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videopanel(1)

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vlinfo(1)



vlcamera(3)                                                      vlcamera(3)



NAME
     vl_camera.h - unified camera controls via the video library

SYNOPSIS
     #include <dmedia/vlcamera.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.



     VLCAMERAVENDORID (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.

     VLCAMERAVERSION   (Camera Version)
                    Returns the Camera Version number. For SGI cameras, the
                    following versions are supported:
                         VLCAMERAVERSIONSGIINDYCAM (IndyCam),
                         VLCAMERAVERSIONSGIDVC1 (DVC1),
                         VLCAMERAVERSIONSGIDVC2 (DVC2)

     VLCAMERAPOWER (Power on/off)
                    Turns the camera on or off.

     VLCAMERARESET (Camera Reset)
                    Resets the camera. Some delay may be required to affect
                    this control.

     VLCAMERAINITIALIZE (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.)

     VLCAMERAAUTOWHITEBALANCE (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.

     VLCAMERAAUTOGAINCONTROL (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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vlcamera(3)                                                      vlcamera(3)



                    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.

     VLCAMERAPIXELCOUNT (Active Video Width)
                    Returns the number of pixels per horizontal line.

     VLCAMERALINECOUNT (Active Video Lines)
                    Returns the number of active lines in a frame.

     VLCAMERARATE (Frame Rate)
                    Returns the frame rate in frames-per-second.

     VLCAMERABRIGHTNESS (Brightness)
                    It is the maximuum value of the low-pass filtered
                    luminance signal. It is a Read Only value.

     VLCAMERAEXPOSURE (Exposure)
                    This adjustment affects the sharpness of the picture.

     VLCAMERASHARPNESS (Sharpness)

     VLCAMERAHUE (Hue)
                    The hue adjusts the balance between colors in the signal.

     VLCAMERAREDBALANCE (Red Balance)
                    The red balance controls the proportion of red in the
                    image.

     VLCAMERABLUEBALANCE (Blue Balance)
                    The blue balance controls the proportion of blue in the
                    image.

     VLCAMERAGREENBALANCE (Green Balance)
                    The green balance controls the proportion of green in the
                    image.

     VLCAMERASATURATION (Saturation)
                    The saturation value affects the overall color intensity
                    of the image.  When saturation is set to zero, the image
                    will have no color.

     VLCAMERAREDSATURATION (Red Saturation)
                    This affects the intensity(amplitude) of the red color in
                    the image.

     VLCAMERABLUESATURATION (Blue Saturation)
                    This affects the intensity(amplitude) of the blue color in
                    the image.



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vlcamera(3)                                                      vlcamera(3)



     VLCAMERAGREENSATURATION (Green Saturation)
                    This affects the intensity(amplitude) of the green color
                    in the image.

     VLCAMERAGAMMA (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.

     VLCAMERAGAIN (Gain)
                    This control is used when the automatic gain has been
                    turned off.  It allows manual adjustment of the camera
                    exposure.  VLCAMERASHUTTER (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.

     VLCAMERAORIENTATION (Image Orientation)
                    Indicates the order in which the scan lines of the image
                    are read.

     VLCAMERABUTTON,VLCAMERABUTTON2 (Buttons)
                    Toggle button controls.

     VLCAMERALED,VLCAMERALEDGREEN,

     VLCAMERALEDRED,VLCAMERALEDAMBER (led Indicator)
                    Visual indicators.

     VLCAMERAZOOM (Zoom)

     VLCAMERAPAN (Pan)

     VLCAMERATILT (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:
          VLCAMERAAUTOGAINCONTROL
          VLCAMERAAUTOWHITEBALANCE



                                                                        Page 3





vlcamera(3)                                                      vlcamera(3)



          VLCAMERASHUTTER
          VLCAMERAGAIN
          VLCAMERABRIGHTNESS (read only)
          VLCAMERAVERSION       (Values supported are:
                                 VLCAMERAVERSIONSGIDVC1,
                                 VLCAMERAVERSIONSGIINDYCAM)
          VLCAMERAREDBALANCE
          VLCAMERABLUEBALANCE
          VLCAMERASATURATION
          VLCAMERAGAMMA         (if DVC1 attached)
          VLCAMERALED           (if DVC1 attached)
          VLCAMERAGREENLED     (if DVC1 attached)
          VLCAMERABUTTON        (if DVC1 attached)

     On the O2, the controls supported are:
          VLCAMERAAUTOGAINCONTROL
          VLCAMERAAUTOWHITEBALANCE
          VLCAMERASHUTTER
          VLCAMERAGAIN
          VLCAMERABRIGHTNESS (read only)
          VLCAMERAVERSION       (Values supported are:
                                 VLCAMERAVERSIONSGIDVC1)
          VLCAMERAREDBALANCE
          VLCAMERABLUEBALANCE
          VLCAMERAREDSATURATION
          VLCAMERABLUESATURATION
          VLCAMERAGAMMA
          VLCAMERARESET
          VLCAMERAPIXELCOUNT
          VLCAMERALINECOUNT
          VLCAMERALED
          VLCAMERAGREENLED
          VLCAMERABUTTON






FILES
     /usr/lib/dmedia/vl_camera.h


SEE ALSO
     videopanel(1), vino(7), vlinfo(1)










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