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 #ifdef 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;
67 unsigned int *buf_len;
76 enum PixelFormat ff_fmt;
80 static struct fmt_map fmt_conversion_table[] = {
82 .ff_fmt = PIX_FMT_YUV420P,
83 .v4l2_fmt = V4L2_PIX_FMT_YUV420,
86 .ff_fmt = PIX_FMT_YUV422P,
87 .v4l2_fmt = V4L2_PIX_FMT_YUV422P,
90 .ff_fmt = PIX_FMT_YUYV422,
91 .v4l2_fmt = V4L2_PIX_FMT_YUYV,
94 .ff_fmt = PIX_FMT_UYVY422,
95 .v4l2_fmt = V4L2_PIX_FMT_UYVY,
98 .ff_fmt = PIX_FMT_YUV411P,
99 .v4l2_fmt = V4L2_PIX_FMT_YUV411P,
102 .ff_fmt = PIX_FMT_YUV410P,
103 .v4l2_fmt = V4L2_PIX_FMT_YUV410,
106 .ff_fmt = PIX_FMT_RGB555,
107 .v4l2_fmt = V4L2_PIX_FMT_RGB555,
110 .ff_fmt = PIX_FMT_RGB565,
111 .v4l2_fmt = V4L2_PIX_FMT_RGB565,
114 .ff_fmt = PIX_FMT_BGR24,
115 .v4l2_fmt = V4L2_PIX_FMT_BGR24,
118 .ff_fmt = PIX_FMT_RGB24,
119 .v4l2_fmt = V4L2_PIX_FMT_RGB24,
122 .ff_fmt = PIX_FMT_BGRA,
123 .v4l2_fmt = V4L2_PIX_FMT_BGR32,
126 .ff_fmt = PIX_FMT_GRAY8,
127 .v4l2_fmt = V4L2_PIX_FMT_GREY,
131 static int device_open(AVFormatContext *ctx, uint32_t *capabilities)
133 struct v4l2_capability cap;
138 if (ctx->flags & AVFMT_FLAG_NONBLOCK) {
141 fd = open(ctx->filename, flags, 0);
143 av_log(ctx, AV_LOG_ERROR, "Cannot open video device %s : %s\n",
144 ctx->filename, strerror(errno));
149 res = ioctl(fd, VIDIOC_QUERYCAP, &cap);
150 // ENOIOCTLCMD definition only availble on __KERNEL__
151 if (res < 0 && errno == 515)
153 av_log(ctx, AV_LOG_ERROR, "QUERYCAP not implemented, probably V4L device but not supporting V4L2\n");
159 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYCAP): %s\n",
165 if ((cap.capabilities & V4L2_CAP_VIDEO_CAPTURE) == 0) {
166 av_log(ctx, AV_LOG_ERROR, "Not a video capture device\n");
171 *capabilities = cap.capabilities;
176 static int device_init(AVFormatContext *ctx, int *width, int *height, int pix_fmt)
178 struct video_data *s = ctx->priv_data;
180 struct v4l2_format fmt;
183 memset(&fmt, 0, sizeof(struct v4l2_format));
184 fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
185 fmt.fmt.pix.width = *width;
186 fmt.fmt.pix.height = *height;
187 fmt.fmt.pix.pixelformat = pix_fmt;
188 fmt.fmt.pix.field = V4L2_FIELD_INTERLACED;
189 res = ioctl(fd, VIDIOC_S_FMT, &fmt);
190 if ((*width != fmt.fmt.pix.width) || (*height != fmt.fmt.pix.height)) {
191 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);
192 *width = fmt.fmt.pix.width;
193 *height = fmt.fmt.pix.height;
196 if (pix_fmt != fmt.fmt.pix.pixelformat) {
197 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);
204 static int first_field(int fd)
209 res = ioctl(fd, VIDIOC_G_STD, &std);
213 if (std & V4L2_STD_NTSC) {
220 static uint32_t fmt_ff2v4l(enum PixelFormat pix_fmt)
224 for (i = 0; i < FF_ARRAY_ELEMS(fmt_conversion_table); i++) {
225 if (fmt_conversion_table[i].ff_fmt == pix_fmt) {
226 return fmt_conversion_table[i].v4l2_fmt;
233 static enum PixelFormat fmt_v4l2ff(uint32_t pix_fmt)
237 for (i = 0; i < FF_ARRAY_ELEMS(fmt_conversion_table); i++) {
