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 "libavutil/parseutils.h"
55 #include "libavutil/pixdesc.h"
56 #include "libavutil/avstring.h"
61 #define v4l2_open open
62 #define v4l2_close close
64 #define v4l2_ioctl ioctl
65 #define v4l2_read read
66 #define v4l2_mmap mmap
67 #define v4l2_munmap munmap
70 static const int desired_video_buffers = 256;
72 #define V4L_ALLFORMATS 3
73 #define V4L_RAWFORMATS 1
74 #define V4L_COMPFORMATS 2
79 int frame_format; /* V4L2_PIX_FMT_* */
87 unsigned int *buf_len;
90 char *video_size; /**< String describing video size,
91 set by a private option. */
92 char *pixel_format; /**< Set by a private option. */
93 int list_format; /**< Set by a private option. */
94 char *framerate; /**< Set by a private option. */
103 enum PixelFormat ff_fmt;
104 enum CodecID codec_id;
108 static struct fmt_map fmt_conversion_table[] = {
109 //ff_fmt codec_id v4l2_fmt
110 { PIX_FMT_YUV420P, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_YUV420 },
111 { PIX_FMT_YUV422P, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_YUV422P },
112 { PIX_FMT_YUYV422, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_YUYV },
113 { PIX_FMT_UYVY422, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_UYVY },
114 { PIX_FMT_YUV411P, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_YUV411P },
115 { PIX_FMT_YUV410P, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_YUV410 },
116 { PIX_FMT_RGB555, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_RGB555 },
117 { PIX_FMT_RGB565, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_RGB565 },
118 { PIX_FMT_BGR24, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_BGR24 },
119 { PIX_FMT_RGB24, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_RGB24 },
120 { PIX_FMT_BGRA, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_BGR32 },
121 { PIX_FMT_GRAY8, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_GREY },
122 { PIX_FMT_NV12, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_NV12 },
123 { PIX_FMT_NONE, CODEC_ID_MJPEG, V4L2_PIX_FMT_MJPEG },
124 { PIX_FMT_NONE, CODEC_ID_MJPEG, V4L2_PIX_FMT_JPEG },
127 static int device_open(AVFormatContext *ctx)
129 struct v4l2_capability cap;
137 if (ctx->flags & AVFMT_FLAG_NONBLOCK) {
141 fd = v4l2_open(ctx->filename, flags, 0);
145 av_log(ctx, AV_LOG_ERROR, "Cannot open video device %s : %s\n",
146 ctx->filename, strerror(err));
151 fd_libv4l = v4l2_fd_open(fd, 0);
153 err = AVERROR(errno);
154 av_log(ctx, AV_LOG_ERROR, "Cannot open video device with libv4l neither %s : %s\n",
155 ctx->filename, strerror(errno));
161 res = v4l2_ioctl(fd, VIDIOC_QUERYCAP, &cap);
164 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYCAP): %s\n",
170 av_log(ctx, AV_LOG_VERBOSE, "[%d]Capabilities: %x\n",
171 fd, cap.capabilities);
173 if (!(cap.capabilities & V4L2_CAP_VIDEO_CAPTURE)) {
174 av_log(ctx, AV_LOG_ERROR, "Not a video capture device.\n");
180 if (!(cap.capabilities & V4L2_CAP_STREAMING)) {
181 av_log(ctx, AV_LOG_ERROR,
182 "The device does not support the streaming I/O method.\n");
195 static int device_init(AVFormatContext *ctx, int *width, int *height,
198 struct video_data *s = ctx->priv_data;
200 struct v4l2_format fmt;
201 struct v4l2_pix_format *pix = &fmt.fmt.pix;
