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;
78 static struct fmt_map fmt_conversion_table[] = {
80 .ff_fmt = PIX_FMT_YUV420P,
81 .v4l2_fmt = V4L2_PIX_FMT_YUV420,
84 .ff_fmt = PIX_FMT_YUV422P,
85 .v4l2_fmt = V4L2_PIX_FMT_YUV422P,
88 .ff_fmt = PIX_FMT_YUYV422,
89 .v4l2_fmt = V4L2_PIX_FMT_YUYV,
92 .ff_fmt = PIX_FMT_UYVY422,
93 .v4l2_fmt = V4L2_PIX_FMT_UYVY,
96 .ff_fmt = PIX_FMT_YUV411P,
97 .v4l2_fmt = V4L2_PIX_FMT_YUV411P,
100 .ff_fmt = PIX_FMT_YUV410P,
101 .v4l2_fmt = V4L2_PIX_FMT_YUV410,
104 .ff_fmt = PIX_FMT_RGB555,
105 .v4l2_fmt = V4L2_PIX_FMT_RGB555,
108 .ff_fmt = PIX_FMT_RGB565,
109 .v4l2_fmt = V4L2_PIX_FMT_RGB565,
112 .ff_fmt = PIX_FMT_BGR24,
113 .v4l2_fmt = V4L2_PIX_FMT_BGR24,
116 .ff_fmt = PIX_FMT_RGB24,
117 .v4l2_fmt = V4L2_PIX_FMT_RGB24,
120 .ff_fmt = PIX_FMT_BGRA,
121 .v4l2_fmt = V4L2_PIX_FMT_BGR32,
124 .ff_fmt = PIX_FMT_GRAY8,
125 .v4l2_fmt = V4L2_PIX_FMT_GREY,
129 static int device_open(AVFormatContext *ctx, uint32_t *capabilities)
131 struct v4l2_capability cap;
136 if (ctx->flags & AVFMT_FLAG_NONBLOCK) {
139 fd = open(ctx->filename, flags, 0);
141 av_log(ctx, AV_LOG_ERROR, "Cannot open video device %s : %s\n",
142 ctx->filename, strerror(errno));
147 res = ioctl(fd, VIDIOC_QUERYCAP, &cap);
148 // ENOIOCTLCMD definition only availble on __KERNEL__
149 if (res < 0 && errno == 515)
151 av_log(ctx, AV_LOG_ERROR, "QUERYCAP not implemented, probably V4L device but not supporting V4L2\n");
157 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYCAP): %s\n",
163 if ((cap.capabilities & V4L2_CAP_VIDEO_CAPTURE) == 0) {
164 av_log(ctx, AV_LOG_ERROR, "Not a video capture device\n");
169 *capabilities = cap.capabilities;
174 static int device_init(AVFormatContext *ctx, int *width, int *height, int pix_fmt)
176 struct video_data *s = ctx->priv_data;
178 struct v4l2_format fmt;
181 memset(&fmt, 0, sizeof(struct v4l2_format));
182 fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
183 fmt.fmt.pix.width = *width;
184 fmt.fmt.pix.height = *height;
185 fmt.fmt.pix.pixelformat = pix_fmt;
186 fmt.fmt.pix.field = V4L2_FIELD_INTERLACED;
187 res = ioctl(fd, VIDIOC_S_FMT, &fmt);
188 if ((*width != fmt.fmt.pix.width) || (*height != fmt.fmt.pix.height)) {
189 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);
190 *width = fmt.fmt.pix.width;
191 *height = fmt.fmt.pix.height;
194 if (pix_fmt != fmt.fmt.pix.pixelformat) {
195 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);
202 static int first_field(int fd)
207 res = ioctl(fd, VIDIOC_G_STD, &std);
211 if (std & V4L2_STD_NTSC) {
218 static uint32_t fmt_ff2v4l(enum PixelFormat pix_fmt)
222 for (i = 0; i < FF_ARRAY_ELEMS(fmt_conversion_table); i++) {
223 if (fmt_conversion_table[i].ff_fmt == pix_fmt) {
224 return fmt_conversion_table[i].v4l2_fmt;
231 static enum PixelFormat fmt_v4l2ff(uint32_t pix_fmt)
235 for (i = 0; i < FF_ARRAY_ELEMS(fmt_conversion_table); i++) {
236 if (fmt_conversion_table[i].v4l2_fmt == pix_fmt) {
237 return fmt_conversion_table[i].ff_fmt;
244 static int mmap_init(AVFormatContext *ctx)
246 struct video_data *s = ctx->priv_data;
247 struct v4l2_requestbuffers req;
250 memset(&req, 0, sizeof(struct v4l2_requestbuffers));
251 req.count = desired_video_buffers;
252 req.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
253 req.memory = V4L2_MEMORY_MMAP;
254 res = ioctl (s->fd, VIDIOC_REQBUFS, &req);
256 if (errno == EINVAL) {
257 av_log(ctx, AV_LOG_ERROR, "Device does not support mmap\n");
259 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_REQBUFS)\n");
266 av_log(ctx, AV_LOG_ERROR, "Insufficient buffer memory\n");
270 s->buffers = req.count;
271 s->buf_start = av_malloc(sizeof(void *) * s->buffers);
272 if (s->buf_start == NULL) {
273 av_log(ctx, AV_LOG_ERROR, "Cannot allocate buffer pointers\n");
277 s->buf_len = av_malloc(sizeof(unsigned int) * s->buffers);
278 if (s->buf_len == NULL) {
