v4l2src

v4l2src — Reads frames from a Video4Linux2 device

Synopsis

struct              GstV4l2Src;

Object Hierarchy

  GObject
   +----GInitiallyUnowned
         +----GstObject
               +----GstElement
                     +----GstBaseSrc
                           +----GstPushSrc
                                 +----GstV4l2Src

Implemented Interfaces

GstV4l2Src implements GstURIHandler, GstTuner, GstColorBalance and GstVideoOrientation.

Properties

  "device"                   gchar*                : Read / Write
  "device-name"              gchar*                : Read
  "flags"                    GstV4l2DeviceTypeFlags  : Read
  "queue-size"               guint                 : Read / Write
  "always-copy"              gboolean              : Read / Write
  "device-fd"                gint                  : Read
  "brightness"               gint                  : Read / Write
  "contrast"                 gint                  : Read / Write
  "decimate"                 gint                  : Read / Write
  "hue"                      gint                  : Read / Write
  "saturation"               gint                  : Read / Write
  "norm"                     V4L2_TV_norms         : Read / Write
  "io-mode"                  GstV4l2IOMode         : Read / Write
  "extra-controls"           GstStructure*         : Read / Write
  "force-aspect-ratio"       gboolean              : Read / Write
  "pixel-aspect-ratio"       gchar*                : Read / Write

Signals

  "prepare-format"                                 : Run Last

Description

Synopsis

Element Information

plugin

video4linux2

author

Edgard Lima <edgard.lima@indt.org.br>, Stefan Kost <ensonic@users.sf.net>

class

Source/Video

Element Pads

name

src

direction

source

presence

always

details

video/x-raw, format=(string)RGB15, width=(int)[ 1, 32768 ], height=(int)[ 1, 32768 ], framerate=(fraction)[ 0/1, 100/1 ]

video/x-raw, format=(string)RGB16, width=(int)[ 1, 32768 ], height=(int)[ 1, 32768 ], framerate=(fraction)[ 0/1, 100/1 ]

video/x-raw, format=(string)BGR, width=(int)[ 1, 32768 ], height=(int)[ 1, 32768 ], framerate=(fraction)[ 0/1, 100/1 ]

video/x-raw, format=(string)RGB, width=(int)[ 1, 32768 ], height=(int)[ 1, 32768 ], framerate=(fraction)[ 0/1, 100/1 ]

video/x-raw, format=(string)BGRx, width=(int)[ 1, 32768 ], height=(int)[ 1, 32768 ], framerate=(fraction)[ 0/1, 100/1 ]

video/x-raw, format=(string)RGBx, width=(int)[ 1, 32768 ], height=(int)[ 1, 32768 ], framerate=(fraction)[ 0/1, 100/1 ]

video/x-raw, format=(string)GRAY8, width=(int)[ 1, 32768 ], height=(int)[ 1, 32768 ], framerate=(fraction)[ 0/1, 100/1 ]

video/x-raw, format=(string)YVU9, width=(int)[ 1, 32768 ], height=(int)[ 1, 32768 ], framerate=(fraction)[ 0/1, 100/1 ]

video/x-raw, format=(string)YV12, width=(int)[ 1, 32768 ], height=(int)[ 1, 32768 ], framerate=(fraction)[ 0/1, 100/1 ]

video/x-raw, format=(string)YUY2, width=(int)[ 1, 32768 ], height=(int)[ 1, 32768 ], framerate=(fraction)[ 0/1, 100/1 ]

video/x-raw, format=(string)UYVY, width=(int)[ 1, 32768 ], height=(int)[ 1, 32768 ], framerate=(fraction)[ 0/1, 100/1 ]

video/x-raw, format=(string)Y42B, width=(int)[ 1, 32768 ], height=(int)[ 1, 32768 ], framerate=(fraction)[ 0/1, 100/1 ]

video/x-raw, format=(string)Y41B, width=(int)[ 1, 32768 ], height=(int)[ 1, 32768 ], framerate=(fraction)[ 0/1, 100/1 ]

video/x-raw, format=(string)NV12, width=(int)[ 1, 32768 ], height=(int)[ 1, 32768 ], framerate=(fraction)[ 0/1, 100/1 ]

video/x-raw, format=(string)NV21, width=(int)[ 1, 32768 ], height=(int)[ 1, 32768 ], framerate=(fraction)[ 0/1, 100/1 ]

video/x-raw, format=(string)YUV9, width=(int)[ 1, 32768 ], height=(int)[ 1, 32768 ], framerate=(fraction)[ 0/1, 100/1 ]

video/x-raw, format=(string)I420, width=(int)[ 1, 32768 ], height=(int)[ 1, 32768 ], framerate=(fraction)[ 0/1, 100/1 ]

