Question

vc++图像处理如何提取像素值

Answer 1

要想捕获当前线程内（也就是当前CxxxApp）所有窗口上光标所在的像素颜色，需要重载CxxxApp的PreTranslateMessage函数，加：
if ( pMSG->message == WM_MOUSEMOVE)
{
CPoint ptScreen;
GetCursorPos(&ptScreen);
CWnd*DeskWnd = GetDesktopWindow();
CDC*DeskDC = DeskWnd->GetDC();
COLORREF clr = DeskDC->GetPixel(ptScreen);
DeskWnd->ReleaseDC(DeskDC);

CString strShow;
strShow.Format("%d", clr);
...
}

要想捕获当前屏幕任何地方的像素值,要先SetCapute,然后在使用上面的代码。

Answer 2

CPoint point;
GetCursorPos(&point);//get cursor pos
HDC hDC = ::GetDC(NULL);//lock paint DC
COLORREF colorref = ::GetPixel(hDC, point.x, point.y); //get the cursor color
GetRValue(colorref);//store red color
GetGValue(colorref);//store green color
GetBValue(colorref);//store blue color
::ReleaseDC(NULL, hDC);//unlock DC

GetPixel是CDC类里的函数