279 av_log(ctx, AV_LOG_ERROR, "Cannot allocate buffer sizes\n");
280 av_free(s->buf_start);
285 for (i = 0; i < req.count; i++) {
286 struct v4l2_buffer buf;
288 memset(&buf, 0, sizeof(struct v4l2_buffer));
289 buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
290 buf.memory = V4L2_MEMORY_MMAP;
292 res = ioctl (s->fd, VIDIOC_QUERYBUF, &buf);
294 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYBUF)\n");
299 s->buf_len[i] = buf.length;
300 if (s->buf_len[i] < s->frame_size) {
301 av_log(ctx, AV_LOG_ERROR, "Buffer len [%d] = %d != %d\n", i, s->buf_len[i], s->frame_size);
305 s->buf_start[i] = mmap (NULL, buf.length,
306 PROT_READ | PROT_WRITE, MAP_SHARED, s->fd, buf.m.offset);
307 if (s->buf_start[i] == MAP_FAILED) {
308 av_log(ctx, AV_LOG_ERROR, "mmap: %s\n", strerror(errno));
317 static int read_init(AVFormatContext *ctx)
322 static void mmap_release_buffer(AVPacket *pkt)
324 struct v4l2_buffer buf;
326 struct buff_data *buf_descriptor = pkt->priv;
328 memset(&buf, 0, sizeof(struct v4l2_buffer));
329 buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
330 buf.memory = V4L2_MEMORY_MMAP;
331 buf.index = buf_descriptor->index;
332 fd = buf_descriptor->fd;
333 av_free(buf_descriptor);
335 res = ioctl (fd, VIDIOC_QBUF, &buf);
337 av_log(NULL, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF)\n");
343 static int mmap_read_frame(AVFormatContext *ctx, AVPacket *pkt)
345 struct video_data *s = ctx->priv_data;
346 struct v4l2_buffer buf;
347 struct buff_data *buf_descriptor;
350 memset(&buf, 0, sizeof(struct v4l2_buffer));
351 buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
352 buf.memory = V4L2_MEMORY_MMAP;
354 /* FIXME: Some special treatment might be needed in case of loss of signal... */
355 while ((res = ioctl(s->fd, VIDIOC_DQBUF, &buf)) < 0 && (errno == EINTR));
357 if (errno == EAGAIN) {
360 return AVERROR(EAGAIN);
362 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_DQBUF): %s\n", strerror(errno));
366 assert (buf.index < s->buffers);
367 if (buf.bytesused != s->frame_size) {
368 av_log(ctx, AV_LOG_ERROR, "The v4l2 frame is %d bytes, but %d bytes are expected\n", buf.bytesused, s->frame_size);
373 /* Image is at s->buff_start[buf.index] */
374 pkt->data= s->buf_start[buf.index];
375 pkt->size = buf.bytesused;
376 pkt->pts = buf.timestamp.tv_sec * INT64_C(1000000) + buf.timestamp.tv_usec;
377 pkt->destruct = mmap_release_buffer;
378 buf_descriptor = av_malloc(sizeof(struct buff_data));
379 if (buf_descriptor == NULL) {
380 /* Something went wrong... Since av_malloc() failed, we cannot even
381 * allocate a buffer for memcopying into it
383 av_log(ctx, AV_LOG_ERROR, "Failed to allocate a buffer descriptor\n");
384 res = ioctl (s->fd, VIDIOC_QBUF, &buf);
388 buf_descriptor->fd = s->fd;
389 buf_descriptor->index = buf.index;
390 pkt->priv = buf_descriptor;
392 return s->buf_len[buf.index];
395 static int read_frame(AVFormatContext *ctx, AVPacket *pkt)
400 static int mmap_start(AVFormatContext *ctx)
402 struct video_data *s = ctx->priv_data;
403 enum v4l2_buf_type type;
406 for (i = 0; i < s->buffers; i++) {
407 struct v4l2_buffer buf;
409 memset(&buf, 0, sizeof(struct v4l2_buffer));
410 buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
411 buf.memory = V4L2_MEMORY_MMAP;
414 res = ioctl (s->fd, VIDIOC_QBUF, &buf);
416 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF): %s\n", strerror(errno));
422 type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
423 res = ioctl (s->fd, VIDIOC_STREAMON, &type);
425 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_STREAMON): %s\n", strerror(errno));
433 static void mmap_close(struct video_data *s)
435 enum v4l2_buf_type type;
438 type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
439 /* We do not check for the result, because we could
440 * not do anything about it anyway...
