Hauppauge WinTV USB - Manual (Page 23)

video frame. When one of these functions are clicked on, the next video frame
is moved into your PC’s main system memory instead of the VGA display. Your
PC’s processor then converts the digitized video image into a 24-bit DIB image
(a format which is used internally in Windows), and then copied back into the
VGA memory so that you can see the image which will be printed or saved. This
becomes a “frozen” image in the window.
The video images which are digitized can be saved to disk, printed to a color or
black/white printer or copied to the clipboard. These functions can be viewed
from the File menu:
There are a few things which need to be noted. First, because a video frame is
composed of two “fields”, an odd field with the odd lines in the image and an
even field composed of the even lines, there might be a distortion in the frozen
image if there was rapid motion while the image was being moved into main
system memory. This distortion is called “interlaced artifact”.
Another item to note is that the video image, when converted into a 24-bit DIB
image, will look lighter than it did when it was in motion. You can adjust the
image’s brightness, contrast and color saturation and hue by clicking on
Configure/Color. These adjustments are made during the digitizing process on
the board and will affect both the “live” image and the frozen image.
Adjusting the video image’s color
You can adjust the brightness, contrast saturation and hue of the live TV image
by using the color adjustment menu. Click on Configure/Color to get the
adjustment menu:
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WinTV-USB
Installation and Reference Manual