205 memset(&fmt, 0, sizeof(struct v4l2_format));
207 fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
209 pix->height = *height;
210 pix->pixelformat = pix_fmt;
211 pix->field = V4L2_FIELD_ANY;
213 res = v4l2_ioctl(fd, VIDIOC_S_FMT, &fmt);
215 if ((*width != fmt.fmt.pix.width) || (*height != fmt.fmt.pix.height)) {
216 av_log(ctx, AV_LOG_INFO,
217 "The V4L2 driver changed the video from %dx%d to %dx%d\n",
218 *width, *height, fmt.fmt.pix.width, fmt.fmt.pix.height);
219 *width = fmt.fmt.pix.width;
220 *height = fmt.fmt.pix.height;
223 if (pix_fmt != fmt.fmt.pix.pixelformat) {
224 av_log(ctx, AV_LOG_DEBUG,
225 "The V4L2 driver changed the pixel format "
226 "from 0x%08X to 0x%08X\n",
227 pix_fmt, fmt.fmt.pix.pixelformat);
231 if (fmt.fmt.pix.field == V4L2_FIELD_INTERLACED) {
232 av_log(ctx, AV_LOG_DEBUG, "The V4L2 driver using the interlaced mode");
239 static int first_field(int fd)
244 res = v4l2_ioctl(fd, VIDIOC_G_STD, &std);
248 if (std & V4L2_STD_NTSC) {
255 static uint32_t fmt_ff2v4l(enum PixelFormat pix_fmt, enum CodecID codec_id)
259 for (i = 0; i < FF_ARRAY_ELEMS(fmt_conversion_table); i++) {
260 if ((codec_id == CODEC_ID_NONE ||
261 fmt_conversion_table[i].codec_id == codec_id) &&
262 (pix_fmt == PIX_FMT_NONE ||
263 fmt_conversion_table[i].ff_fmt == pix_fmt)) {
264 return fmt_conversion_table[i].v4l2_fmt;
271 static enum PixelFormat fmt_v4l2ff(uint32_t v4l2_fmt, enum CodecID codec_id)
275 for (i = 0; i < FF_ARRAY_ELEMS(fmt_conversion_table); i++) {
276 if (fmt_conversion_table[i].v4l2_fmt == v4l2_fmt &&
277 fmt_conversion_table[i].codec_id == codec_id) {
278 return fmt_conversion_table[i].ff_fmt;
285 static enum CodecID fmt_v4l2codec(uint32_t v4l2_fmt)
289 for (i = 0; i < FF_ARRAY_ELEMS(fmt_conversion_table); i++) {
290 if (fmt_conversion_table[i].v4l2_fmt == v4l2_fmt) {
291 return fmt_conversion_table[i].codec_id;
295 return CODEC_ID_NONE;
298 #if HAVE_STRUCT_V4L2_FRMIVALENUM_DISCRETE
299 static void list_framesizes(AVFormatContext *ctx, int fd, uint32_t pixelformat)
301 struct v4l2_frmsizeenum vfse = { .pixel_format = pixelformat };
303 while(!ioctl(fd, VIDIOC_ENUM_FRAMESIZES, &vfse)) {
305 case V4L2_FRMSIZE_TYPE_DISCRETE:
306 av_log(ctx, AV_LOG_INFO, " %ux%u",
307 vfse.discrete.width, vfse.discrete.height);
309 case V4L2_FRMSIZE_TYPE_CONTINUOUS:
310 case V4L2_FRMSIZE_TYPE_STEPWISE:
311 av_log(ctx, AV_LOG_INFO, " {%u-%u, %u}x{%u-%u, %u}",
312 vfse.stepwise.min_width,
313 vfse.stepwise.max_width,
314 vfse.stepwise.step_width,
315 vfse.stepwise.min_height,
316 vfse.stepwise.max_height,
317 vfse.stepwise.step_height);
324 static void list_formats(AVFormatContext *ctx, int fd, int type)
326 struct v4l2_fmtdesc vfd = { .type = V4L2_BUF_TYPE_VIDEO_CAPTURE };
328 while(!ioctl(fd, VIDIOC_ENUM_FMT, &vfd)) {
329 enum CodecID codec_id = fmt_v4l2codec(vfd.pixelformat);
330 enum PixelFormat pix_fmt = fmt_v4l2ff(vfd.pixelformat, codec_id);
334 if (!(vfd.flags & V4L2_FMT_FLAG_COMPRESSED) &&
335 type & V4L_RAWFORMATS) {
336 const char *fmt_name = av_get_pix_fmt_name(pix_fmt);
337 av_log(ctx, AV_LOG_INFO, "R : %9s : %20s :",
338 fmt_name ? fmt_name : "Unsupported",
340 } else if (vfd.flags & V4L2_FMT_FLAG_COMPRESSED &&
341 type & V4L_COMPFORMATS) {
342 AVCodec *codec = avcodec_find_encoder(codec_id);
