RepoMirrors/ffmpeg
1
0
Fork 0
mirror of https://git.ffmpeg.org/ffmpeg.git synced 2024-12-14 03:04:53 +00:00
Code Issues Projects Releases Wiki Activity
29ba091136
ffmpeg/libavdevice/v4l2.c
Reinhard Tartler 737eb5976f Merge libavcore into libavutil 
It is pretty hopeless that other considerable projects will adopt
libavutil alone in other projects. Projects that need small footprint
are better off with more specialized libraries such as gnulib or rather
just copy the necessary parts that they need. With this in mind, nobody
is helped by having libavutil and libavcore split. In order to ease
maintenance inside and around FFmpeg and to reduce confusion where to
put common code, avcore's functionality is merged (back) to avutil.

Signed-off-by: Reinhard Tartler <siretart@tauware.de>
2011-02-15 16:18:21 +01:00

693 lines
20 KiB
C
Raw Blame History

/*
* 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
*/
#undef __STRICT_ANSI__ //workaround due to broken kernel headers
#include "config.h"
#include "libavformat/avformat.h"
#include <unistd.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <sys/time.h>
#if HAVE_SYS_VIDEOIO_H
#include <sys/videoio.h>
#else
#include <asm/types.h>
#include <linux/videodev2.h>
#endif
#include <time.h>
#include <strings.h>
#include "libavutil/imgutils.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_size;
int top_field_first;
int buffers;
void **buf_start;
unsigned int *buf_len;
};
struct buff_data {
int index;
int fd;
};
struct fmt_map {
enum PixelFormat ff_fmt;
enum CodecID codec_id;
uint32_t v4l2_fmt;
};
static struct fmt_map fmt_conversion_table[] = {
//ff_fmt codec_id v4l2_fmt
{ PIX_FMT_YUV420P, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_YUV420 },
{ PIX_FMT_YUV422P, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_YUV422P },
{ PIX_FMT_YUYV422, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_YUYV },
{ PIX_FMT_UYVY422, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_UYVY },
{ PIX_FMT_YUV411P, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_YUV411P },
{ PIX_FMT_YUV410P, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_YUV410 },
{ PIX_FMT_RGB555, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_RGB555 },
{ PIX_FMT_RGB565, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_RGB565 },
{ PIX_FMT_BGR24, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_BGR24 },
{ PIX_FMT_RGB24, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_RGB24 },
{ PIX_FMT_BGRA, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_BGR32 },
{ PIX_FMT_GRAY8, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_GREY },
{ PIX_FMT_NV12, CODEC_ID_RAWVIDEO, V4L2_PIX_FMT_NV12 },
{ PIX_FMT_NONE, CODEC_ID_MJPEG, V4L2_PIX_FMT_MJPEG },
{ PIX_FMT_NONE, CODEC_ID_MJPEG, V4L2_PIX_FMT_JPEG },
};
static int device_open(AVFormatContext *ctx, uint32_t *capabilities)
{
struct v4l2_capability cap;
int fd;
int res, err;
int flags = O_RDWR;
if (ctx->flags & AVFMT_FLAG_NONBLOCK) {
flags |= O_NONBLOCK;
}
fd = open(ctx->filename, flags, 0);
if (fd < 0) {
av_log(ctx, AV_LOG_ERROR, "Cannot open video device %s : %s\n",
ctx->filename, strerror(errno));
return AVERROR(errno);
}
res = ioctl(fd, VIDIOC_QUERYCAP, &cap);
// ENOIOCTLCMD definition only availble on __KERNEL__
if (res < 0 && ((err = errno) == 515)) {
av_log(ctx, AV_LOG_ERROR, "QUERYCAP not implemented, probably V4L device but not supporting V4L2\n");
close(fd);
return AVERROR(515);
}
if (res < 0) {
av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYCAP): %s\n",
strerror(errno));
close(fd);
return AVERROR(err);
}
if ((cap.capabilities & V4L2_CAP_VIDEO_CAPTURE) == 0) {
av_log(ctx, AV_LOG_ERROR, "Not a video capture device\n");
close(fd);
return AVERROR(ENODEV);
}
*capabilities = cap.capabilities;
