| The PIXCI® SV4 imaging board can, in conjunction
with an appropriate S/VGA card, display live video directly
upon the VGA monitor, under Win 95/98 or Win NT. This allows
full video rate display, even on slower PC's; and avoids using
processor power to repeatedly copy images from system memory
to the S/VGA.
With selected S/VGA cards, graphic overlays over live video
are also available!
The S/VGA requirements are:
- S/VGA drivers supporting DirectDraw.
- Hardware overlay feature.
- Overlay surface accepting UYVY or YUYV format video.
- Hardware cursor/sprite/icon support.
- Hardware chroma key support (optional, for graphic overlays
on live video).
In addition, the DirectX enhancement must be installed in
Win 95 (DirectX is included with Win NT and need not be installed
separately). DirectX is available from Microsoft and most
VGA manufacturer's web sites, for example:
The live video feature expects a color video format. If
using a monochrome camera, simply select NTSC (or PAL) format;
the video format will be color, but the perceived image will
remain monochrome.
For users of "C" libraries, putting live video
into a window requires only two, simple, function calls. Thereafter,
any of the Windows standard Graphics Device Interface
functions (e.g. TextOut, LineTo, or their MFC or Visual Basic
equivalents) can be used to draw graphics or text in the window,
which automatically appears overlayed on the live video!
|
|
S/VGA cards performance tested with the PIXCI® SV4
Imaging Board:
ATI with 3D Rage Pro Chip. Provides chroma
keying support, and thus graphics over live video. Displays
full resolution RS-170. Supports Win NT.
ATI with 3D Rage II Chip. Provides chroma keying
support, and thus graphics over live video. Resolution
of live video limited to 720x540.
Hercules Dynamite 128/Video. Doesn't support
graphics on top of live video. With 4 Megabytes of VGA
memory, can display full resolution RS-170. As last
checked, doesn't support live video under Win NT.
Note. Any Win 95/98 or Win NT compatible S/VGA
card may be used for almost-live video, with the liveliness
depending upon the image size and CPU speed.
S/VGA card models and features change often; the S/VGA
card manufacturer can advise whether currently sold
cards maintain the necessary features.
|
|