2 * Video4Linux2 grab interface
3 * Copyright (c) 2000,2001 Fabrice Bellard
4 * Copyright (c) 2006 Luca Abeni
6 * Part of this file is based on the V4L2 video capture example
7 * (http://v4l2spec.bytesex.org/v4l2spec/capture.c)
9 * Thanks to Michael Niedermayer for providing the mapping between
10 * V4L2_PIX_FMT_* and PIX_FMT_*
13 * This file is part of FFmpeg.
15 * FFmpeg is free software; you can redistribute it and/or
16 * modify it under the terms of the GNU Lesser General Public
17 * License as published by the Free Software Foundation; either
18 * version 2.1 of the License, or (at your option) any later version.
20 * FFmpeg is distributed in the hope that it will be useful,
21 * but WITHOUT ANY WARRANTY; without even the implied warranty of
22 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
23 * Lesser General Public License for more details.
25 * You should have received a copy of the GNU Lesser General Public
26 * License along with FFmpeg; if not, write to the Free Software
27 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
30 #undef __STRICT_ANSI__ //workaround due to broken kernel headers
32 #include "libavformat/avformat.h"
35 #include <sys/ioctl.h>
38 #if HAVE_SYS_VIDEOIO_H
39 #include <sys/videoio.h>
41 #include <asm/types.h>
42 #include <linux/videodev2.h>
47 static const int desired_video_buffers = 256;
57 int frame_format; /* V4L2_PIX_FMT_* */
58 enum io_method io_method;
65 unsigned int *buf_len;
74 enum PixelFormat ff_fmt;
75 enum CodecID codec_id;
79 static struct fmt_map fmt_conversion_table[] = {
81 .ff_fmt = PIX_FMT_YUV420P,
82 .codec_id = CODEC_ID_RAWVIDEO,
83 .v4l2_fmt = V4L2_PIX_FMT_YUV420,
86 .ff_fmt = PIX_FMT_YUV422P,
87 .codec_id = CODEC_ID_RAWVIDEO,
88 .v4l2_fmt = V4L2_PIX_FMT_YUV422P,
91 .ff_fmt = PIX_FMT_YUYV422,
92 .codec_id = CODEC_ID_RAWVIDEO,
93 .v4l2_fmt = V4L2_PIX_FMT_YUYV,
96 .ff_fmt = PIX_FMT_UYVY422,
97 .codec_id = CODEC_ID_RAWVIDEO,
98 .v4l2_fmt = V4L2_PIX_FMT_UYVY,
101 .ff_fmt = PIX_FMT_YUV411P,
102 .codec_id = CODEC_ID_RAWVIDEO,
103 .v4l2_fmt = V4L2_PIX_FMT_YUV411P,
106 .ff_fmt = PIX_FMT_YUV410P,
107 .codec_id = CODEC_ID_RAWVIDEO,
108 .v4l2_fmt = V4L2_PIX_FMT_YUV410,
111 .ff_fmt = PIX_FMT_RGB555,
112 .codec_id = CODEC_ID_RAWVIDEO,
113 .v4l2_fmt = V4L2_PIX_FMT_RGB555,
116 .ff_fmt = PIX_FMT_RGB565,
117 .codec_id = CODEC_ID_RAWVIDEO,
118 .v4l2_fmt = V4L2_PIX_FMT_RGB565,
121 .ff_fmt = PIX_FMT_BGR24,
122 .codec_id = CODEC_ID_RAWVIDEO,
123 .v4l2_fmt = V4L2_PIX_FMT_BGR24,
126 .ff_fmt = PIX_FMT_RGB24,
127 .codec_id = CODEC_ID_RAWVIDEO,
128 .v4l2_fmt = V4L2_PIX_FMT_RGB24,
131 .ff_fmt = PIX_FMT_BGRA,
132 .codec_id = CODEC_ID_RAWVIDEO,
133 .v4l2_fmt = V4L2_PIX_FMT_BGR32,
136 .ff_fmt = PIX_FMT_GRAY8,
137 .codec_id = CODEC_ID_RAWVIDEO,
138 .v4l2_fmt = V4L2_PIX_FMT_GREY,
141 .ff_fmt = PIX_FMT_NONE,
142 .codec_id = CODEC_ID_MJPEG,
143 .v4l2_fmt = V4L2_PIX_FMT_MJPEG,
146 .ff_fmt = PIX_FMT_NONE,
147 .codec_id = CODEC_ID_MJPEG,
148 .v4l2_fmt = V4L2_PIX_FMT_JPEG,
152 static int device_open(AVFormatContext *ctx, uint32_t *capabilities)
154 struct v4l2_capability cap;
159 if (ctx->flags & AVFMT_FLAG_NONBLOCK) {
162 fd = open(ctx->filename, flags, 0);
