int mmap_init(AVFormatContext *ctx)
410 struct video_data *s = ctx->priv_data;
411 struct v4l2_requestbuffers req = {
412 .type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
413 .count = desired_video_buffers,
414 .memory = V4L2_MEMORY_MMAP
417 if (v4l2_ioctl(s->fd, VIDIOC_REQBUFS, &req) < 0) {
418 res = AVERROR(errno);
419 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_REQBUFS): %s\n", av_err2str(res));
424 av_log(ctx, AV_LOG_ERROR, "Insufficient buffer memory\n");
425 return AVERROR(ENOMEM);
427 s->buffers = req.count;
428 s->buf_start = av_malloc(sizeof(void *) * s->buffers);
429 if (s->buf_start == NULL) {
430 av_log(ctx, AV_LOG_ERROR, "Cannot allocate buffer pointers\n");
431 return AVERROR(ENOMEM);
433 s->buf_len = av_malloc(sizeof(unsigned int) * s->buffers);
434 if (s->buf_len == NULL) {
435 av_log(ctx, AV_LOG_ERROR, "Cannot allocate buffer sizes\n");
436 av_free(s->buf_start);
437 return AVERROR(ENOMEM);
440 for (i = 0; i < req.count; i++) {
441 struct v4l2_buffer buf = {
442 .type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
444 .memory = V4L2_MEMORY_MMAP
446 if (v4l2_ioctl(s->fd, VIDIOC_QUERYBUF, &buf) < 0) {
447 res = AVERROR(errno);
448 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYBUF): %s\n", av_err2str(res));
452 s->buf_len[i] = buf.length;
453 if (s->frame_size > 0 && s->buf_len[i] < s->frame_size) {
454 av_log(ctx, AV_LOG_ERROR,
455 "buf_len[%d] = %d < expected frame size %d\n",
456 i, s->buf_len[i], s->frame_size);
457 return AVERROR(ENOMEM);
459 s->buf_start[i] = v4l2_mmap(NULL, buf.length,
460 PROT_READ | PROT_WRITE, MAP_SHARED,
461 s->fd, buf.m.offset);
463 if (s->buf_start[i] == MAP_FAILED) {
464 res = AVERROR(errno);
465 av_log(ctx, AV_LOG_ERROR, "mmap: %s\n", av_err2str(res));
473 static void mmap_release_buffer(AVPacket *pkt)
475 struct v4l2_buffer buf = { 0 };
477 struct buff_data *buf_descriptor = pkt->priv;
479 if (pkt->data == NULL)
482 buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
483 buf.memory = V4L2_MEMORY_MMAP;
484 buf.index = buf_descriptor->index;
485 fd = buf_descriptor->fd;
486 av_free(buf_descriptor);
488 if (v4l2_ioctl(fd, VIDIOC_QBUF, &buf) < 0) {
489 res = AVERROR(errno);
490 av_log(NULL, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF): %s\n", av_err2str(res));
497 #if HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC)
498 static int64_t av_gettime_monotonic(void)
502 clock_gettime(CLOCK_MONOTONIC, &tv);
503 return (int64_t)tv.tv_sec * 1000000 + tv.tv_nsec / 1000;
507 static int init_convert_timestamp(AVFormatContext *ctx, int64_t ts)
509 struct video_data *s = ctx->priv_data;
513 if (s->ts_mode == V4L_TS_ABS &&
514 ts <= now + 1 * AV_TIME_BASE && ts >= now - 10 * AV_TIME_BASE) {
515 av_log(ctx, AV_LOG_INFO, "Detected absolute timestamps\n");
516 s->ts_mode = V4L_TS_CONVERT_READY;
519 #if HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC)
520 now = av_gettime_monotonic();
521 if (s->ts_mode == V4L_TS_MONO2ABS ||
522 (ts <= now + 1 * AV_TIME_BASE && ts >= now - 10 * AV_TIME_BASE)) {
523 int64_t period = av_rescale_q(1, AV_TIME_BASE_Q,
524 ctx->streams[0]->avg_frame_rate);
525 av_log(ctx, AV_LOG_INFO, "Detected monotonic timestamps, converting\n");
526 /* microseconds instead of seconds, MHz instead of Hz */
527 s->timefilter = ff_timefilter_new(1, period, 1.0E-6);
528 s->ts_mode = V4L_TS_CONVERT_READY;