343 av_log(ctx, AV_LOG_INFO, "C : %9s : %20s :",
344 codec ? codec->name : "Unsupported",
350 #ifdef V4L2_FMT_FLAG_EMULATED
351 if (vfd.flags & V4L2_FMT_FLAG_EMULATED) {
352 av_log(ctx, AV_LOG_WARNING, "%s", "Emulated");
356 #if HAVE_STRUCT_V4L2_FRMIVALENUM_DISCRETE
357 list_framesizes(ctx, fd, vfd.pixelformat);
359 av_log(ctx, AV_LOG_INFO, "\n");
363 static int mmap_init(AVFormatContext *ctx)
365 struct video_data *s = ctx->priv_data;
366 struct v4l2_requestbuffers req = {0};
369 req.count = desired_video_buffers;
370 req.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
371 req.memory = V4L2_MEMORY_MMAP;
372 res = v4l2_ioctl(s->fd, VIDIOC_REQBUFS, &req);
374 if (errno == EINVAL) {
375 av_log(ctx, AV_LOG_ERROR, "Device does not support mmap\n");
377 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_REQBUFS)\n");
379 return AVERROR(errno);
383 av_log(ctx, AV_LOG_ERROR, "Insufficient buffer memory\n");
384 return AVERROR(ENOMEM);
386 s->buffers = req.count;
387 s->buf_start = av_malloc(sizeof(void *) * s->buffers);
388 if (s->buf_start == NULL) {
389 av_log(ctx, AV_LOG_ERROR, "Cannot allocate buffer pointers\n");
390 return AVERROR(ENOMEM);
392 s->buf_len = av_malloc(sizeof(unsigned int) * s->buffers);
393 if (s->buf_len == NULL) {
394 av_log(ctx, AV_LOG_ERROR, "Cannot allocate buffer sizes\n");
395 av_free(s->buf_start);
396 return AVERROR(ENOMEM);
399 for (i = 0; i < req.count; i++) {
400 struct v4l2_buffer buf = {0};
402 buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
403 buf.memory = V4L2_MEMORY_MMAP;
405 res = v4l2_ioctl(s->fd, VIDIOC_QUERYBUF, &buf);
407 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYBUF)\n");
408 return AVERROR(errno);
411 s->buf_len[i] = buf.length;
412 if (s->frame_size > 0 && s->buf_len[i] < s->frame_size) {
413 av_log(ctx, AV_LOG_ERROR,
414 "Buffer len [%d] = %d != %d\n",
415 i, s->buf_len[i], s->frame_size);
419 s->buf_start[i] = v4l2_mmap(NULL, buf.length,
420 PROT_READ | PROT_WRITE, MAP_SHARED,
421 s->fd, buf.m.offset);
423 if (s->buf_start[i] == MAP_FAILED) {
424 av_log(ctx, AV_LOG_ERROR, "mmap: %s\n", strerror(errno));
425 return AVERROR(errno);
432 static void mmap_release_buffer(AVPacket *pkt)
434 struct v4l2_buffer buf = {0};
436 struct buff_data *buf_descriptor = pkt->priv;
438 if (pkt->data == NULL)
441 buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
442 buf.memory = V4L2_MEMORY_MMAP;
443 buf.index = buf_descriptor->index;
444 fd = buf_descriptor->fd;
445 av_free(buf_descriptor);
447 res = v4l2_ioctl(fd, VIDIOC_QBUF, &buf);
449 av_log(NULL, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF): %s\n",
456 static int mmap_read_frame(AVFormatContext *ctx, AVPacket *pkt)
458 struct video_data *s = ctx->priv_data;
459 struct v4l2_buffer buf = {0};
460 struct buff_data *buf_descriptor;
463 buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
464 buf.memory = V4L2_MEMORY_MMAP;
466 /* FIXME: Some special treatment might be needed in case of loss of signal... */
467 while ((res = v4l2_ioctl(s->fd, VIDIOC_DQBUF, &buf)) < 0 && (errno == EINTR));
469 if (errno == EAGAIN) {
471 return AVERROR(EAGAIN);
473 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_DQBUF): %s\n",
476 return AVERROR(errno);
478 assert(buf.index < s->buffers);