164 av_log(ctx, AV_LOG_ERROR, "Cannot open video device %s : %s\n",
165 ctx->filename, strerror(errno));
167 return AVERROR(errno);
170 res = ioctl(fd, VIDIOC_QUERYCAP, &cap);
171 // ENOIOCTLCMD definition only availble on __KERNEL__
172 if (res < 0 && ((err = errno) == 515)) {
173 av_log(ctx, AV_LOG_ERROR, "QUERYCAP not implemented, probably V4L device but not supporting V4L2\n");
179 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYCAP): %s\n",
185 if ((cap.capabilities & V4L2_CAP_VIDEO_CAPTURE) == 0) {
186 av_log(ctx, AV_LOG_ERROR, "Not a video capture device\n");
189 return AVERROR(ENODEV);
191 *capabilities = cap.capabilities;
196 static int device_init(AVFormatContext *ctx, int *width, int *height, uint32_t pix_fmt)
198 struct video_data *s = ctx->priv_data;
200 struct v4l2_format fmt;
203 memset(&fmt, 0, sizeof(struct v4l2_format));
204 fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
205 fmt.fmt.pix.width = *width;
206 fmt.fmt.pix.height = *height;
207 fmt.fmt.pix.pixelformat = pix_fmt;
208 fmt.fmt.pix.field = V4L2_FIELD_INTERLACED;
209 res = ioctl(fd, VIDIOC_S_FMT, &fmt);
210 if ((*width != fmt.fmt.pix.width) || (*height != fmt.fmt.pix.height)) {
211 av_log(ctx, AV_LOG_INFO, "The V4L2 driver changed the video from %dx%d to %dx%d\n", *width, *height, fmt.fmt.pix.width, fmt.fmt.pix.height);
212 *width = fmt.fmt.pix.width;
213 *height = fmt.fmt.pix.height;
216 if (pix_fmt != fmt.fmt.pix.pixelformat) {
217 av_log(ctx, AV_LOG_DEBUG, "The V4L2 driver changed the pixel format from 0x%08X to 0x%08X\n", pix_fmt, fmt.fmt.pix.pixelformat);
224 static int first_field(int fd)
229 res = ioctl(fd, VIDIOC_G_STD, &std);
233 if (std & V4L2_STD_NTSC) {
240 static uint32_t fmt_ff2v4l(enum PixelFormat pix_fmt, enum CodecID codec_id)
244 for (i = 0; i < FF_ARRAY_ELEMS(fmt_conversion_table); i++) {
245 if ((codec_id == CODEC_ID_NONE ||
246 fmt_conversion_table[i].codec_id == codec_id) &&
247 (pix_fmt == PIX_FMT_NONE ||
248 fmt_conversion_table[i].ff_fmt == pix_fmt)) {
249 return fmt_conversion_table[i].v4l2_fmt;
256 static enum PixelFormat fmt_v4l2ff(uint32_t v4l2_fmt, enum CodecID codec_id)
260 for (i = 0; i < FF_ARRAY_ELEMS(fmt_conversion_table); i++) {
261 if (fmt_conversion_table[i].v4l2_fmt == v4l2_fmt &&
262 fmt_conversion_table[i].codec_id == codec_id) {
263 return fmt_conversion_table[i].ff_fmt;
270 static enum CodecID fmt_v4l2codec(uint32_t v4l2_fmt)
274 for (i = 0; i < FF_ARRAY_ELEMS(fmt_conversion_table); i++) {
275 if (fmt_conversion_table[i].v4l2_fmt == v4l2_fmt) {
276 return fmt_conversion_table[i].codec_id;
280 return CODEC_ID_NONE;
283 static int mmap_init(AVFormatContext *ctx)
285 struct video_data *s = ctx->priv_data;
286 struct v4l2_requestbuffers req;
289 memset(&req, 0, sizeof(struct v4l2_requestbuffers));
290 req.count = desired_video_buffers;
291 req.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
292 req.memory = V4L2_MEMORY_MMAP;
293 res = ioctl (s->fd, VIDIOC_REQBUFS, &req);
295 if (errno == EINVAL) {
296 av_log(ctx, AV_LOG_ERROR, "Device does not support mmap\n");
298 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_REQBUFS)\n");
301 return AVERROR(errno);