532 av_log(ctx, AV_LOG_ERROR, "Unknown timestamps\n");
536 static int convert_timestamp(AVFormatContext *ctx, int64_t *ts)
538 struct video_data *s = ctx->priv_data;
541 int r = init_convert_timestamp(ctx, *ts);
545 #if HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC)
547 int64_t nowa = av_gettime();
548 int64_t nowm = av_gettime_monotonic();
549 ff_timefilter_update(s->timefilter, nowa, nowm - s->last_time_m);
550 s->last_time_m = nowm;
551 *ts = ff_timefilter_eval(s->timefilter, *ts - nowm);
557 static int mmap_read_frame(AVFormatContext *ctx, AVPacket *pkt)
559 struct video_data *s = ctx->priv_data;
560 struct v4l2_buffer buf = {
561 .type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
562 .memory = V4L2_MEMORY_MMAP
564 struct buff_data *buf_descriptor;
567 /* FIXME: Some special treatment might be needed in case of loss of signal... */
568 while ((res = v4l2_ioctl(s->fd, VIDIOC_DQBUF, &buf)) < 0 && (errno == EINTR));
570 if (errno == EAGAIN) {
572 return AVERROR(EAGAIN);
574 res = AVERROR(errno);
575 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_DQBUF): %s\n", av_err2str(res));
579 if (buf.index >= s->buffers) {
580 av_log(ctx, AV_LOG_ERROR, "Invalid buffer index received.\n");
581 return AVERROR(EINVAL);
584 /* CPIA is a compressed format and we don't know the exact number of bytes
585 * used by a frame, so set it here as the driver announces it.
587 if (ctx->video_codec_id == AV_CODEC_ID_CPIA)
588 s->frame_size = buf.bytesused;
590 if (s->frame_size > 0 && buf.bytesused != s->frame_size) {
591 av_log(ctx, AV_LOG_ERROR,
592 "The v4l2 frame is %d bytes, but %d bytes are expected\n",
593 buf.bytesused, s->frame_size);
594 return AVERROR_INVALIDDATA;
597 /* Image is at s->buff_start[buf.index] */
598 pkt->data= s->buf_start[buf.index];
599 pkt->size = buf.bytesused;
600 pkt->pts = buf.timestamp.tv_sec * INT64_C(1000000) + buf.timestamp.tv_usec;
601 res = convert_timestamp(ctx, &pkt->pts);
604 pkt->destruct = mmap_release_buffer;
605 buf_descriptor = av_malloc(sizeof(struct buff_data));
606 if (buf_descriptor == NULL) {
607 /* Something went wrong... Since av_malloc() failed, we cannot even
608 * allocate a buffer for memcopying into it
610 av_log(ctx, AV_LOG_ERROR, "Failed to allocate a buffer descriptor\n");
611 res = v4l2_ioctl(s->fd, VIDIOC_QBUF, &buf);
612 return AVERROR(ENOMEM);
614 buf_descriptor->fd = s->fd;
615 buf_descriptor->index = buf.index;
616 pkt->priv = buf_descriptor;
618 return s->buf_len[buf.index];
621 static int mmap_start(AVFormatContext *ctx)
623 struct video_data *s = ctx->priv_data;
624 enum v4l2_buf_type type;
627 for (i = 0; i < s->buffers; i++) {
628 struct v4l2_buffer buf = {
629 .type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
631 .memory = V4L2_MEMORY_MMAP
634 if (v4l2_ioctl(s->fd, VIDIOC_QBUF, &buf) < 0) {
635 res = AVERROR(errno);
636 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF): %s\n", av_err2str(res));
641 type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
642 if (v4l2_ioctl(s->fd, VIDIOC_STREAMON, &type) < 0) {
643 res = AVERROR(errno);
644 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_STREAMON): %s\n", av_err2str(res));
651 static void mmap_close(struct video_data *s)
653 enum v4l2_buf_type type;
656 type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
657 /* We do not check for the result, because we could
658 * not do anything about it anyway...