238 if (fmt_conversion_table[i].v4l2_fmt == pix_fmt) {
239 return fmt_conversion_table[i].ff_fmt;
246 static int mmap_init(AVFormatContext *ctx)
248 struct video_data *s = ctx->priv_data;
249 struct v4l2_requestbuffers req;
252 memset(&req, 0, sizeof(struct v4l2_requestbuffers));
253 req.count = desired_video_buffers;
254 req.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
255 req.memory = V4L2_MEMORY_MMAP;
256 res = ioctl (s->fd, VIDIOC_REQBUFS, &req);
258 if (errno == EINVAL) {
259 av_log(ctx, AV_LOG_ERROR, "Device does not support mmap\n");
261 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_REQBUFS)\n");
268 av_log(ctx, AV_LOG_ERROR, "Insufficient buffer memory\n");
272 s->buffers = req.count;
273 s->buf_start = av_malloc(sizeof(void *) * s->buffers);
274 if (s->buf_start == NULL) {
275 av_log(ctx, AV_LOG_ERROR, "Cannot allocate buffer pointers\n");
279 s->buf_len = av_malloc(sizeof(unsigned int) * s->buffers);
280 if (s->buf_len == NULL) {
281 av_log(ctx, AV_LOG_ERROR, "Cannot allocate buffer sizes\n");
282 av_free(s->buf_start);
287 for (i = 0; i < req.count; i++) {
288 struct v4l2_buffer buf;
290 memset(&buf, 0, sizeof(struct v4l2_buffer));
291 buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
292 buf.memory = V4L2_MEMORY_MMAP;
294 res = ioctl (s->fd, VIDIOC_QUERYBUF, &buf);
296 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYBUF)\n");
301 s->buf_len[i] = buf.length;
302 if (s->buf_len[i] < s->frame_size) {
303 av_log(ctx, AV_LOG_ERROR, "Buffer len [%d] = %d != %d\n", i, s->buf_len[i], s->frame_size);
307 s->buf_start[i] = mmap (NULL, buf.length,
308 PROT_READ | PROT_WRITE, MAP_SHARED, s->fd, buf.m.offset);
309 if (s->buf_start[i] == MAP_FAILED) {
310 av_log(ctx, AV_LOG_ERROR, "mmap: %s\n", strerror(errno));
319 static int read_init(AVFormatContext *ctx)
324 static void mmap_release_buffer(AVPacket *pkt)
326 struct v4l2_buffer buf;
328 struct buff_data *buf_descriptor = pkt->priv;
330 memset(&buf, 0, sizeof(struct v4l2_buffer));
331 buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
332 buf.memory = V4L2_MEMORY_MMAP;
333 buf.index = buf_descriptor->index;
334 fd = buf_descriptor->fd;
335 av_free(buf_descriptor);
337 res = ioctl (fd, VIDIOC_QBUF, &buf);
339 av_log(NULL, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF)\n");
345 static int mmap_read_frame(AVFormatContext *ctx, AVPacket *pkt)
347 struct video_data *s = ctx->priv_data;
348 struct v4l2_buffer buf;
349 struct buff_data *buf_descriptor;
352 memset(&buf, 0, sizeof(struct v4l2_buffer));
353 buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
354 buf.memory = V4L2_MEMORY_MMAP;
356 /* FIXME: Some special treatment might be needed in case of loss of signal... */
357 while ((res = ioctl(s->fd, VIDIOC_DQBUF, &buf)) < 0 && (errno == EINTR));
359 if (errno == EAGAIN) {
362 return AVERROR(EAGAIN);
364 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_DQBUF): %s\n", strerror(errno));
368 assert (buf.index < s->buffers);
369 if (buf.bytesused != s->frame_size) {
