FFmpeg/libavformat/v4l2.c
Luca Abeni 7c7e7464e3 Make read_packet fail is the v4l2 driver returns an unexpected frame size
(driver's bug? If not, we will have to support this in some way)

Originally committed as revision 6756 to svn://svn.ffmpeg.org/ffmpeg/trunk
2006-10-22 09:56:08 +00:00

542 lines
14 KiB
C

/*
* Video4Linux2 grab interface
* Copyright (c) 2000,2001 Fabrice Bellard.
* Copyright (c) 2006 Luca Abeni.
*
* Part of this file is based on the V4L2 video capture example
* (http://v4l2spec.bytesex.org/v4l2spec/capture.c)
*
* Thanks to Michael Niedermayer for providing the mapping between
* V4L2_PIX_FMT_* and PIX_FMT_*
*
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "avformat.h"
#include <unistd.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <sys/time.h>
#include <asm/types.h>
#include <linux/videodev2.h>
#include <time.h>
static const int desired_video_buffers = 256;
enum io_method {
io_read,
io_mmap,
io_userptr
};
struct video_data {
int fd;
int frame_format; /* V4L2_PIX_FMT_* */
enum io_method io_method;
int width, height;
int frame_rate;
int frame_rate_base;
int frame_size;
int top_field_first;
int buffers;
void **buf_start;
unsigned int *buf_len;
};
struct fmt_map {
enum PixelFormat ff_fmt;
int32_t v4l2_fmt;
};
static struct fmt_map fmt_conversion_table[] = {
{
.ff_fmt = PIX_FMT_YUV420P,
.v4l2_fmt = V4L2_PIX_FMT_YUV420,
},
{
.ff_fmt = PIX_FMT_YUV422P,
.v4l2_fmt = V4L2_PIX_FMT_YUV422P,
},
{
.ff_fmt = PIX_FMT_YUV422,
.v4l2_fmt = V4L2_PIX_FMT_YUYV,
},
{
.ff_fmt = PIX_FMT_UYVY422,
.v4l2_fmt = V4L2_PIX_FMT_UYVY,
},
{
.ff_fmt = PIX_FMT_YUV411P,
.v4l2_fmt = V4L2_PIX_FMT_YUV411P,
},
{
.ff_fmt = PIX_FMT_YUV410P,
.v4l2_fmt = V4L2_PIX_FMT_YUV410,
},
{
.ff_fmt = PIX_FMT_BGR24,
.v4l2_fmt = V4L2_PIX_FMT_BGR24,
},
{
.ff_fmt = PIX_FMT_RGB24,
.v4l2_fmt = V4L2_PIX_FMT_RGB24,
},
/*
{
.ff_fmt = PIX_FMT_RGBA32,
.v4l2_fmt = V4L2_PIX_FMT_BGR32,
},
*/
{
.ff_fmt = PIX_FMT_GRAY8,
.v4l2_fmt = V4L2_PIX_FMT_GREY,
},
};
static int device_open(const char *devname, uint32_t *capabilities)
{
struct v4l2_capability cap;
int fd;
int res;
fd = open(devname, O_RDWR /*| O_NONBLOCK*/, 0);
if (fd < 0) {
av_log(NULL, AV_LOG_ERROR, "Cannot open video device %s : %s\n",
devname, strerror(errno));
return -1;
}
res = ioctl(fd, VIDIOC_QUERYCAP, &cap);
// ENOIOCTLCMD definition only availble on __KERNEL__
if (res < 0 && errno == 515)
{
av_log(NULL, AV_LOG_ERROR, "QUERYCAP not implemented, probably V4L device but not supporting V4L2\n");
close(fd);
return -1;
}
if (res < 0) {
av_log(NULL, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYCAP): %s\n",
strerror(errno));
close(fd);
return -1;
}
if ((cap.capabilities & V4L2_CAP_VIDEO_CAPTURE) == 0) {
av_log(NULL, AV_LOG_ERROR, "Not a video capture device\n");
close(fd);
return -1;
}
*capabilities = cap.capabilities;
return fd;
}
static int device_init(int fd, int *width, int *height, int pix_fmt)
{
struct v4l2_format fmt;
int res;
memset(&fmt, 0, sizeof(struct v4l2_format));
fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
fmt.fmt.pix.width = *width;
fmt.fmt.pix.height = *height;
fmt.fmt.pix.pixelformat = pix_fmt;
fmt.fmt.pix.field = V4L2_FIELD_INTERLACED;
res = ioctl(fd, VIDIOC_S_FMT, &fmt);
if ((*width != fmt.fmt.pix.width) || (*height != fmt.fmt.pix.height)) {
av_log(NULL, 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);
*width = fmt.fmt.pix.width;
*height = fmt.fmt.pix.height;
}
return res;
}
static int first_field(int fd)
{
int res;
v4l2_std_id std;
res = ioctl(fd, VIDIOC_G_STD, &std);
if (res < 0) {
return 0;
}
if (std & V4L2_STD_NTSC) {
return 0;
}
return 1;
}
static uint32_t fmt_ff2v4l(enum PixelFormat pix_fmt)
{
int i;
for (i = 0; i < sizeof(fmt_conversion_table) / sizeof(struct fmt_map); i++) {
if (fmt_conversion_table[i].ff_fmt == pix_fmt) {
return fmt_conversion_table[i].v4l2_fmt;
}
}
return 0;
}
static enum PixelFormat fmt_v4l2ff(uint32_t pix_fmt)
{
int i;
for (i = 0; i < sizeof(fmt_conversion_table) / sizeof(struct fmt_map); i++) {