660 v4l2_ioctl(s->fd, VIDIOC_STREAMOFF, &type);
661 for (i = 0; i < s->buffers; i++) {
662 v4l2_munmap(s->buf_start[i], s->buf_len[i]);
664 av_free(s->buf_start);
668 static int v4l2_set_parameters(AVFormatContext *s1)
670 struct video_data *s = s1->priv_data;
671 struct v4l2_standard standard = { 0 };
672 struct v4l2_streamparm streamparm = { 0 };
673 struct v4l2_fract *tpf;
674 AVRational framerate_q = { 0 };
678 (ret = av_parse_video_rate(&framerate_q, s->framerate)) < 0) {
679 av_log(s1, AV_LOG_ERROR, "Could not parse framerate '%s'.\n",
687 av_log(s1, AV_LOG_DEBUG, "Setting standard: %s\n", s->standard);
688 /* set tv standard */
691 if (v4l2_ioctl(s->fd, VIDIOC_ENUMSTD, &standard) < 0) {
692 ret = AVERROR(errno);
695 if (!av_strcasecmp(standard.name, s->standard))
699 av_log(s1, AV_LOG_ERROR, "Unknown or unsupported standard '%s'\n", s->standard);
703 if (v4l2_ioctl(s->fd, VIDIOC_S_STD, &standard.id) < 0) {
704 ret = AVERROR(errno);
705 av_log(s1, AV_LOG_ERROR, "ioctl(VIDIOC_S_STD): %s\n", av_err2str(ret));
709 av_log(s1, AV_LOG_WARNING,
710 "This device does not support any standard\n");
715 if (v4l2_ioctl(s->fd, VIDIOC_G_STD, &s->std_id) == 0) {
716 tpf = &standard.frameperiod;
719 if (v4l2_ioctl(s->fd, VIDIOC_ENUMSTD, &standard) < 0) {
720 ret = AVERROR(errno);
721 av_log(s1, AV_LOG_ERROR, "ioctl(VIDIOC_ENUMSTD): %s\n", av_err2str(ret));
724 if (standard.id == s->std_id) {
725 av_log(s1, AV_LOG_DEBUG,
726 "Current standard: %s, id: %"PRIu64", frameperiod: %d/%d\n",
727 standard.name, (uint64_t)standard.id, tpf->numerator, tpf->denominator);
732 tpf = &streamparm.parm.capture.timeperframe;
735 streamparm.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
736 if (v4l2_ioctl(s->fd, VIDIOC_G_PARM, &streamparm) < 0) {
737 ret = AVERROR(errno);
738 av_log(s1, AV_LOG_ERROR, "ioctl(VIDIOC_G_PARM): %s\n", av_err2str(ret));
742 if (framerate_q.num && framerate_q.den) {
743 if (streamparm.parm.capture.capability & V4L2_CAP_TIMEPERFRAME) {
744 tpf = &streamparm.parm.capture.timeperframe;
746 av_log(s1, AV_LOG_DEBUG, "Setting time per frame to %d/%d\n",
747 framerate_q.den, framerate_q.num);
748 tpf->numerator = framerate_q.den;
749 tpf->denominator = framerate_q.num;
751 if (v4l2_ioctl(s->fd, VIDIOC_S_PARM, &streamparm) < 0) {
752 ret = AVERROR(errno);
753 av_log(s1, AV_LOG_ERROR, "ioctl(VIDIOC_S_PARM): %s\n", av_err2str(ret));
757 if (framerate_q.num != tpf->denominator ||
758 framerate_q.den != tpf->numerator) {
759 av_log(s1, AV_LOG_INFO,
760 "The driver changed the time per frame from "
762 framerate_q.den, framerate_q.num,
763 tpf->numerator, tpf->denominator);
766 av_log(s1, AV_LOG_WARNING,
767 "The driver does not allow to change time per frame\n");
770 s1->streams[0]->avg_frame_rate.num = tpf->denominator;
771 s1->streams[0]->avg_frame_rate.den = tpf->numerator;
776 static int device_try_init(AVFormatContext *s1,
777 enum AVPixelFormat pix_fmt,
780 uint32_t *desired_format,
781 enum AVCodecID *codec_id)
785 *desired_format = fmt_ff2v4l(pix_fmt, s1->video_codec_id);
787 if (*desired_format) {
788 ret = device_init(s1, width, height, *desired_format);
791 if (ret != AVERROR(EINVAL))
796 if (!*desired_format) {
797 for (i = 0; i<FF_ARRAY_ELEMS(fmt_conversion_table); i++) {
798 if (s1->video_codec_id == AV_CODEC_ID_NONE ||
799 fmt_conversion_table[i].codec_id == s1->video_codec_id) {
800 av_log(s1, AV_LOG_DEBUG, "Trying to set codec:%s pix_fmt:%s\n",
801 avcodec_get_name(fmt_conversion_table[i].codec_id),
802 (char *)av_x_if_null(av_get_pix_fmt_name(fmt_conversion_table[i].ff_fmt), "none"));
804 *desired_format = fmt_conversion_table[i].v4l2_fmt;
805 ret = device_init(s1, width, height, *desired_format);