return fd;
}
static int device_init(AVFormatContext *ctx, int *width, int *height, uint32_t pix_fmt)
{
struct video_data *s = ctx->priv_data;
int fd = s->fd;
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(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);
*width = fmt.fmt.pix.width;
*height = fmt.fmt.pix.height;
}
if (pix_fmt != fmt.fmt.pix.pixelformat) {
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);
res = -1;
}
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, enum CodecID codec_id)
{
int i;
for (i = 0; i < FF_ARRAY_ELEMS(fmt_conversion_table); i++) {
if ((codec_id == CODEC_ID_NONE ||
fmt_conversion_table[i].codec_id == codec_id) &&
(pix_fmt == PIX_FMT_NONE ||
fmt_conversion_table[i].ff_fmt == pix_fmt)) {
return fmt_conversion_table[i].v4l2_fmt;
}
}
return 0;
}
static enum PixelFormat fmt_v4l2ff(uint32_t v4l2_fmt, enum CodecID codec_id)
{
int i;
for (i = 0; i < FF_ARRAY_ELEMS(fmt_conversion_table); i++) {
if (fmt_conversion_table[i].v4l2_fmt == v4l2_fmt &&
fmt_conversion_table[i].codec_id == codec_id) {
return fmt_conversion_table[i].ff_fmt;
}
}
return PIX_FMT_NONE;
}
static enum CodecID fmt_v4l2codec(uint32_t v4l2_fmt)
{
int i;
for (i = 0; i < FF_ARRAY_ELEMS(fmt_conversion_table); i++) {
if (fmt_conversion_table[i].v4l2_fmt == v4l2_fmt) {
return fmt_conversion_table[i].codec_id;
}
}
return CODEC_ID_NONE;
}
static int mmap_init(AVFormatContext *ctx)
{
struct video_data *s = ctx->priv_data;
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(ctx, AV_LOG_ERROR, "Device does not support mmap\n");
} else {
av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_REQBUFS)\n");
}
return AVERROR(errno);
}
if (req.count < 2) {
av_log(ctx, AV_LOG_ERROR, "Insufficient buffer memory\n");
return AVERROR(ENOMEM);
}
s->buffers = req.count;
s->buf_start = av_malloc(sizeof(void *) * s->buffers);
if (s->buf_start == NULL) {
av_log(ctx, AV_LOG_ERROR, "Cannot allocate buffer pointers\n");
return AVERROR(ENOMEM);
}
s->buf_len = av_malloc(sizeof(unsigned int) * s->buffers);
if (s->buf_len == NULL) {
av_log(ctx, AV_LOG_ERROR, "Cannot allocate buffer sizes\n");
av_free(s->buf_start);
return AVERROR(ENOMEM);
}
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(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYBUF)\n");
return AVERROR(errno);
}
s->buf_len[i] = buf.length;
if (s->frame_size > 0 && s->buf_len[i] < s->frame_size) {
av_log(ctx, 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(ctx, AV_LOG_ERROR, "mmap: %s\n", strerror(errno));
return AVERROR(errno);
}
}
return 0;
}
static int read_init(AVFormatContext *ctx)
{
return -1;
}
static void mmap_release_buffer(AVPacket *pkt)
{
struct v4l2_buffer buf;
int res, fd;
struct buff_data *buf_descriptor = pkt->priv;
if (pkt->data == NULL) {
return;
}
memset(&buf, 0, sizeof(struct v4l2_buffer));
buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
buf.memory = V4L2_MEMORY_MMAP;
buf.index = buf_descriptor->index;
fd = buf_descriptor->fd;
av_free(buf_descriptor);
res = ioctl(fd, VIDIOC_QBUF, &buf);
if (res < 0) {
av_log(NULL, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF): %s\n", strerror(errno));
}
pkt->data = NULL;
pkt->size = 0;
}
static int mmap_read_frame(AVFormatContext *ctx, AVPacket *pkt)
{
struct video_data *s = ctx->priv_data;
struct v4l2_buffer buf;
struct buff_data *buf_descriptor;
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 == EINTR));
if (res < 0) {
if (errno == EAGAIN) {
pkt->size = 0;
return AVERROR(EAGAIN);
}
av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_DQBUF): %s\n", strerror(errno));
return AVERROR(errno);
}
assert (buf.index < s->buffers);
if (s->frame_size > 0 && buf.bytesused != s->frame_size) {