370 av_log(ctx, AV_LOG_ERROR, "The v4l2 frame is %d bytes, but %d bytes are expected\n", buf.bytesused, s->frame_size);
375 /* Image is at s->buff_start[buf.index] */
376 pkt->data= s->buf_start[buf.index];
377 pkt->size = buf.bytesused;
378 pkt->pts = buf.timestamp.tv_sec * INT64_C(1000000) + buf.timestamp.tv_usec;
379 pkt->destruct = mmap_release_buffer;
380 buf_descriptor = av_malloc(sizeof(struct buff_data));
381 if (buf_descriptor == NULL) {
382 /* Something went wrong... Since av_malloc() failed, we cannot even
383 * allocate a buffer for memcopying into it
385 av_log(ctx, AV_LOG_ERROR, "Failed to allocate a buffer descriptor\n");
386 res = ioctl (s->fd, VIDIOC_QBUF, &buf);
390 buf_descriptor->fd = s->fd;
391 buf_descriptor->index = buf.index;
392 pkt->priv = buf_descriptor;
394 return s->buf_len[buf.index];
397 static int read_frame(AVFormatContext *ctx, AVPacket *pkt)
402 static int mmap_start(AVFormatContext *ctx)
404 struct video_data *s = ctx->priv_data;
405 enum v4l2_buf_type type;
408 for (i = 0; i < s->buffers; i++) {
409 struct v4l2_buffer buf;
411 memset(&buf, 0, sizeof(struct v4l2_buffer));
412 buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
413 buf.memory = V4L2_MEMORY_MMAP;
416 res = ioctl (s->fd, VIDIOC_QBUF, &buf);
418 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF): %s\n", strerror(errno));
424 type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
425 res = ioctl (s->fd, VIDIOC_STREAMON, &type);
427 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_STREAMON): %s\n", strerror(errno));
435 static void mmap_close(struct video_data *s)
437 enum v4l2_buf_type type;
440 type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
441 /* We do not check for the result, because we could
442 * not do anything about it anyway...
444 ioctl(s->fd, VIDIOC_STREAMOFF, &type);
445 for (i = 0; i < s->buffers; i++) {
446 munmap(s->buf_start[i], s->buf_len[i]);
448 av_free(s->buf_start);
452 static int v4l2_set_parameters( AVFormatContext *s1, AVFormatParameters *ap )
454 struct video_data *s = s1->priv_data;
455 struct v4l2_input input;
456 struct v4l2_standard standard;
460 /* set tv video input */
461 memset (&input, 0, sizeof (input));
462 input.index = ap->channel;
463 if(ioctl (s->fd, VIDIOC_ENUMINPUT, &input) < 0) {
464 av_log(s1, AV_LOG_ERROR, "The V4L2 driver ioctl enum input failed:\n");
468 av_log(s1, AV_LOG_DEBUG, "The V4L2 driver set input_id: %d, input: %s\n",
469 ap->channel, input.name);
470 if(ioctl (s->fd, VIDIOC_S_INPUT, &input.index) < 0 ) {
471 av_log(s1, AV_LOG_ERROR, "The V4L2 driver ioctl set input(%d) failed\n",
478 av_log(s1, AV_LOG_DEBUG, "The V4L2 driver set standard: %s\n",
480 /* set tv standard */
481 memset (&standard, 0, sizeof (standard));
484 if (ioctl(s->fd, VIDIOC_ENUMSTD, &standard) < 0) {
485 av_log(s1, AV_LOG_ERROR, "The V4L2 driver ioctl set standard(%s) failed\n",
490 if(!strcasecmp(standard.name, ap->standard)) {