808 else if (ret != AVERROR(EINVAL))
814 if (*desired_format == 0) {
815 av_log(s1, AV_LOG_ERROR, "Cannot find a proper format for "
816 "codec '%s' (id %d), pixel format '%s' (id %d)\n",
817 avcodec_get_name(s1->video_codec_id), s1->video_codec_id,
818 (char *)av_x_if_null(av_get_pix_fmt_name(pix_fmt), "none"), pix_fmt);
819 ret = AVERROR(EINVAL);
823 *codec_id = fmt_v4l2codec(*desired_format);
824 av_assert0(*codec_id != AV_CODEC_ID_NONE);
828 static int v4l2_read_header(AVFormatContext *s1)
830 struct video_data *s = s1->priv_data;
833 uint32_t desired_format;
834 enum AVCodecID codec_id = AV_CODEC_ID_NONE;
835 enum AVPixelFormat pix_fmt = AV_PIX_FMT_NONE;
836 struct v4l2_input input = { 0 };
838 st = avformat_new_stream(s1, NULL);
840 return AVERROR(ENOMEM);
842 s->fd = device_open(s1);
846 /* set tv video input */
847 av_log(s1, AV_LOG_DEBUG, "Selecting input_channel: %d\n", s->channel);
848 if (v4l2_ioctl(s->fd, VIDIOC_S_INPUT, &s->channel) < 0) {
849 res = AVERROR(errno);
850 av_log(s1, AV_LOG_ERROR, "ioctl(VIDIOC_S_INPUT): %s\n", av_err2str(res));
854 input.index = s->channel;
855 if (v4l2_ioctl(s->fd, VIDIOC_ENUMINPUT, &input) < 0) {
856 res = AVERROR(errno);
857 av_log(s1, AV_LOG_ERROR, "ioctl(VIDIOC_ENUMINPUT): %s\n", av_err2str(res));
860 s->std_id = input.std;
861 av_log(s1, AV_LOG_DEBUG, "input_channel: %d, input_name: %s\n",
862 s->channel, input.name);
864 if (s->list_format) {
865 list_formats(s1, s->fd, s->list_format);
869 if (s->list_standard) {
874 avpriv_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
876 if (s->pixel_format) {
877 AVCodec *codec = avcodec_find_decoder_by_name(s->pixel_format);
880 s1->video_codec_id = codec->id;
882 pix_fmt = av_get_pix_fmt(s->pixel_format);
884 if (pix_fmt == AV_PIX_FMT_NONE && !codec) {
885 av_log(s1, AV_LOG_ERROR, "No such input format: %s.\n",
888 return AVERROR(EINVAL);
892 if (!s->width && !s->height) {
893 struct v4l2_format fmt;
895 av_log(s1, AV_LOG_VERBOSE,
896 "Querying the device for the current frame size\n");
897 fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
898 if (v4l2_ioctl(s->fd, VIDIOC_G_FMT, &fmt) < 0) {
899 res = AVERROR(errno);
900 av_log(s1, AV_LOG_ERROR, "ioctl(VIDIOC_G_FMT): %s\n", av_err2str(res));
904 s->width = fmt.fmt.pix.width;
905 s->height = fmt.fmt.pix.height;
906 av_log(s1, AV_LOG_VERBOSE,
907 "Setting frame size to %dx%d\n", s->width, s->height);
910 res = device_try_init(s1, pix_fmt, &s->width, &s->height, &desired_format, &codec_id);
916 /* If no pixel_format was specified, the codec_id was not known up
917 * until now. Set video_codec_id in the context, as codec_id will
918 * not be available outside this function
920 if (codec_id != AV_CODEC_ID_NONE && s1->video_codec_id == AV_CODEC_ID_NONE)
921 s1->video_codec_id = codec_id;
923 if ((res = av_image_check_size(s->width, s->height, 0, s1)) < 0)
926 s->frame_format = desired_format;
928 if ((res = v4l2_set_parameters(s1)) < 0)
931 st->codec->pix_fmt = fmt_v4l2ff(desired_format, codec_id);
933 avpicture_get_size(st->codec->pix_fmt, s->width, s->height);
935 if ((res = mmap_init(s1)) ||
936 (res = mmap_start(s1)) < 0) {
941 s->top_field_first = first_field(s->fd);
943 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
944 st->codec->codec_id = codec_id;
945 if (codec_id == AV_CODEC_ID_RAWVIDEO)
946 st->codec->codec_tag =
947 avcodec_pix_fmt_to_codec_tag(st->codec->pix_fmt);
948 if (desired_format == V4L2_PIX_FMT_YVU420)
949 st->codec->codec_tag = MKTAG('Y', 'V', '1', '2');
950 else if (desired_format == V4L2_PIX_FMT_YVU410)
951 st->codec->codec_tag = MKTAG('Y', 'V', 'U', '9');
952 st->codec->width = s->width;
