labview计算不规则形面积

labview2013版本视觉开发包可打开该例程，可以求取计算指定图像区域中指定灰度范围的像素面积。

我们将labview面板中指定颜色透明，剩下的图形就构成了不规则labview界面，我们要用到如下三个函数：

1.Retrieves information about the specified window.

2.Changes an attribute of the specified window. The function also sets the 32-bit (long) value at the specified offset into the extra window memory.

3.Sets the opacity and transparency color key of a layered window.