Image Capture and Storage:

Step 1 

In the prototypes, video images that supplement each resource
record were digitized (frame grabbed) and stored in the graphics
database using an image capture board.  The images were captured
from videotape (VCR) and directly from video camera.  Because of
the higher resolution and sharper image quality inherent in
bypassing the intermediary [1/2"] VCR environment, the video
camera was used to capture images directly from historical
photographs, slides, and drawings.  

Example:  From the CRISTAL worksheet environment, the system
operator presses the [/ G I C] key sequence to select the video
camera as the signal source.  When this command is activated, a
live video image can be displayed on the graphics screen.  The
image is "Frame grabbed" (digitized) by pressing the left mouse
button.  This freezes the selected image on the graphics screen
in a digital format.  The image can then be saved to disk as a
[.TGA] or a [.PIC] file.  Each digitized image must be assigned a
unique filename, with a maximum of eight characters possible for
the filename.  The current default extension, [.TGA] or [.PIC],
will be automatically appended to the filename assignment. 
Unless specified, images will be written to the default image
directory as specified in the Environment menu of the CRISTAL
program (press [/ E D I] from the worksheet to display the
Environment settings).  Images not saved after digitizing will be
overwritten (replaced) by the next digitized image.  After the
first image is digitized, the user can return to live video by
pressing and holding the left mouse button.  Releasing the button
digitizes another image.  Pressing the right mouse button
terminates the "Frame grab" procedure.

<gfile01> Index to the Appendices
<gfile18> Application Development
<gfile20> Image Capture and Storage 2.