953 st->codec->height = s->height;
954 st->codec->bit_rate = s->frame_size * av_q2d(st->avg_frame_rate) * 8;
959 static int v4l2_read_packet(AVFormatContext *s1, AVPacket *pkt)
961 struct video_data *s = s1->priv_data;
962 AVFrame *frame = s1->streams[0]->codec->coded_frame;
966 if ((res = mmap_read_frame(s1, pkt)) < 0) {
970 if (frame && s->interlaced) {
971 frame->interlaced_frame = 1;
972 frame->top_field_first = s->top_field_first;
978 static int v4l2_read_close(AVFormatContext *s1)
980 struct video_data *s = s1->priv_data;
988 #define OFFSET(x) offsetof(struct video_data, x)
989 #define DEC AV_OPT_FLAG_DECODING_PARAM
991 static const AVOption options[] = {
992 { "standard", "set TV standard, used only by analog frame grabber", OFFSET(standard), AV_OPT_TYPE_STRING, {.str = NULL }, 0, 0, DEC },
993 { "channel", "set TV channel, used only by frame grabber", OFFSET(channel), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, DEC },
994 { "video_size", "set frame size", OFFSET(width), AV_OPT_TYPE_IMAGE_SIZE, {.str = NULL}, 0, 0, DEC },
995 { "pixel_format", "set preferred pixel format", OFFSET(pixel_format), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
996 { "input_format", "set preferred pixel format (for raw video) or codec name", OFFSET(pixel_format), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
997 { "framerate", "set frame rate", OFFSET(framerate), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
999 { "list_formats", "list available formats and exit", OFFSET(list_format), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, DEC, "list_formats" },
1000 { "all", "show all available formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.i64 = V4L_ALLFORMATS }, 0, INT_MAX, DEC, "list_formats" },
1001 { "raw", "show only non-compressed formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.i64 = V4L_RAWFORMATS }, 0, INT_MAX, DEC, "list_formats" },
1002 { "compressed", "show only compressed formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.i64 = V4L_COMPFORMATS }, 0, INT_MAX, DEC, "list_formats" },
1004 { "list_standards", "list supported standards and exit", OFFSET(list_standard), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 1, DEC, "list_standards" },
1005 { "all", "show all supported standards", OFFSET(list_standard), AV_OPT_TYPE_CONST, {.i64 = 1 }, 0, 0, DEC, "list_standards" },
1007 { "timestamps", "set type of timestamps for grabbed frames", OFFSET(ts_mode), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 2, DEC, "timestamps" },
1008 { "ts", "set type of timestamps for grabbed frames", OFFSET(ts_mode), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 2, DEC, "timestamps" },
1009 { "default", "use timestamps from the kernel", OFFSET(ts_mode), AV_OPT_TYPE_CONST, {.i64 = V4L_TS_DEFAULT }, 0, 2, DEC, "timestamps" },
1010 { "abs", "use absolute timestamps (wall clock)", OFFSET(ts_mode), AV_OPT_TYPE_CONST, {.i64 = V4L_TS_ABS }, 0, 2, DEC, "timestamps" },
1011 { "mono2abs", "force conversion from monotonic to absolute timestamps", OFFSET(ts_mode), AV_OPT_TYPE_CONST, {.i64 = V4L_TS_MONO2ABS }, 0, 2, DEC, "timestamps" },
1016 static const AVClass v4l2_class = {
1017 .class_name = "V4L2 indev",
1018 .item_name = av_default_item_name,
1020 .version = LIBAVUTIL_VERSION_INT,
1023 AVInputFormat ff_v4l2_demuxer = {
1024 .name = "video4linux2,v4l2",
1025 .long_name = NULL_IF_CONFIG_SMALL("Video4Linux2 device grab"),
1026 .priv_data_size = sizeof(struct video_data),
1027 .read_header = v4l2_read_header,
1028 .read_packet = v4l2_read_packet,
1029 .read_close = v4l2_read_close,
1030 .flags = AVFMT_NOFILE,
1031 .priv_class = &v4l2_class,