if (fmt_conversion_table[i].v4l2_fmt == pix_fmt) {
return fmt_conversion_table[i].ff_fmt;
}
}
return -1;
}
static int mmap_init(struct video_data *s)
{
struct v4l2_requestbuffers req;
int i, res;
memset(&req, 0, sizeof(struct v4l2_requestbuffers));
req.count = desired_video_buffers;
req.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
req.memory = V4L2_MEMORY_MMAP;
res = ioctl (s->fd, VIDIOC_REQBUFS, &req);
if (res < 0) {
if (errno == EINVAL) {
av_log(NULL, AV_LOG_ERROR, "Device does not support mmap\n");
} else {
av_log(NULL, AV_LOG_ERROR, "ioctl(VIDIOC_REQBUFS)\n");
}
return -1;
}
if (req.count < 2) {
av_log(NULL, AV_LOG_ERROR, "Insufficient buffer memory\n");
return -1;
}
s->buffers = req.count;
s->buf_start = av_malloc(sizeof(void *) * s->buffers);
if (s->buf_start == NULL) {
av_log(NULL, AV_LOG_ERROR, "Cannot allocate buffer pointers\n");
return -1;
}
s->buf_len = av_malloc(sizeof(unsigned int) * s->buffers);
if (s->buf_len == NULL) {
av_log(NULL, AV_LOG_ERROR, "Cannot allocate buffer sizes\n");
av_free(s->buf_start);
return -1;
}
for (i = 0; i < req.count; i++) {
struct v4l2_buffer buf;
memset(&buf, 0, sizeof(struct v4l2_buffer));
buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
buf.memory = V4L2_MEMORY_MMAP;
buf.index = i;
res = ioctl (s->fd, VIDIOC_QUERYBUF, &buf);
if (res < 0) {
av_log(NULL, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYBUF)\n");
return -1;
}
s->buf_len[i] = buf.length;
if (s->buf_len[i] < s->frame_size) {
av_log(NULL, AV_LOG_ERROR, "Buffer len [%d] = %d != %d\n", i, s->buf_len[i], s->frame_size);
return -1;
}
s->buf_start[i] = mmap (NULL, buf.length,
PROT_READ | PROT_WRITE, MAP_SHARED, s->fd, buf.m.offset);
if (s->buf_start[i] == MAP_FAILED) {
av_log(NULL, AV_LOG_ERROR, "mmap: %s\n", strerror(errno));
return -1;
}
}
return 0;
}
static int read_init(struct video_data *s)
{
return -1;
}
static int mmap_read_frame(struct video_data *s, void *frame, int64_t *ts)
{
struct v4l2_buffer buf;
int res;
memset(&buf, 0, sizeof(struct v4l2_buffer));
buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
buf.memory = V4L2_MEMORY_MMAP;
/* FIXME: Some special treatment might be needed in case of loss of signal... */
while ((res = ioctl(s->fd, VIDIOC_DQBUF, &buf)) < 0 &&
((errno == EAGAIN) || (errno == EINTR)));
if (res < 0) {
av_log(NULL, AV_LOG_ERROR, "ioctl(VIDIOC_DQBUF): %s\n", strerror(errno));
return -1;
}
assert (buf.index < s->buffers);
if (buf.bytesused != s->frame_size) {
av_log(NULL, AV_LOG_ERROR, "The v4l2 frame is %d bytes, but %d bytes are expected\n", buf.bytesused, s->frame_size);
return -1;
}
/* Image is at s->buff_start[buf.index] */
memcpy(frame, s->buf_start[buf.index], buf.bytesused);
*ts = buf.timestamp.tv_sec * int64_t_C(1000000) + buf.timestamp.tv_usec;
res = ioctl (s->fd, VIDIOC_QBUF, &buf);
if (res < 0) {
av_log(NULL, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF)\n");
return -1;
}
return s->buf_len[buf.index];
}
static int read_frame(struct video_data *s, void *frame, int64_t *ts)
{
return -1;
}
static int mmap_start(struct video_data *s)
{
enum v4l2_buf_type type;
int i, res;
for (i = 0; i < s->buffers; i++) {
struct v4l2_buffer buf;
memset(&buf, 0, sizeof(struct v4l2_buffer));
buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
buf.memory = V4L2_MEMORY_MMAP;
buf.index = i;
res = ioctl (s->fd, VIDIOC_QBUF, &buf);
if (res < 0) {
av_log(NULL, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF): %s\n", strerror(errno));
return -1;
}
}
type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
res = ioctl (s->fd, VIDIOC_STREAMON, &type);
if (res < 0) {
av_log(NULL, AV_LOG_ERROR, "ioctl(VIDIOC_STREAMON): %s\n", strerror(errno));
return -1;
}
return 0;
}
static void mmap_close(struct video_data *s)
{
enum v4l2_buf_type type;
int i;
type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
/* We do not check for the result, because we could
* not do anything about it anyway...
