vl_camera(3)vl_camera(3)NAME
vl_camera.h - unified camera controls via the video library
SYNOPSIS
#include <dmedia/vl_camera.h>
-lvl
DESCRIPTION
vl_camera.h header file provides a machine independent interface to basic
video camera controls. These controls can be used via the video library
using the vlGetControl and vlSetControl function calls. Cameras currently
supported are the IndyCam and DVC1.
VL_CAMERA_VENDOR_ID (Vendor ID)
This read-only controls returns the vendor ID string for
the camera. The "SGI Digital Video Camera" string is
prepended to all SGI cameras.
VL_CAMERA_VERSION (Camera Version)
Returns the Camera Version number. For SGI cameras, the
following versions are supported:
VL_CAMERA_VERSION_SGI_INDYCAM (IndyCam),
VL_CAMERA_VERSION_SGI_DVC1 (DVC1),
VL_CAMERA_VERSION_SGI_DVC2 (DVC2)
VL_CAMERA_POWER (Power on/off)
Turns the camera on or off.
VL_CAMERA_RESET (Camera Reset)
Resets the camera. Some delay may be required to affect
this control.
VL_CAMERA_INITIALIZE (Initialize the Camera)
This is different than RESET in that it initializes the
camera registers to some known default values (normally
supplied by the camera manufacturer.)
VL_CAMERA_AUTO_WHITE_BALANCE (White Balance)
The white balance button causes the camera to
automatically configure the red and blue balances to
achieve an overall even toned image. For best results,
hold up a well lit piece of white paper in front of the
camera and click on white balance, the camera will then
calibrate itself.
VL_CAMERA_AUTO_GAIN_CONTROL (AGC Enable)
This toggle button turns on or off the automatic gain
control. When automatic gain control is on, the camera
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continually adjusts itself to changing lighting conditions
in order to produce an even level of brightness. When
automatic gain control is off, it is up to the user or
program to set the proper gain level. If the gain is too
low, then the picture will appear dark; when the gain is
too high it will appear white or washed out.
VL_CAMERA_PIXEL_COUNT (Active Video Width)
Returns the number of pixels per horizontal line.
VL_CAMERA_LINE_COUNT (Active Video Lines)
Returns the number of active lines in a frame.
VL_CAMERA_RATE (Frame Rate)
Returns the frame rate in frames-per-second.
VL_CAMERA_BRIGHTNESS (Brightness)
It is the maximuum value of the low-pass filtered
luminance signal. It is a Read Only value.
VL_CAMERA_EXPOSURE (Exposure)
This adjustment affects the sharpness of the picture.
VL_CAMERA_SHARPNESS (Sharpness)
VL_CAMERA_HUE (Hue)
The hue adjusts the balance between colors in the signal.
VL_CAMERA_RED_BALANCE (Red Balance)
The red balance controls the proportion of red in the
image.
VL_CAMERA_BLUE_BALANCE (Blue Balance)
The blue balance controls the proportion of blue in the
image.
VL_CAMERA_GREEN_BALANCE (Green Balance)
The green balance controls the proportion of green in the
image.
VL_CAMERA_SATURATION (Saturation)
The saturation value affects the overall color intensity
of the image. When saturation is set to zero, the image
will have no color.
VL_CAMERA_RED_SATURATION (Red Saturation)
This affects the intensity(amplitude) of the red color in
the image.
VL_CAMERA_BLUE_SATURATION (Blue Saturation)
This affects the intensity(amplitude) of the blue color in
the image.
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VL_CAMERA_GREEN_SATURATION (Green Saturation)
This affects the intensity(amplitude) of the green color
in the image.
VL_CAMERA_GAMMA (Gamma)
The red, green, and blue channel intensities are specified
as a value between 0 and 255, where 0 is off and 255 is
full intensity for the channel. Due to component
nonlinearities found in most video display monitors, an
intensity value of 200 does not appear twice as bright as
an intensity value of 100. In order to compensate for
these nonlinearities, a lookup table, called a gamma
table, is provided for each channel. The process of
correcting for the monitor nonlinearities is called gamma
correction. The lookup table can be created via equations,
provided by most manufacturers.
VL_CAMERA_GAIN (Gain)
This control is used when the automatic gain has been
turned off. It allows manual adjustment of the camera
exposure. VL_CAMERA_SHUTTER (Shutter Speed) This multiple
choice control lets you control the shutter speed of the
camera. A faster shutter speed lets in less light and may
be used when the amount of light is too high to be
compensated for by the gain control.
VL_CAMERA_ORIENTATION (Image Orientation)
Indicates the order in which the scan lines of the image
are read.
VL_CAMERA_BUTTON,VL_CAMERA_BUTTON_2 (Buttons)
Toggle button controls.
VL_CAMERA_LED,VL_CAMERA_LED_GREEN,
VL_CAMERA_LED_RED,VL_CAMERA_LED_AMBER (led Indicator)
Visual indicators.
VL_CAMERA_ZOOM (Zoom)
VL_CAMERA_PAN (Pan)
VL_CAMERA_TILT (Tilt)
Supported Cameras
This is a list of all basic camera controls. Not all controls are
supported on all platforms and all cameras.
On the Indy, the controls supported are:
VL_CAMERA_AUTO_GAIN_CONTROL
VL_CAMERA_AUTO_WHITE_BALANCE
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VL_CAMERA_SHUTTER
VL_CAMERA_GAIN
VL_CAMERA_BRIGHTNESS (read only)
VL_CAMERA_VERSION (Values supported are:
VL_CAMERA_VERSION_SGI_DVC1,
VL_CAMERA_VERSION_SGI_INDYCAM)
VL_CAMERA_RED_BALANCE
VL_CAMERA_BLUE_BALANCE
VL_CAMERA_SATURATION
VL_CAMERA_GAMMA (if DVC1 attached)
VL_CAMERA_LED (if DVC1 attached)
VL_CAMERA_GREEN_LED (if DVC1 attached)
VL_CAMERA_BUTTON (if DVC1 attached)
On the O2, the controls supported are:
VL_CAMERA_AUTO_GAIN_CONTROL
VL_CAMERA_AUTO_WHITE_BALANCE
VL_CAMERA_SHUTTER
VL_CAMERA_GAIN
VL_CAMERA_BRIGHTNESS (read only)
VL_CAMERA_VERSION (Values supported are:
VL_CAMERA_VERSION_SGI_DVC1)
VL_CAMERA_RED_BALANCE
VL_CAMERA_BLUE_BALANCE
VL_CAMERA_RED_SATURATION
VL_CAMERA_BLUE_SATURATION
VL_CAMERA_GAMMA
VL_CAMERA_RESET
VL_CAMERA_PIXEL_COUNT
VL_CAMERA_LINE_COUNT
VL_CAMERA_LED
VL_CAMERA_GREEN_LED
VL_CAMERA_BUTTON
FILES
/usr/lib/dmedia/vl_camera.h
SEE ALSOvideopanel(1), vino(7), vlinfo(1)
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