305 av_log(ctx, AV_LOG_ERROR, "Insufficient buffer memory\n");
307 return AVERROR(ENOMEM);
309 s->buffers = req.count;
310 s->buf_start = av_malloc(sizeof(void *) * s->buffers);
311 if (s->buf_start == NULL) {
312 av_log(ctx, AV_LOG_ERROR, "Cannot allocate buffer pointers\n");
314 return AVERROR(ENOMEM);
316 s->buf_len = av_malloc(sizeof(unsigned int) * s->buffers);
317 if (s->buf_len == NULL) {
318 av_log(ctx, AV_LOG_ERROR, "Cannot allocate buffer sizes\n");
319 av_free(s->buf_start);
321 return AVERROR(ENOMEM);
324 for (i = 0; i < req.count; i++) {
325 struct v4l2_buffer buf;
327 memset(&buf, 0, sizeof(struct v4l2_buffer));
328 buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
329 buf.memory = V4L2_MEMORY_MMAP;
331 res = ioctl (s->fd, VIDIOC_QUERYBUF, &buf);
333 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYBUF)\n");
335 return AVERROR(errno);
338 s->buf_len[i] = buf.length;
339 if (s->frame_size > 0 && s->buf_len[i] < s->frame_size) {
340 av_log(ctx, AV_LOG_ERROR, "Buffer len [%d] = %d != %d\n", i, s->buf_len[i], s->frame_size);
344 s->buf_start[i] = mmap (NULL, buf.length,
345 PROT_READ | PROT_WRITE, MAP_SHARED, s->fd, buf.m.offset);
346 if (s->buf_start[i] == MAP_FAILED) {
347 av_log(ctx, AV_LOG_ERROR, "mmap: %s\n", strerror(errno));
349 return AVERROR(errno);
356 static int read_init(AVFormatContext *ctx)
361 static void mmap_release_buffer(AVPacket *pkt)
363 struct v4l2_buffer buf;
365 struct buff_data *buf_descriptor = pkt->priv;
367 if (pkt->data == NULL) {
371 memset(&buf, 0, sizeof(struct v4l2_buffer));
372 buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
373 buf.memory = V4L2_MEMORY_MMAP;
374 buf.index = buf_descriptor->index;
375 fd = buf_descriptor->fd;
376 av_free(buf_descriptor);
378 res = ioctl (fd, VIDIOC_QBUF, &buf);
380 av_log(NULL, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF)\n");
386 static int mmap_read_frame(AVFormatContext *ctx, AVPacket *pkt)
388 struct video_data *s = ctx->priv_data;
389 struct v4l2_buffer buf;
390 struct buff_data *buf_descriptor;
393 memset(&buf, 0, sizeof(struct v4l2_buffer));
394 buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
395 buf.memory = V4L2_MEMORY_MMAP;
397 /* FIXME: Some special treatment might be needed in case of loss of signal... */
398 while ((res = ioctl(s->fd, VIDIOC_DQBUF, &buf)) < 0 && (errno == EINTR));
400 if (errno == EAGAIN) {
403 return AVERROR(EAGAIN);
405 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_DQBUF): %s\n", strerror(errno));
407 return AVERROR(errno);
409 assert (buf.index < s->buffers);
410 if (s->frame_size > 0 && buf.bytesused != s->frame_size) {
411 av_log(ctx, AV_LOG_ERROR, "The v4l2 frame is %d bytes, but %d bytes are expected\n", buf.bytesused, s->frame_size);
413 return AVERROR_INVALIDDATA;
416 /* Image is at s->buff_start[buf.index] */
417 pkt->data= s->buf_start[buf.index];
418 pkt->size = buf.bytesused;
419 pkt->pts = buf.timestamp.tv_sec * INT64_C(1000000) + buf.timestamp.tv_usec;
420 pkt->destruct = mmap_release_buffer;
421 buf_descriptor = av_malloc(sizeof(struct buff_data));
422 if (buf_descriptor == NULL) {
423 /* Something went wrong... Since av_malloc() failed, we cannot even