*/
ioctl(s->fd, VIDIOC_STREAMOFF, &type);
for (i = 0; i < s->buffers; i++) {
munmap(s->buf_start[i], s->buf_len[i]);
}
av_free(s->buf_start);
av_free(s->buf_len);
}
static int v4l2_read_header(AVFormatContext *s1, AVFormatParameters *ap)
{
struct video_data *s = s1->priv_data;
AVStream *st;
int width, height;
int res, frame_rate, frame_rate_base;
uint32_t desired_format, capabilities;
const char *video_device;
if (ap->width <= 0 || ap->height <= 0 || ap->time_base.den <= 0) {
av_log(s1, AV_LOG_ERROR, "Missing/Wrong parameters\n");
return -1;
}
width = ap->width;
height = ap->height;
frame_rate = ap->time_base.den;
frame_rate_base = ap->time_base.num;
if((unsigned)width > 32767 || (unsigned)height > 32767) {
av_log(s1, AV_LOG_ERROR, "Wrong size %dx%d\n", width, height);
return -1;
}
st = av_new_stream(s1, 0);
if (!st) {
return -ENOMEM;
}
av_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
s->width = width;
s->height = height;
s->frame_rate = frame_rate;
s->frame_rate_base = frame_rate_base;
video_device = ap->device;
if (!video_device) {
video_device = "/dev/video";
}
capabilities = 0;
s->fd = device_open(video_device, &capabilities);
if (s->fd < 0) {
av_free(st);
return AVERROR_IO;
}
av_log(s1, AV_LOG_INFO, "[%d]Capabilities: %x\n", s->fd, capabilities);
desired_format = fmt_ff2v4l(ap->pix_fmt);
if (desired_format == 0 || (device_init(s->fd, &width, &height, desired_format) < 0)) {
int i, done;
done = 0; i = 0;
while (!done) {
desired_format = fmt_conversion_table[i].v4l2_fmt;
if (device_init(s->fd, &width, &height, desired_format) < 0) {
desired_format = 0;
i++;
} else {
done = 1;
}
if (i == sizeof(fmt_conversion_table) / sizeof(struct fmt_map)) {
done = 1;
}
}
}
if (desired_format == 0) {
av_log(s1, AV_LOG_ERROR, "Cannot find a proper format.\n");
close(s->fd);
av_free(st);
return AVERROR_IO;
}
s->frame_format = desired_format;
st->codec->pix_fmt = fmt_v4l2ff(desired_format);
s->frame_size = avpicture_get_size(st->codec->pix_fmt, width, height);
if (capabilities & V4L2_CAP_STREAMING) {
s->io_method = io_mmap;
res = mmap_init(s);
if (res == 0) {
res = mmap_start(s);
}
} else {
s->io_method = io_read;
res = read_init(s);
}
if (res < 0) {
close(s->fd);
av_free(st);
return AVERROR_IO;
}
s->top_field_first = first_field(s->fd);
st->codec->codec_type = CODEC_TYPE_VIDEO;
st->codec->codec_id = CODEC_ID_RAWVIDEO;
st->codec->width = width;
st->codec->height = height;
st->codec->time_base.den = frame_rate;
st->codec->time_base.num = frame_rate_base;
st->codec->bit_rate = s->frame_size * 1/av_q2d(st->codec->time_base) * 8;
return 0;
}
static int v4l2_read_packet(AVFormatContext *s1, AVPacket *pkt)
{
struct video_data *s = s1->priv_data;
int res;
if (av_new_packet(pkt, s->frame_size) < 0)
return AVERROR_IO;
if (s->io_method == io_mmap) {
res = mmap_read_frame(s, pkt->data, &pkt->pts);
} else if (s->io_method == io_read) {
res = read_frame(s, pkt->data, &pkt->pts);
} else {
return AVERROR_IO;
}
if (res < 0) {
return AVERROR_IO;
}
if (s1->streams[0]->codec->coded_frame) {
s1->streams[0]->codec->coded_frame->interlaced_frame = 1;
s1->streams[0]->codec->coded_frame->top_field_first = s->top_field_first;
}
return s->frame_size;
}
static int v4l2_read_close(AVFormatContext *s1)
{
struct video_data *s = s1->priv_data;
if (s->io_method == io_mmap) {
mmap_close(s);
}
close(s->fd);
return 0;
}
AVInputFormat v4l2_demuxer = {
"video4linux2",
"video grab",
sizeof(struct video_data),
NULL,
v4l2_read_header,
v4l2_read_packet,
v4l2_read_close,
.flags = AVFMT_NOFILE,
};