479 if (s->frame_size > 0 && buf.bytesused != s->frame_size) {
480 av_log(ctx, AV_LOG_ERROR,
481 "The v4l2 frame is %d bytes, but %d bytes are expected\n",
482 buf.bytesused, s->frame_size);
484 return AVERROR_INVALIDDATA;
487 /* Image is at s->buff_start[buf.index] */
488 pkt->data= s->buf_start[buf.index];
489 pkt->size = buf.bytesused;
490 pkt->pts = buf.timestamp.tv_sec * INT64_C(1000000) + buf.timestamp.tv_usec;
491 pkt->destruct = mmap_release_buffer;
492 buf_descriptor = av_malloc(sizeof(struct buff_data));
493 if (buf_descriptor == NULL) {
494 /* Something went wrong... Since av_malloc() failed, we cannot even
495 * allocate a buffer for memcopying into it
497 av_log(ctx, AV_LOG_ERROR, "Failed to allocate a buffer descriptor\n");
498 res = v4l2_ioctl(s->fd, VIDIOC_QBUF, &buf);
500 return AVERROR(ENOMEM);
502 buf_descriptor->fd = s->fd;
503 buf_descriptor->index = buf.index;
504 pkt->priv = buf_descriptor;
506 return s->buf_len[buf.index];
509 static int mmap_start(AVFormatContext *ctx)
511 struct video_data *s = ctx->priv_data;
512 enum v4l2_buf_type type;
515 for (i = 0; i < s->buffers; i++) {
516 struct v4l2_buffer buf = {0};
518 buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
519 buf.memory = V4L2_MEMORY_MMAP;
522 res = v4l2_ioctl(s->fd, VIDIOC_QBUF, &buf);
524 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF): %s\n",
527 return AVERROR(errno);
531 type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
532 res = v4l2_ioctl(s->fd, VIDIOC_STREAMON, &type);
534 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_STREAMON): %s\n",
537 return AVERROR(errno);
543 static void mmap_close(struct video_data *s)
545 enum v4l2_buf_type type;
548 type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
549 /* We do not check for the result, because we could
550 * not do anything about it anyway...
552 v4l2_ioctl(s->fd, VIDIOC_STREAMOFF, &type);
553 for (i = 0; i < s->buffers; i++) {
554 v4l2_munmap(s->buf_start[i], s->buf_len[i]);
556 av_free(s->buf_start);
560 static int v4l2_set_parameters(AVFormatContext *s1, AVFormatParameters *ap)
562 struct video_data *s = s1->priv_data;
563 struct v4l2_input input = {0};
564 struct v4l2_standard standard = {0};
565 struct v4l2_streamparm streamparm = {0};
566 struct v4l2_fract *tpf = &streamparm.parm.capture.timeperframe;
568 AVRational framerate_q={0};
570 streamparm.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
573 (ret = av_parse_video_rate(&framerate_q, s->framerate)) < 0) {
574 av_log(s1, AV_LOG_ERROR, "Could not parse framerate '%s'.\n",
579 /* set tv video input */
580 input.index = s->channel;
581 if (v4l2_ioctl(s->fd, VIDIOC_ENUMINPUT, &input) < 0) {
582 av_log(s1, AV_LOG_ERROR, "The V4L2 driver ioctl enum input failed:\n");
586 av_log(s1, AV_LOG_DEBUG, "The V4L2 driver set input_id: %d, input: %s\n",
587 s->channel, input.name);
588 if (v4l2_ioctl(s->fd, VIDIOC_S_INPUT, &input.index) < 0) {
589 av_log(s1, AV_LOG_ERROR,
590 "The V4L2 driver ioctl set input(%d) failed\n",
596 av_log(s1, AV_LOG_DEBUG, "The V4L2 driver set standard: %s\n",
598 /* set tv standard */
601 ret = v4l2_ioctl(s->fd, VIDIOC_ENUMSTD, &standard);
602 if (ret < 0 || !av_strcasecmp(standard.name, s->standard))
606 av_log(s1, AV_LOG_ERROR, "Unknown standard '%s'\n", s->standard);
