libavdevice/v4l2.c File Reference

Video4Linux2 grab interface. More...

#include "config.h"
#include "libavformat/internal.h"
#include <unistd.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <sys/time.h>
#include <linux/videodev2.h>
#include <time.h>
#include "libavutil/imgutils.h"
#include "libavutil/log.h"
#include "libavutil/opt.h"
#include "avdevice.h"
#include "libavutil/parseutils.h"
#include "libavutil/pixdesc.h"
#include "libavutil/avstring.h"

Go to the source code of this file.

Data Structures

struct video_data

struct buff_data

struct fmt_map

Defines

#define v4l2_open   open

#define v4l2_close   close

#define v4l2_dup   dup

#define v4l2_ioctl   ioctl

#define v4l2_read   read

#define v4l2_mmap   mmap

#define v4l2_munmap   munmap

#define V4L_ALLFORMATS   3

#define V4L_RAWFORMATS   1

#define V4L_COMPFORMATS   2

#define OFFSET(x)   offsetof(struct video_data, x)

#define DEC   AV_OPT_FLAG_DECODING_PARAM

Functions

static int device_open (AVFormatContext *ctx)

static int device_init (AVFormatContext *ctx, int *width, int *height, uint32_t pix_fmt)

static int first_field (int fd)

static uint32_t fmt_ff2v4l (enum PixelFormat pix_fmt, enum CodecID codec_id)

static enum PixelFormat fmt_v4l2ff (uint32_t v4l2_fmt, enum CodecID codec_id)

static enum CodecID fmt_v4l2codec (uint32_t v4l2_fmt)

static void list_formats (AVFormatContext *ctx, int fd, int type)

static int mmap_init (AVFormatContext *ctx)

static void mmap_release_buffer (AVPacket *pkt)

static int mmap_read_frame (AVFormatContext *ctx, AVPacket *pkt)

static int mmap_start (AVFormatContext *ctx)

static void mmap_close (struct video_data *s)

static int v4l2_set_parameters (AVFormatContext *s1, AVFormatParameters *ap)

static uint32_t device_try_init (AVFormatContext *s1, enum PixelFormat pix_fmt, int *width, int *height, enum CodecID *codec_id)

static int v4l2_read_header (AVFormatContext *s1, AVFormatParameters *ap)

static int v4l2_read_packet (AVFormatContext *s1, AVPacket *pkt)

static int v4l2_read_close (AVFormatContext *s1)

Variables

static const int desired_video_buffers = 256

static struct fmt_map fmt_conversion_table []

static const AVOption options []

static const AVClass v4l2_class

AVInputFormat ff_v4l2_demuxer

Detailed Description

Video4Linux2 grab interface.

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_*

Definition in file v4l2.c.

Define Documentation

#define DEC AV_OPT_FLAG_DECODING_PARAM

Definition at line 831 of file v4l2.c.

#define OFFSET ( x ) offsetof(struct video_data, x)

Definition at line 830 of file v4l2.c.

#define v4l2_close close

Definition at line 62 of file v4l2.c.

Referenced by device_open(), v4l2_read_close(), and v4l2_read_header().

#define v4l2_dup dup

Definition at line 63 of file v4l2.c.

#define v4l2_ioctl ioctl

Definition at line 64 of file v4l2.c.

Referenced by device_init(), device_open(), first_field(), mmap_close(), mmap_init(), mmap_read_frame(), mmap_release_buffer(), mmap_start(), v4l2_read_header(), and v4l2_set_parameters().

#define v4l2_mmap mmap

Definition at line 66 of file v4l2.c.

Referenced by mmap_init().

#define v4l2_munmap munmap

Definition at line 67 of file v4l2.c.

Referenced by mmap_close().

#define v4l2_open open

Definition at line 61 of file v4l2.c.

Referenced by device_open().

#define v4l2_read read

Definition at line 65 of file v4l2.c.

#define V4L_ALLFORMATS 3

Definition at line 72 of file v4l2.c.

#define V4L_COMPFORMATS 2

Definition at line 74 of file v4l2.c.

Referenced by list_formats().

#define V4L_RAWFORMATS 1

Definition at line 73 of file v4l2.c.

Referenced by list_formats().

