在加载的.bmp文件上正确使用 BitBlt 来扫描像素

Question

所以我正在开发一个从屏幕进行颜色检测的程序，我有这个函数，可以很好地使用我通过搜索屏幕传递的值查找颜色。

bool findColor(float hue, float sat, float vib, float tol, RECT reg, POINT& loc) {
{
    HWND target = FindWindow(NULL, WINDOWNAME);
    if (!target)
    {
        printf("error, no windown");
    }
    RECT rc;
    GetWindowRect(target, &rc);
    int regLocx, regLocy;
    int x = rc.left + reg.left;
    int y = rc.top + reg.top;
    int w = reg.right - reg.left;
    int h = reg.bottom - reg. top;
    int screen_w = GetSystemMetrics(SM_CXFULLSCREEN);
    int screen_h = GetSystemMetrics(SM_CYFULLSCREEN);
    HDC hdc = GetDC(HWND_DESKTOP);
    HBITMAP hbitmap = CreateCompatibleBitmap(hdc, screen_w, screen_h);
    HDC memdc = CreateCompatibleDC(hdc);
    HGDIOBJ oldbmp = SelectObject(memdc, hbitmap);
    BitBlt(memdc, 0, 0, w, h, hdc, x, y, CAPTUREBLT | SRCCOPY);
    SelectObject(memdc, oldbmp);
    BITMAPINFOHEADER infohdr = { sizeof(infohdr), w, h, 1, 32 };
    int size = w * h * 4;
    std::vector<BYTE> bits(size);
    int res = GetDIBits(hdc, hbitmap, 0, h, &bits[0],
        (BITMAPINFO*)&infohdr, DIB_RGB_COLORS);
    if (res != h)
    {
        std::cout << "errorn";
    }
    BYTE *ptr = bits.data();
    for (int y = 0; y < h; y++)
    {
        for (int x = 0; x < w; x++)
        {
            int col = x;
            int row = h - y - 1;
            int index = (row * w + col) * 4;
            BYTE blu = bits[index + 0];
            BYTE grn = bits[index + 1];
            BYTE red = bits[index + 2];
            //Seting it up
            HSV value = RGBToHSV(RGB1(red, grn, blu));
            if ((value.H > hue - tol) && (value.H < hue + tol) && (value.S > sat - maxSat) && (value.S < sat + maxSat) && (value.V > vib - maxVib) && (value.V < vib + maxVib)) {
                loc.x = x;
                loc.y = y;
                SelectObject(memdc, oldbmp);
                DeleteObject(hbitmap);
                ReleaseDC(HWND_DESKTOP, hdc);
                DeleteDC(memdc);
                return true;
            }
        }
    }

    SelectObject(memdc, oldbmp);
    DeleteObject(hbitmap);
    ReleaseDC(HWND_DESKTOP, hdc);
    DeleteDC(memdc);
    return false;
}}

我的下一个任务是开发相同的工具，可以搜索从.bmp加载的文件。到目前为止，我有这个进展：

bool LoadBMPIntoMEMDC(HDC hDC, LPCTSTR bmpfile){
HBITMAP   hBMP = (HBITMAP)LoadImage(NULL, "yellow.bmp", IMAGE_BITMAP, 0, 0, LR_LOADFROMFILE);
HDC hdc = GetDC(HWND_DESKTOP);
//SaveHBITMAPToFile("yolo.bmp", hBMP);
HDC memdc = CreateCompatibleDC(hdc);
HGDIOBJ oldbmp = SelectObject(memdc, hBMP);
//BitBlt(hdc, 0, 0, 800, 800, memdc, 0, 0, CAPTUREBLT | SRCCOPY);
//SelectObject(memdc, oldbmp);
BITMAPINFOHEADER infohdr = { sizeof(infohdr), 800, 800, 1, 24 };
int size = 800 * 800 * 3;
std::vector<BYTE> bits(size);
int res = GetDIBits(memdc, hBMP, 0, 800, &bits[0],
    (BITMAPINFO*)&infohdr, DIB_RGB_COLORS);
BYTE *ptr = bits.data();
for (int y = 0; y < 800; y++)
{
    for (int x = 0; x < 800; x++)
    {
        int col = x;
        int row = 800 - y - 1;
        int index = (row * 800 + col) * 3;
        BYTE blu = bits[index + 0];
        BYTE grn = bits[index + 1];
        BYTE red = bits[index + 2];
        //Seting it up
        HSV value = RGBToHSV(RGB1(red, grn, blu));
        std::cout << value.H << ", " << value.S << ", " << value.V << "n";
        }
    }
return true;
}

我

让它搜索一个蓝色的 100x100 bmp，它是 24 位，但从那以后我得到的值再也没有做过。 240 表示色相或每次迭代 0。

Answer 1

bool LoadBMPIntoMEMDC(LPCTSTR bmpfile, int startx, int starty, int width, int height)
{
    HBITMAP   hBMP = (HBITMAP)LoadImage(NULL, bmpfile, IMAGE_BITMAP, 0, 0, LR_LOADFROMFILE);
    HDC hdc = GetDC(HWND_DESKTOP);
    HDC memdc = CreateCompatibleDC(hdc);
    HGDIOBJ oldbmp = SelectObject(memdc, hBMP);
    BitBlt(memdc, 0, 0, width, height, memdc, startx, starty, CAPTUREBLT | SRCCOPY);
    BITMAPINFOHEADER infohdr = { sizeof(infohdr), width, height, 1, 24 };
    int size = width * height * 3;
    std::vector<BYTE> bits(size);
    int res = GetDIBits(memdc, hBMP, 0, height, &bits[0],
        (BITMAPINFO*)&infohdr, DIB_RGB_COLORS);
    BYTE *ptr = bits.data();
    for (int y = 0; y < height; y++)
    {
        for (int x = 0; x < width; x++)
        {
            int col = x;
            int row = height - y - 1;
            int index = (row * width + col) * 3;
            BYTE blu = bits[index + 0];
            BYTE grn = bits[index + 1];
            BYTE red = bits[index + 2];
        }
    }
    return true;
}