610 av_log(s1, AV_LOG_DEBUG,
611 "The V4L2 driver set standard: %s, id: %"PRIu64"\n",
612 s->standard, (uint64_t)standard.id);
613 if (v4l2_ioctl(s->fd, VIDIOC_S_STD, &standard.id) < 0) {
614 av_log(s1, AV_LOG_ERROR,
615 "The V4L2 driver ioctl set standard(%s) failed\n",
621 if (framerate_q.num && framerate_q.den) {
622 av_log(s1, AV_LOG_DEBUG, "Setting time per frame to %d/%d\n",
623 framerate_q.den, framerate_q.num);
624 tpf->numerator = framerate_q.den;
625 tpf->denominator = framerate_q.num;
627 if (v4l2_ioctl(s->fd, VIDIOC_S_PARM, &streamparm) != 0) {
628 av_log(s1, AV_LOG_ERROR,
629 "ioctl set time per frame(%d/%d) failed\n",
630 framerate_q.den, framerate_q.num);
634 if (framerate_q.num != tpf->denominator ||
635 framerate_q.den != tpf->numerator) {
636 av_log(s1, AV_LOG_INFO,
637 "The driver changed the time per frame from "
639 framerate_q.den, framerate_q.num,
640 tpf->numerator, tpf->denominator);
643 if (v4l2_ioctl(s->fd, VIDIOC_G_PARM, &streamparm) != 0) {
644 av_log(s1, AV_LOG_ERROR, "ioctl(VIDIOC_G_PARM): %s\n",
646 return AVERROR(errno);
649 s1->streams[0]->codec->time_base.den = tpf->denominator;
650 s1->streams[0]->codec->time_base.num = tpf->numerator;
655 static uint32_t device_try_init(AVFormatContext *s1,
656 enum PixelFormat pix_fmt,
659 enum CodecID *codec_id)
661 uint32_t desired_format = fmt_ff2v4l(pix_fmt, s1->video_codec_id);
663 if (desired_format == 0 ||
664 device_init(s1, width, height, desired_format) < 0) {
668 for (i = 0; i<FF_ARRAY_ELEMS(fmt_conversion_table); i++) {
669 if (s1->video_codec_id == CODEC_ID_NONE ||
670 fmt_conversion_table[i].codec_id == s1->video_codec_id) {
671 desired_format = fmt_conversion_table[i].v4l2_fmt;
672 if (device_init(s1, width, height, desired_format) >= 0) {
680 if (desired_format != 0) {
681 *codec_id = fmt_v4l2codec(desired_format);
682 assert(*codec_id != CODEC_ID_NONE);
685 return desired_format;
688 static int v4l2_read_header(AVFormatContext *s1, AVFormatParameters *ap)
690 struct video_data *s = s1->priv_data;
693 uint32_t desired_format;
694 enum CodecID codec_id;
695 enum PixelFormat pix_fmt = PIX_FMT_NONE;
697 st = avformat_new_stream(s1, NULL);
699 res = AVERROR(ENOMEM);
703 s->fd = device_open(s1);
709 if (s->list_format) {
710 list_formats(s1, s->fd, s->list_format);
715 avpriv_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
718 (res = av_parse_video_size(&s->width, &s->height, s->video_size)) < 0) {
719 av_log(s1, AV_LOG_ERROR, "Could not parse video size '%s'.\n",
724 if (s->pixel_format) {
726 pix_fmt = av_get_pix_fmt(s->pixel_format);
728 if (pix_fmt == PIX_FMT_NONE) {
729 av_log(s1, AV_LOG_ERROR, "No such pixel format: %s.\n",
732 res = AVERROR(EINVAL);
737 if (!s->width && !s->height) {
738 struct v4l2_format fmt;
740 av_log(s1, AV_LOG_VERBOSE,
741 "Querying the device for the current frame size\n");
742 fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
743 if (v4l2_ioctl(s->fd, VIDIOC_G_FMT, &fmt) < 0) {
744 av_log(s1, AV_LOG_ERROR, "ioctl(VIDIOC_G_FMT): %s\n",
746 res = AVERROR(errno);
750 s->width = fmt.fmt.pix.width;
751 s->height = fmt.fmt.pix.height;
752 av_log(s1, AV_LOG_VERBOSE,
753 "Setting frame size to %dx%d\n", s->width, s->height);
