capOverlay macro (vfw.h)

Article
02/22/2024

The capOverlay macro enables or disables overlay mode. In overlay mode, video is displayed using hardware overlay. You can use this macro or explicitly call the WM_CAP_SET_OVERLAY message.

Syntax

void capOverlay(
   hwnd,
   f
);

Parameters

hwnd

Handle to a capture window.

f

Overlay flag. Specify TRUE for this parameter to enable overlay mode or FALSE to disable it.

Return value

None

Remarks

Using an overlay does not require CPU resources.

The fHasOverlay member of the CAPDRIVERCAPS structure indicates whether the device is capable of overlay. The fOverlayWindow member of the CAPSTATUS structure indicates whether overlay mode is currently enabled.

Enabling overlay mode automatically disables preview mode.

Requirements

Requirement	Value
Minimum supported client	Windows 2000 Professional [desktop apps only]
Minimum supported server	Windows 2000 Server [desktop apps only]
Target Platform	Windows
Header	vfw.h