av_log(ctx, AV_LOG_ERROR, "The v4l2 frame is %d bytes, but %d bytes are expected\n", buf.bytesused, s->frame_size);
return AVERROR_INVALIDDATA;
}
/* Image is at s->buff_start[buf.index] */
pkt->data= s->buf_start[buf.index];
pkt->size = buf.bytesused;
pkt->pts = buf.timestamp.tv_sec * INT64_C(1000000) + buf.timestamp.tv_usec;
pkt->destruct = mmap_release_buffer;
buf_descriptor = av_malloc(sizeof(struct buff_data));
if (buf_descriptor == NULL) {
/* Something went wrong... Since av_malloc() failed, we cannot even
* allocate a buffer for memcopying into it
*/
av_log(ctx, AV_LOG_ERROR, "Failed to allocate a buffer descriptor\n");
res = ioctl(s->fd, VIDIOC_QBUF, &buf);
return AVERROR(ENOMEM);
}
buf_descriptor->fd = s->fd;
buf_descriptor->index = buf.index;
pkt->priv = buf_descriptor;
return s->buf_len[buf.index];
}
static int read_frame(AVFormatContext *ctx, AVPacket *pkt)
{
return -1;
}
static int mmap_start(AVFormatContext *ctx)
{
struct video_data *s = ctx->priv_data;
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(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF): %s\n", strerror(errno));
return AVERROR(errno);
}
}
type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
res = ioctl(s->fd, VIDIOC_STREAMON, &type);
if (res < 0) {
av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_STREAMON): %s\n", strerror(errno));
return AVERROR(errno);
}
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_set_parameters(AVFormatContext *s1, AVFormatParameters *ap)
{
struct video_data *s = s1->priv_data;
struct v4l2_input input;
struct v4l2_standard standard;
struct v4l2_streamparm streamparm = { 0 };
struct v4l2_fract *tpf = &streamparm.parm.capture.timeperframe;
int i;
streamparm.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
if (ap->channel>=0) {
/* set tv video input */
memset (&input, 0, sizeof (input));
input.index = ap->channel;
if (ioctl(s->fd, VIDIOC_ENUMINPUT, &input) < 0) {
av_log(s1, AV_LOG_ERROR, "The V4L2 driver ioctl enum input failed:\n");
return AVERROR(EIO);
}
av_log(s1, AV_LOG_DEBUG, "The V4L2 driver set input_id: %d, input: %s\n",
ap->channel, input.name);
if (ioctl(s->fd, VIDIOC_S_INPUT, &input.index) < 0) {
av_log(s1, AV_LOG_ERROR, "The V4L2 driver ioctl set input(%d) failed\n",
ap->channel);
return AVERROR(EIO);
}
}
if (ap->standard) {
av_log(s1, AV_LOG_DEBUG, "The V4L2 driver set standard: %s\n",
ap->standard);
/* set tv standard */
memset (&standard, 0, sizeof (standard));
for(i=0;;i++) {
standard.index = i;
if (ioctl(s->fd, VIDIOC_ENUMSTD, &standard) < 0) {
av_log(s1, AV_LOG_ERROR, "The V4L2 driver ioctl set standard(%s) failed\n",
ap->standard);
return AVERROR(EIO);
}
if (!strcasecmp(standard.name, ap->standard)) {
break;
}
}
av_log(s1, AV_LOG_DEBUG, "The V4L2 driver set standard: %s, id: %"PRIu64"\n",
ap->standard, (uint64_t)standard.id);
if (ioctl(s->fd, VIDIOC_S_STD, &standard.id) < 0) {
av_log(s1, AV_LOG_ERROR, "The V4L2 driver ioctl set standard(%s) failed\n",
ap->standard);
return AVERROR(EIO);
}
}
if (ap->time_base.num && ap->time_base.den) {
av_log(s1, AV_LOG_DEBUG, "Setting time per frame to %d/%d\n",
ap->time_base.num, ap->time_base.den);
tpf->numerator = ap->time_base.num;
tpf->denominator = ap->time_base.den;
if (ioctl(s->fd, VIDIOC_S_PARM, &streamparm) != 0) {
av_log(s1, AV_LOG_ERROR,
"ioctl set time per frame(%d/%d) failed\n",
ap->time_base.num, ap->time_base.den);
return AVERROR(EIO);
}
if (ap->time_base.den != tpf->denominator ||
ap->time_base.num != tpf->numerator) {
av_log(s1, AV_LOG_INFO,
"The driver changed the time per frame from %d/%d to %d/%d\n",
ap->time_base.num, ap->time_base.den,
tpf->numerator, tpf->denominator);
}
} else {
/* if timebase value is not set in ap, read the timebase value from the driver */
if (ioctl(s->fd, VIDIOC_G_PARM, &streamparm) != 0) {