video/x-bayer, width=(int)[ 1, 32768 ], height=(int)[ 1, 32768 ], framerate=(fraction)[ 0/1, 100/1 ]

image/jpeg, width=(int)[ 1, 32768 ], height=(int)[ 1, 32768 ], framerate=(fraction)[ 0/1, 100/1 ]

image/jpeg, width=(int)[ 1, 32768 ], height=(int)[ 1, 32768 ], framerate=(fraction)[ 0/1, 100/1 ]

image/jpeg, width=(int)[ 1, 32768 ], height=(int)[ 1, 32768 ], framerate=(fraction)[ 0/1, 100/1 ]

video/x-dv, systemstream=(boolean)true, width=(int)[ 1, 32768 ], height=(int)[ 1, 32768 ], framerate=(fraction)[ 0/1, 100/1 ]

video/mpegts

video/mpeg, mpegversion=(int)4, systemstream=(boolean)false, width=(int)[ 1, 32768 ], height=(int)[ 1, 32768 ], framerate=(fraction)[ 0/1, 100/1 ]

video/x-h263, variant=(string)itu, width=(int)[ 1, 32768 ], height=(int)[ 1, 32768 ], framerate=(fraction)[ 0/1, 100/1 ]

video/x-h264, width=(int)[ 1, 32768 ], height=(int)[ 1, 32768 ], framerate=(fraction)[ 0/1, 100/1 ]

video/x-sonix, width=(int)[ 1, 32768 ], height=(int)[ 1, 32768 ], framerate=(fraction)[ 0/1, 100/1 ]

video/x-pwc1, width=(int)[ 1, 32768 ], height=(int)[ 1, 32768 ], framerate=(fraction)[ 0/1, 100/1 ]

video/x-pwc2, width=(int)[ 1, 32768 ], height=(int)[ 1, 32768 ], framerate=(fraction)[ 0/1, 100/1 ]

video/x-raw, format=(string)YVYU, width=(int)[ 1, 32768 ], height=(int)[ 1, 32768 ], framerate=(fraction)[ 0/1, 100/1 ]

Details

struct GstV4l2Src

struct GstV4l2Src;

Property Details

The "device" property

  "device"                   gchar*                : Read / Write

Device location.

Default value: "/dev/video0"


The "device-name" property

  "device-name"              gchar*                : Read

Name of the device.

Default value: NULL


The "flags" property

  "flags"                    GstV4l2DeviceTypeFlags  : Read

Device type flags.


The "queue-size" property

  "queue-size"               guint                 : Read / Write

Number of buffers to be enqueud in the driver in streaming mode.

Allowed values: [1,16]

Default value: 2


The "always-copy" property

  "always-copy"              gboolean              : Read / Write

If the buffer will or not be used directly from mmap.

Default value: TRUE


The "device-fd" property

  "device-fd"                gint                  : Read

File descriptor of the device.

Allowed values: >= G_MAXULONG

Default value: -1


The "brightness" property

  "brightness"               gint                  : Read / Write

Picture brightness, or more precisely, the black level.

Default value: 0


The "contrast" property

  "contrast"                 gint                  : Read / Write

Picture contrast or luma gain.

Default value: 0


The "decimate" property

  "decimate"                 gint                  : Read / Write

Only use every nth frame.

Allowed values: >= 1

Default value: 1


The "hue" property

  "hue"                      gint                  : Read / Write

Hue or color balance.

Default value: 0


The "saturation" property

  "saturation"               gint                  : Read / Write

Picture color saturation or chroma gain.

Default value: 0


The "norm" property

  "norm"                     V4L2_TV_norms         : Read / Write

video standard.

Default value: none


The "io-mode" property

  "io-mode"                  GstV4l2IOMode         : Read / Write

I/O mode.

Default value: GST_V4L2_IO_AUTO


The "extra-controls" property

  "extra-controls"           GstStructure*         : Read / Write

Extra v4l2 controls (CIDs) for the device.


The "force-aspect-ratio" property

  "force-aspect-ratio"       gboolean              : Read / Write

When enabled, the pixel aspect ratio will be enforced.

Default value: TRUE


The "pixel-aspect-ratio" property

  "pixel-aspect-ratio"       gchar*                : Read / Write

Overwrite the pixel aspect ratio of the device.

Default value: "1/1"

Signal Details

The "prepare-format" signal

void                user_function                      (GstV4l2Src *gstv4l2src,
                                                        gint        arg1,
                                                        GstCaps    *arg2,
                                                        gpointer    user_data)       : Run Last

gstv4l2src :

the object which received the signal.

user_data :

user data set when the signal handler was connected.