756 desired_format = device_try_init(s1, pix_fmt, &s->width, &s->height,
758 if (desired_format == 0) {
759 av_log(s1, AV_LOG_ERROR, "Cannot find a proper format for "
760 "codec_id %d, pix_fmt %d.\n", s1->video_codec_id, pix_fmt);
766 if ((res = av_image_check_size(s->width, s->height, 0, s1)) < 0)
769 s->frame_format = desired_format;
771 if ((res = v4l2_set_parameters(s1, ap)) < 0)
774 st->codec->pix_fmt = fmt_v4l2ff(desired_format, codec_id);
776 avpicture_get_size(st->codec->pix_fmt, s->width, s->height);
778 if ((res = mmap_init(s1)) ||
779 (res = mmap_start(s1)) < 0) {
784 s->top_field_first = first_field(s->fd);
786 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
787 st->codec->codec_id = codec_id;
788 if (codec_id == CODEC_ID_RAWVIDEO)
789 st->codec->codec_tag =
790 avcodec_pix_fmt_to_codec_tag(st->codec->pix_fmt);
791 st->codec->width = s->width;
792 st->codec->height = s->height;
793 st->codec->bit_rate = s->frame_size * 1/av_q2d(st->codec->time_base) * 8;
799 static int v4l2_read_packet(AVFormatContext *s1, AVPacket *pkt)
801 struct video_data *s = s1->priv_data;
802 AVFrame *frame = s1->streams[0]->codec->coded_frame;
806 if ((res = mmap_read_frame(s1, pkt)) < 0) {
810 if (frame && s->interlaced) {
811 frame->interlaced_frame = 1;
812 frame->top_field_first = s->top_field_first;
818 static int v4l2_read_close(AVFormatContext *s1)
820 struct video_data *s = s1->priv_data;
828 #define OFFSET(x) offsetof(struct video_data, x)
829 #define DEC AV_OPT_FLAG_DECODING_PARAM
831 static const AVOption options[] = {
832 { "standard", "TV standard, used only by analog frame grabber", OFFSET(standard), AV_OPT_TYPE_STRING, {.str = NULL }, 0, 0, DEC },
833 { "channel", "TV channel, used only by frame grabber", OFFSET(channel), AV_OPT_TYPE_INT, {.dbl = 0 }, 0, INT_MAX, DEC },
834 { "video_size", "A string describing frame size, such as 640x480 or hd720.", OFFSET(video_size), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
835 { "pixel_format", "", OFFSET(pixel_format), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
836 { "framerate", "", OFFSET(framerate), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
837 { "list_formats", "List available formats and exit", OFFSET(list_format), AV_OPT_TYPE_INT, {.dbl = 0 }, 0, INT_MAX, DEC, "list_formats" },
838 { "all", "Show all available formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.dbl = V4L_ALLFORMATS }, 0, INT_MAX, DEC, "list_formats" },
839 { "raw", "Show only non-compressed formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.dbl = V4L_RAWFORMATS }, 0, INT_MAX, DEC, "list_formats" },
840 { "compressed", "Show only compressed formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.dbl = V4L_COMPFORMATS }, 0, INT_MAX, DEC, "list_formats" },
844 static const AVClass v4l2_class = {
845 .class_name = "V4L2 indev",
846 .item_name = av_default_item_name,
848 .version = LIBAVUTIL_VERSION_INT,
851 AVInputFormat ff_v4l2_demuxer = {
852 .name = "video4linux2,v4l2",
853 .long_name = NULL_IF_CONFIG_SMALL("Video4Linux2 device grab"),
854 .priv_data_size = sizeof(struct video_data),
855 .read_header = v4l2_read_header,
856 .read_packet = v4l2_read_packet,
857 .read_close = v4l2_read_close,
858 .flags = AVFMT_NOFILE,
859 .priv_class = &v4l2_class,