424 * allocate a buffer for memcopying into it
426 av_log(ctx, AV_LOG_ERROR, "Failed to allocate a buffer descriptor\n");
427 res = ioctl (s->fd, VIDIOC_QBUF, &buf);
429 return AVERROR(ENOMEM);
431 buf_descriptor->fd = s->fd;
432 buf_descriptor->index = buf.index;
433 pkt->priv = buf_descriptor;
435 return s->buf_len[buf.index];
438 static int read_frame(AVFormatContext *ctx, AVPacket *pkt)
443 static int mmap_start(AVFormatContext *ctx)
445 struct video_data *s = ctx->priv_data;
446 enum v4l2_buf_type type;
449 for (i = 0; i < s->buffers; i++) {
450 struct v4l2_buffer buf;
452 memset(&buf, 0, sizeof(struct v4l2_buffer));
453 buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
454 buf.memory = V4L2_MEMORY_MMAP;
457 res = ioctl (s->fd, VIDIOC_QBUF, &buf);
459 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF): %s\n", strerror(errno));
461 return AVERROR(errno);
465 type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
466 res = ioctl (s->fd, VIDIOC_STREAMON, &type);
468 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_STREAMON): %s\n", strerror(errno));
470 return AVERROR(errno);
476 static void mmap_close(struct video_data *s)
478 enum v4l2_buf_type type;
481 type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
482 /* We do not check for the result, because we could
483 * not do anything about it anyway...
485 ioctl(s->fd, VIDIOC_STREAMOFF, &type);
486 for (i = 0; i < s->buffers; i++) {
487 munmap(s->buf_start[i], s->buf_len[i]);
489 av_free(s->buf_start);
493 static int v4l2_set_parameters( AVFormatContext *s1, AVFormatParameters *ap )
495 struct video_data *s = s1->priv_data;
496 struct v4l2_input input;
497 struct v4l2_standard standard;
501 /* set tv video input */
502 memset (&input, 0, sizeof (input));
503 input.index = ap->channel;
504 if(ioctl (s->fd, VIDIOC_ENUMINPUT, &input) < 0) {
505 av_log(s1, AV_LOG_ERROR, "The V4L2 driver ioctl enum input failed:\n");
509 av_log(s1, AV_LOG_DEBUG, "The V4L2 driver set input_id: %d, input: %s\n",
510 ap->channel, input.name);
511 if(ioctl (s->fd, VIDIOC_S_INPUT, &input.index) < 0 ) {
512 av_log(s1, AV_LOG_ERROR, "The V4L2 driver ioctl set input(%d) failed\n",
519 av_log(s1, AV_LOG_DEBUG, "The V4L2 driver set standard: %s\n",
521 /* set tv standard */
522 memset (&standard, 0, sizeof (standard));
525 if (ioctl(s->fd, VIDIOC_ENUMSTD, &standard) < 0) {
526 av_log(s1, AV_LOG_ERROR, "The V4L2 driver ioctl set standard(%s) failed\n",
531 if(!strcasecmp(standard.name, ap->standard)) {
536 av_log(s1, AV_LOG_DEBUG, "The V4L2 driver set standard: %s, id: %"PRIu64"\n",
537 ap->standard, (uint64_t)standard.id);
538 if (ioctl(s->fd, VIDIOC_S_STD, &standard.id) < 0) {
539 av_log(s1, AV_LOG_ERROR, "The V4L2 driver ioctl set standard(%s) failed\n",
548 static uint32_t device_try_init(AVFormatContext *s1,
549 const AVFormatParameters *ap,
552 enum CodecID *codec_id)
554 uint32_t desired_format = fmt_ff2v4l(ap->pix_fmt, s1->video_codec_id);
556 if (desired_format == 0 ||
557 device_init(s1, width, height, desired_format) < 0) {
561 for (i = 0; i<FF_ARRAY_ELEMS(fmt_conversion_table); i++) {
562 if (s1->video_codec_id == CODEC_ID_NONE ||