Function Documentation

static int device_init	(	AVFormatContext *	ctx,
		int *	width,
		int *	height,
		uint32_t	pix_fmt
	)			`[static]`

Definition at line 195 of file v4l2.c.

Referenced by device_try_init().

static int device_open ( AVFormatContext * ctx ) [static]

Definition at line 127 of file v4l2.c.

Referenced by v4l2_read_header().

static uint32_t device_try_init	(	AVFormatContext *	s1,
		enum PixelFormat	pix_fmt,
		int *	width,
		int *	height,
		enum CodecID *	codec_id
	)			`[static]`

Definition at line 653 of file v4l2.c.

Referenced by v4l2_read_header().

static int first_field ( int fd ) [static]

Definition at line 236 of file v4l2.c.

Referenced by dnxhd_decode_frame(), dnxhd_encode_picture(), and v4l2_read_header().

static uint32_t fmt_ff2v4l	(	enum PixelFormat	pix_fmt,
		enum CodecID	codec_id
	)			`[static]`

Definition at line 252 of file v4l2.c.

Referenced by device_try_init().

static enum CodecID fmt_v4l2codec ( uint32_t v4l2_fmt ) [static]

Definition at line 282 of file v4l2.c.

Referenced by device_try_init(), and list_formats().

static enum PixelFormat fmt_v4l2ff	(	uint32_t	v4l2_fmt,
		enum CodecID	codec_id
	)			`[static]`

Definition at line 268 of file v4l2.c.

Referenced by list_formats(), and v4l2_read_header().

static void list_formats	(	AVFormatContext *	ctx,
		int	fd,
		int	type
	)			`[static]`

Definition at line 321 of file v4l2.c.

Referenced by v4l2_read_header().

static void mmap_close ( struct video_data * s ) [static]

Definition at line 541 of file v4l2.c.

Referenced by v4l2_read_close().

static int mmap_init ( AVFormatContext * ctx ) [static]

Definition at line 360 of file v4l2.c.

Referenced by v4l2_read_header().

static int mmap_read_frame	(	AVFormatContext *	ctx,
		AVPacket *	pkt
	)			`[static]`

Definition at line 454 of file v4l2.c.

Referenced by v4l2_read_packet().

static void mmap_release_buffer ( AVPacket * pkt ) [static]

Definition at line 430 of file v4l2.c.

Referenced by mmap_read_frame().

static int mmap_start ( AVFormatContext * ctx ) [static]

Definition at line 507 of file v4l2.c.

Referenced by v4l2_read_header().

static int v4l2_read_close ( AVFormatContext * s1 ) [static]

Definition at line 820 of file v4l2.c.

static int v4l2_read_header	(	AVFormatContext *	s1,
		AVFormatParameters *	ap
	)			`[static]`

Definition at line 686 of file v4l2.c.

static int v4l2_read_packet	(	AVFormatContext *	s1,
		AVPacket *	pkt
	)			`[static]`

Definition at line 801 of file v4l2.c.

static int v4l2_set_parameters	(	AVFormatContext *	s1,
		AVFormatParameters *	ap
	)			`[static]`

Definition at line 558 of file v4l2.c.

Referenced by v4l2_read_header().

Variable Documentation

const int desired_video_buffers = 256 [static]

Definition at line 70 of file v4l2.c.

Referenced by mmap_init().

AVInputFormat ff_v4l2_demuxer

Initial value:

 {
    .name           = "video4linux2,v4l2",
    .long_name      = NULL_IF_CONFIG_SMALL("Video4Linux2 device grab"),
    .priv_data_size = sizeof(struct video_data),
    .read_header    = v4l2_read_header,
    .read_packet    = v4l2_read_packet,
    .read_close     = v4l2_read_close,
    .flags          = AVFMT_NOFILE,
    .priv_class     = &v4l2_class,
}

Definition at line 854 of file v4l2.c.

struct fmt_map fmt_conversion_table[] [static]

Initial value:

 {
    
    { 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    },
}

Definition at line 108 of file v4l2.c.

const AVOption options[] [static]

Initial value:

 {
    { "standard",     "TV standard, used only by analog frame grabber",            OFFSET(standard),     AV_OPT_TYPE_STRING, {.str = NULL }, 0, 0,       DEC },
    { "channel",      "TV channel, used only by frame grabber",                    OFFSET(channel),      AV_OPT_TYPE_INT,    {.dbl = 0 },    0, INT_MAX, DEC },
    { "video_size",   "A string describing frame size, such as 640x480 or hd720.", OFFSET(video_size),   AV_OPT_TYPE_STRING, {.str = NULL},  0, 0,       DEC },
    { "pixel_format", "Preferred pixel format",                                    OFFSET(pixel_format), AV_OPT_TYPE_STRING, {.str = NULL},  0, 0,       DEC },
    { "input_format", "Preferred pixel format (for raw video) or codec name",      OFFSET(pixel_format), AV_OPT_TYPE_STRING, {.str = NULL},  0, 0,       DEC },
    { "framerate",    "",                                                          OFFSET(framerate),    AV_OPT_TYPE_STRING, {.str = NULL},  0, 0,       DEC },
    { "list_formats", "List available formats and exit",                           OFFSET(list_format),  AV_OPT_TYPE_INT,    {.dbl = 0 },  0, INT_MAX, DEC, "list_formats" },
    { "all",          "Show all available formats",                                OFFSET(list_format),  AV_OPT_TYPE_CONST,  {.dbl = V4L_ALLFORMATS  },    0, INT_MAX, DEC, "list_formats" },
    { "raw",          "Show only non-compressed formats",                          OFFSET(list_format),  AV_OPT_TYPE_CONST,  {.dbl = V4L_RAWFORMATS  },    0, INT_MAX, DEC, "list_formats" },
    { "compressed",   "Show only compressed formats",                              OFFSET(list_format),  AV_OPT_TYPE_CONST,  {.dbl = V4L_COMPFORMATS },    0, INT_MAX, DEC, "list_formats" },
    { NULL },
}

Definition at line 833 of file v4l2.c.

const AVClass v4l2_class [static]

Initial value:

 {
    .class_name = "V4L2 indev",
    .item_name  = av_default_item_name,
    .option     = options,
    .version    = LIBAVUTIL_VERSION_INT,
}

Definition at line 847 of file v4l2.c.


Data Structures
struct	video_data
struct	buff_data
struct	fmt_map
Defines
#define	v4l2_open open
#define	v4l2_close close
#define	v4l2_dup dup
#define	v4l2_ioctl ioctl
#define	v4l2_read read
#define	v4l2_mmap mmap
#define	v4l2_munmap munmap
#define	V4L_ALLFORMATS 3
#define	V4L_RAWFORMATS 1
#define	V4L_COMPFORMATS 2
#define	OFFSET(x) offsetof(struct video_data, x)
#define	DEC AV_OPT_FLAG_DECODING_PARAM
Functions
static int	device_open (AVFormatContext *ctx)
static int	device_init (AVFormatContext ctx, int width, int *height, uint32_t pix_fmt)
static int	first_field (int fd)
static uint32_t	fmt_ff2v4l (enum PixelFormat pix_fmt, enum CodecID codec_id)
static enum PixelFormat	fmt_v4l2ff (uint32_t v4l2_fmt, enum CodecID codec_id)
static enum CodecID	fmt_v4l2codec (uint32_t v4l2_fmt)
static void	list_formats (AVFormatContext *ctx, int fd, int type)
static int	mmap_init (AVFormatContext *ctx)
static void	mmap_release_buffer (AVPacket *pkt)
static int	mmap_read_frame (AVFormatContext ctx, AVPacket pkt)
static int	mmap_start (AVFormatContext *ctx)
static void	mmap_close (struct video_data *s)
static int	v4l2_set_parameters (AVFormatContext s1, AVFormatParameters ap)
static uint32_t	device_try_init (AVFormatContext s1, enum PixelFormat pix_fmt, int width, int height, enum CodecID codec_id)
static int	v4l2_read_header (AVFormatContext s1, AVFormatParameters ap)
static int	v4l2_read_packet (AVFormatContext s1, AVPacket pkt)
static int	v4l2_read_close (AVFormatContext *s1)
Variables
static const int	desired_video_buffers = 256
static struct fmt_map	fmt_conversion_table []
static const AVOption	options []
static const AVClass	v4l2_class
AVInputFormat	ff_v4l2_demuxer