495 av_log(s1, AV_LOG_DEBUG, "The V4L2 driver set standard: %s, id: %"PRIu64"\n",
496 ap->standard, standard.id);
497 if (ioctl(s->fd, VIDIOC_S_STD, &standard.id) < 0) {
498 av_log(s1, AV_LOG_ERROR, "The V4L2 driver ioctl set standard(%s) failed\n",
507 static int v4l2_read_header(AVFormatContext *s1, AVFormatParameters *ap)
509 struct video_data *s = s1->priv_data;
512 int res, frame_rate, frame_rate_base;
513 uint32_t desired_format, capabilities;
515 if (ap->width <= 0 || ap->height <= 0) {
516 av_log(s1, AV_LOG_ERROR, "Wrong size (%dx%d)\n", ap->width, ap->height);
519 if (ap->time_base.den <= 0) {
520 av_log(s1, AV_LOG_ERROR, "Wrong time base (%d)\n", ap->time_base.den);
526 frame_rate = ap->time_base.den;
527 frame_rate_base = ap->time_base.num;
529 if(avcodec_check_dimensions(s1, ap->width, ap->height) < 0)
532 st = av_new_stream(s1, 0);
534 return AVERROR(ENOMEM);
536 av_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
540 s->frame_rate = frame_rate;
541 s->frame_rate_base = frame_rate_base;
544 s->fd = device_open(s1, &capabilities);
548 av_log(s1, AV_LOG_INFO, "[%d]Capabilities: %x\n", s->fd, capabilities);
550 desired_format = fmt_ff2v4l(ap->pix_fmt);
551 if (desired_format == 0 || (device_init(s1, &width, &height, desired_format) < 0)) {
556 desired_format = fmt_conversion_table[i].v4l2_fmt;
557 if (device_init(s1, &width, &height, desired_format) < 0) {
563 if (i == FF_ARRAY_ELEMS(fmt_conversion_table)) {
568 if (desired_format == 0) {
569 av_log(s1, AV_LOG_ERROR, "Cannot find a proper format.\n");
574 s->frame_format = desired_format;
576 if( v4l2_set_parameters( s1, ap ) < 0 )
579 st->codec->pix_fmt = fmt_v4l2ff(desired_format);
580 s->frame_size = avpicture_get_size(st->codec->pix_fmt, width, height);
581 if (capabilities & V4L2_CAP_STREAMING) {
582 s->io_method = io_mmap;
585 res = mmap_start(s1);
588 s->io_method = io_read;
596 s->top_field_first = first_field(s->fd);
598 st->codec->codec_type = CODEC_TYPE_VIDEO;
599 st->codec->codec_id = CODEC_ID_RAWVIDEO;
600 st->codec->width = width;
601 st->codec->height = height;
602 st->codec->time_base.den = frame_rate;
603 st->codec->time_base.num = frame_rate_base;
604 st->codec->bit_rate = s->frame_size * 1/av_q2d(st->codec->time_base) * 8;
609 static int v4l2_read_packet(AVFormatContext *s1, AVPacket *pkt)
611 struct video_data *s = s1->priv_data;
614 if (s->io_method == io_mmap) {
616 res = mmap_read_frame(s1, pkt);
617 } else if (s->io_method == io_read) {
618 if (av_new_packet(pkt, s->frame_size) < 0)
621 res = read_frame(s1, pkt);
629 if (s1->streams[0]->codec->coded_frame) {
630 s1->streams[0]->codec->coded_frame->interlaced_frame = 1;
631 s1->streams[0]->codec->coded_frame->top_field_first = s->top_field_first;
634 return s->frame_size;
637 static int v4l2_read_close(AVFormatContext *s1)
639 struct video_data *s = s1->priv_data;
641 if (s->io_method == io_mmap) {
649 AVInputFormat v4l2_demuxer = {
651 NULL_IF_CONFIG_SMALL("Video4Linux2 device grab"),
652 sizeof(struct video_data),
657 .flags = AVFMT_NOFILE,