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LEADCAPTUREOPTION

Summary

This structure is used in LScreenCapture::SetCaptureOptions and LScreenCapture::GetCaptureOptions to set/get the capture options.

Syntax

typedef struct tagLEADCAPTUREOPTION 
{ 
   L_UINT uStructSize; 
   HCURSOR hCursor; 
   HCURSOR hStatusCursor; 
   L_INT nHotKey; 
   L_UINT uHotKeyModifiers; 
   L_INT nCancelKey; 
   L_INT nDelay; 
   L_UINT uCount; 
   L_INT nInterval; 
   L_UINT32 uFlags; 
} LEADCAPTUREOPTION, * pLEADCAPTUREOPTION;

Members

uStructSize

Size of this structure. Use sizeof (LAYERINFO).

hCursor

Cursor to place on image after capture. Default is NULL.

hStatusCursor

Cursor to display as status between multiple captures. Default is NULL.

nHotKey

Key code for activation key. Default is F11.

The user can immediately capture by setting the hot key to zero (0).

uHotKeyModifiers

Modifier keys used with nHotKey. Possible values are listed below and may be combined. Default is 0.

Value	Meaning
MOD_ALT	Alt Key pressed.
MOD_CONTROL	Control key pressed.
MOD_SHIFT	Shift key pressed.
0	No modifier key was pressed.

nCancelKey

Key code for capture operation cancel key. Default is ESC. You cannot set this to the 'ALT' key (VK_MENU). If you do, it will be ignored internally and set to 'ESC' (VK_ESCAPE).

nDelay

Milliseconds delay before capture. Default is 0.

uCount

Number of times to capture. 0 or 1 means one capture, 2 means 2 captures, etc. Default is 1.

nInterval

Milliseconds delay between captures. Default is 0.

uFlags

Flag that indicates whether to optimize hotkey processing. Possible values are:

Value	Meaning
0	[0x0000] Perform normal hot key processing.
CAPTURE_OPTIMIZED_HOTKEY	[0x0001] Use a global system hook for hotkey processing.

Comments

Normally, when a capture function is called, the function enters a loop, and waits for the hot key specified in nHotKey to be pressed, before capturing. This loop can cause the CPU usage indicator to appear maxed out. Specifying CAPTURE_OPTIMIZED_HOTKEY in uFlags will cause the capture function to return immediately, if a hotkey has been specified in nHotKey. In this case, a global system hotkey hook is established and used to wait for the hotkey to be pressed. When the hotkey is pressed, the capture is performed and the callback passed to the capture function is called with the result of the capture. Use this option only if the normal behavior is causing your application problems. This option is ignored in Win95/98/Me.

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