This demo will show an animated image like an old TV without signal on your desktop, under your windows and icons. It does this by using DirectDraw overlay surfaces that are masked to the desktop background color. DirectX 7 or later is needed to run the demo.
Neil Younusov from Russia found a typo in the code. In the function CopyImageToSurface() Y0 is computed using the factors 0.29, 0.59, and 0.14, this should be 0.29, 0.57, and 0.14 (sum 1.0) just like for Y1.