442 ioctl(s->fd, VIDIOC_STREAMOFF, &type);
443 for (i = 0; i < s->buffers; i++) {
444 munmap(s->buf_start[i], s->buf_len[i]);
446 av_free(s->buf_start);
450 static int v4l2_set_parameters( AVFormatContext *s1, AVFormatParameters *ap )
452 struct video_data *s = s1->priv_data;
453 struct v4l2_input input;
454 struct v4l2_standard standard;
458 /* set tv video input */
459 memset (&input, 0, sizeof (input));
460 input.index = ap->channel;
461 if(ioctl (s->fd, VIDIOC_ENUMINPUT, &input) < 0) {
462 av_log(s1, AV_LOG_ERROR, "The V4L2 driver ioctl enum input failed:\n");
466 av_log(s1, AV_LOG_DEBUG, "The V4L2 driver set input_id: %d, input: %s\n",
467 ap->channel, input.name);
468 if(ioctl (s->fd, VIDIOC_S_INPUT, &input.index) < 0 ) {
469 av_log(s1, AV_LOG_ERROR, "The V4L2 driver ioctl set input(%d) failed\n",
476 av_log(s1, AV_LOG_DEBUG, "The V4L2 driver set standard: %s\n",
478 /* set tv standard */
479 memset (&standard, 0, sizeof (standard));
482 if (ioctl(s->fd, VIDIOC_ENUMSTD, &standard) < 0) {
483 av_log(s1, AV_LOG_ERROR, "The V4L2 driver ioctl set standard(%s) failed\n",
488 if(!strcasecmp(standard.name, ap->standard)) {
493 av_log(s1, AV_LOG_DEBUG, "The V4L2 driver set standard: %s, id: %"PRIu64"\n",
494 ap->standard, standard.id);
495 if (ioctl(s->fd, VIDIOC_S_STD, &standard.id) < 0) {
496 av_log(s1, AV_LOG_ERROR, "The V4L2 driver ioctl set standard(%s) failed\n",
505 static int v4l2_read_header(AVFormatContext *s1, AVFormatParameters *ap)
507 struct video_data *s = s1->priv_data;
511 uint32_t desired_format, capabilities;
513 if (ap->width <= 0 || ap->height <= 0) {
514 av_log(s1, AV_LOG_ERROR, "Wrong size (%dx%d)\n", ap->width, ap->height);
521 if(avcodec_check_dimensions(s1, ap->width, ap->height) < 0)
524 st = av_new_stream(s1, 0);
526 return AVERROR(ENOMEM);
528 av_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
534 s->fd = device_open(s1, &capabilities);
538 av_log(s1, AV_LOG_INFO, "[%d]Capabilities: %x\n", s->fd, capabilities);
540 desired_format = fmt_ff2v4l(ap->pix_fmt);
541 if (desired_format == 0 || (device_init(s1, &width, &height, desired_format) < 0)) {
546 desired_format = fmt_conversion_table[i].v4l2_fmt;
547 if (device_init(s1, &width, &height, desired_format) < 0) {
553 if (i == FF_ARRAY_ELEMS(fmt_conversion_table)) {
558 if (desired_format == 0) {
559 av_log(s1, AV_LOG_ERROR, "Cannot find a proper format.\n");
564 s->frame_format = desired_format;
566 if( v4l2_set_parameters( s1, ap ) < 0 )
569 st->codec->pix_fmt = fmt_v4l2ff(desired_format);
570 s->frame_size = avpicture_get_size(st->codec->pix_fmt, width, height);
571 if (capabilities & V4L2_CAP_STREAMING) {
572 s->io_method = io_mmap;
575 res = mmap_start(s1);
578 s->io_method = io_read;
586 s->top_field_first = first_field(s->fd);
588 st->codec->codec_type = CODEC_TYPE_VIDEO;
589 st->codec->codec_id = CODEC_ID_RAWVIDEO;
590 st->codec->width = width;
591 st->codec->height = height;
592 st->codec->time_base.den = ap->time_base.den;
593 st->codec->time_base.num = ap->time_base.num;
594 st->codec->bit_rate = s->frame_size * 1/av_q2d(st->codec->time_base) * 8;
599 static int v4l2_read_packet(AVFormatContext *s1, AVPacket *pkt)
601 struct video_data *s = s1->priv_data;
604 if (s->io_method == io_mmap) {
606 res = mmap_read_frame(s1, pkt);
607 } else if (s->io_method == io_read) {
608 if (av_new_packet(pkt, s->frame_size) < 0)
611 res = read_frame(s1, pkt);
619 if (s1->streams[0]->codec->coded_frame) {
620 s1->streams[0]->codec->coded_frame->interlaced_frame = 1;
621 s1->streams[0]->codec->coded_frame->top_field_first = s->top_field_first;
624 return s->frame_size;
627 static int v4l2_read_close(AVFormatContext *s1)
629 struct video_data *s = s1->priv_data;
631 if (s->io_method == io_mmap) {
639 AVInputFormat v4l2_demuxer = {
641 NULL_IF_CONFIG_SMALL("Video4Linux2 device grab"),
642 sizeof(struct video_data),
647 .flags = AVFMT_NOFILE,