563 fmt_conversion_table[i].codec_id == s1->video_codec_id) {
564 desired_format = fmt_conversion_table[i].v4l2_fmt;
565 if (device_init(s1, width, height, desired_format) >= 0) {
572 if (desired_format != 0) {
573 *codec_id = fmt_v4l2codec(desired_format);
574 assert(*codec_id != CODEC_ID_NONE);
577 return desired_format;
580 static int v4l2_read_header(AVFormatContext *s1, AVFormatParameters *ap)
582 struct video_data *s = s1->priv_data;
585 uint32_t desired_format, capabilities;
586 enum CodecID codec_id;
588 st = av_new_stream(s1, 0);
590 return AVERROR(ENOMEM);
592 av_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
594 s->width = ap->width;
595 s->height = ap->height;
598 s->fd = device_open(s1, &capabilities);
602 av_log(s1, AV_LOG_VERBOSE, "[%d]Capabilities: %x\n", s->fd, capabilities);
604 if (!s->width && !s->height) {
605 struct v4l2_format fmt;
607 av_log(s1, AV_LOG_VERBOSE, "Querying the device for the current frame size\n");
608 fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
609 if (ioctl(s->fd, VIDIOC_G_FMT, &fmt) < 0) {
610 av_log(s1, AV_LOG_ERROR, "ioctl(VIDIOC_G_FMT): %s\n", strerror(errno));
611 return AVERROR(errno);
613 s->width = fmt.fmt.pix.width;
614 s->height = fmt.fmt.pix.height;
615 av_log(s1, AV_LOG_VERBOSE, "Setting frame size to %dx%d\n", s->width, s->height);
618 desired_format = device_try_init(s1, ap, &s->width, &s->height, &codec_id);
619 if (desired_format == 0) {
620 av_log(s1, AV_LOG_ERROR, "Cannot find a proper format for "
621 "codec_id %d, pix_fmt %d.\n", s1->video_codec_id, ap->pix_fmt);
626 if (avcodec_check_dimensions(s1, s->width, s->height) < 0)
627 return AVERROR(EINVAL);
628 s->frame_format = desired_format;
630 if( v4l2_set_parameters( s1, ap ) < 0 )
633 st->codec->pix_fmt = fmt_v4l2ff(desired_format, codec_id);
634 s->frame_size = avpicture_get_size(st->codec->pix_fmt, s->width, s->height);
635 if (capabilities & V4L2_CAP_STREAMING) {
636 s->io_method = io_mmap;
639 res = mmap_start(s1);
642 s->io_method = io_read;
650 s->top_field_first = first_field(s->fd);
652 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
653 st->codec->codec_id = codec_id;
654 st->codec->width = s->width;
655 st->codec->height = s->height;
656 st->codec->time_base.den = ap->time_base.den;
657 st->codec->time_base.num = ap->time_base.num;
658 st->codec->bit_rate = s->frame_size * 1/av_q2d(st->codec->time_base) * 8;
663 static int v4l2_read_packet(AVFormatContext *s1, AVPacket *pkt)
665 struct video_data *s = s1->priv_data;
668 if (s->io_method == io_mmap) {
670 res = mmap_read_frame(s1, pkt);
671 } else if (s->io_method == io_read) {
672 if (av_new_packet(pkt, s->frame_size) < 0)
675 res = read_frame(s1, pkt);
683 if (s1->streams[0]->codec->coded_frame) {
684 s1->streams[0]->codec->coded_frame->interlaced_frame = 1;
685 s1->streams[0]->codec->coded_frame->top_field_first = s->top_field_first;
691 static int v4l2_read_close(AVFormatContext *s1)
693 struct video_data *s = s1->priv_data;
695 if (s->io_method == io_mmap) {
703 AVInputFormat v4l2_demuxer = {
705 NULL_IF_CONFIG_SMALL("Video4Linux2 device grab"),
706 sizeof(struct video_data),
711 .flags = AVFMT_NOFILE,