L_BM_HISTOEQ

Send this message to histogram-equalize an L_BITMAPCLASS window's bitmap.

Parameter	Meaning
wParam	Specifies whether the window should be redrawn to reflect the image changes. Use 1 to redraw the window, or 0 not to redraw it.
lParam	Reserved. Set to NULL.

Returns

SUCCESS	Function was successful.
< 0	An error occurred. Refer to Return Codes.