av_log(s1, AV_LOG_ERROR, "ioctl(VIDIOC_G_PARM): %s\n", strerror(errno));
return AVERROR(errno);
}
}
ap->time_base.num = tpf->numerator;
ap->time_base.den = tpf->denominator;
return 0;
}
static uint32_t device_try_init(AVFormatContext *s1,
const AVFormatParameters *ap,
int *width,
int *height,
enum CodecID *codec_id)
{
uint32_t desired_format = fmt_ff2v4l(ap->pix_fmt, s1->video_codec_id);
if (desired_format == 0 ||
device_init(s1, width, height, desired_format) < 0) {
int i;
desired_format = 0;
for (i = 0; i<FF_ARRAY_ELEMS(fmt_conversion_table); i++) {
if (s1->video_codec_id == CODEC_ID_NONE ||
fmt_conversion_table[i].codec_id == s1->video_codec_id) {
desired_format = fmt_conversion_table[i].v4l2_fmt;
if (device_init(s1, width, height, desired_format) >= 0) {
break;
}
desired_format = 0;
}
}
}
if (desired_format != 0) {
*codec_id = fmt_v4l2codec(desired_format);
assert(*codec_id != CODEC_ID_NONE);
}
return desired_format;
}
static int v4l2_read_header(AVFormatContext *s1, AVFormatParameters *ap)
{
struct video_data *s = s1->priv_data;
AVStream *st;
int res;
uint32_t desired_format, capabilities;
enum CodecID codec_id;
st = av_new_stream(s1, 0);
if (!st) {
return AVERROR(ENOMEM);
}
av_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
s->width = ap->width;
s->height = ap->height;
capabilities = 0;
s->fd = device_open(s1, &capabilities);
if (s->fd < 0) {
return AVERROR(EIO);
}
av_log(s1, AV_LOG_VERBOSE, "[%d]Capabilities: %x\n", s->fd, capabilities);
if (!s->width && !s->height) {
struct v4l2_format fmt;
av_log(s1, AV_LOG_VERBOSE, "Querying the device for the current frame size\n");
fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
if (ioctl(s->fd, VIDIOC_G_FMT, &fmt) < 0) {
av_log(s1, AV_LOG_ERROR, "ioctl(VIDIOC_G_FMT): %s\n", strerror(errno));
return AVERROR(errno);
}
s->width = fmt.fmt.pix.width;
s->height = fmt.fmt.pix.height;
av_log(s1, AV_LOG_VERBOSE, "Setting frame size to %dx%d\n", s->width, s->height);
}
desired_format = device_try_init(s1, ap, &s->width, &s->height, &codec_id);
if (desired_format == 0) {
av_log(s1, AV_LOG_ERROR, "Cannot find a proper format for "
"codec_id %d, pix_fmt %d.\n", s1->video_codec_id, ap->pix_fmt);
close(s->fd);
return AVERROR(EIO);
}
if (av_image_check_size(s->width, s->height, 0, s1) < 0)
return AVERROR(EINVAL);
s->frame_format = desired_format;
if (v4l2_set_parameters(s1, ap) < 0)
return AVERROR(EIO);
st->codec->pix_fmt = fmt_v4l2ff(desired_format, codec_id);
s->frame_size = avpicture_get_size(st->codec->pix_fmt, s->width, s->height);
if (capabilities & V4L2_CAP_STREAMING) {
s->io_method = io_mmap;
res = mmap_init(s1);
if (res == 0) {
res = mmap_start(s1);
}
} else {
s->io_method = io_read;
res = read_init(s1);
}
if (res < 0) {
close(s->fd);
return AVERROR(EIO);
}
s->top_field_first = first_field(s->fd);
st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
st->codec->codec_id = codec_id;
st->codec->width = s->width;
st->codec->height = s->height;
st->codec->time_base.den = ap->time_base.den;
st->codec->time_base.num = ap->time_base.num;
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 (s->io_method == io_mmap) {
av_init_packet(pkt);
res = mmap_read_frame(s1, pkt);
} else if (s->io_method == io_read) {
if (av_new_packet(pkt, s->frame_size) < 0)
return AVERROR(EIO);
res = read_frame(s1, pkt);
} else {
return AVERROR(EIO);
}
if (res < 0) {
return res;
}
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 pkt->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 ff_v4l2_demuxer = {
"video4linux2",
NULL_IF_CONFIG_SMALL("Video4Linux2 device grab"),
sizeof(struct video_data),
NULL,
v4l2_read_header,
v4l2_read_packet,
v4l2_read_close,
.flags = AVFMT_NOFILE,
};
Reference in New Issue View Git Blame Copy Permalink