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2016-04-22 09:55:46 -0500 commented question OpenCV Error Assertion failed <s >=0> in cv::setSize, file C:\builds\master_PackSlave-win64-vc12-shared\opencv\modules\core\src\matric.cpp, line 306

i still can't solve the bug, could you teach me. well the problem is, the code is works fine when capture screen, but when to capture something rendered like youtube or streaming, here it goes the code stuck at something at sizeof() , now, i can't identify which one or where

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2016-04-20 04:59:08 -0500 commented question OpenCV Error Assertion failed <s >=0> in cv::setSize, file C:\builds\master_PackSlave-win64-vc12-shared\opencv\modules\core\src\matric.cpp, line 306

if this RECT reference is right : https://msdn.microsoft.com/en-us/libr... , then there's a problem in RECT function, (actually i didn't write that function, but it works using OPENCV for my goal) , and actually my goal is Capture Desktop or specific window as source in OPENCV and that function is create a bitmap from the screen image and loop it , am i doing right so far in your opinion ?

2016-04-20 04:14:34 -0500 commented question OpenCV Error Assertion failed <s >=0> in cv::setSize, file C:\builds\master_PackSlave-win64-vc12-shared\opencv\modules\core\src\matric.cpp, line 306

yes it goes to cccccccc , how to set to 0xcc ?

2016-04-20 04:01:08 -0500 commented question OpenCV Error Assertion failed <s >=0> in cv::setSize, file C:\builds\master_PackSlave-win64-vc12-shared\opencv\modules\core\src\matric.cpp, line 306

because it is minus ? the return is int ?

2016-04-20 03:37:16 -0500 commented question OpenCV Error Assertion failed <s >=0> in cv::setSize, file C:\builds\master_PackSlave-win64-vc12-shared\opencv\modules\core\src\matric.cpp, line 306

i use this : printf("width : %d\n, height : %d\n", width, height); system("PAUSE"); it gives me with width : -858993460 height : -858993460 , can you tell me what is happen ?

2016-04-19 23:35:04 -0500 commented answer OpenCV Error: Assertion failed (s >= 0) in setSize

hi, can you answer my error too ? http://answers.opencv.org/question/93...

2016-04-19 23:27:07 -0500 received badge  Editor (source)
2016-04-19 23:24:35 -0500 asked a question OpenCV Error Assertion failed <s >=0> in cv::setSize, file C:\builds\master_PackSlave-win64-vc12-shared\opencv\modules\core\src\matric.cpp, line 306

when i try to compile this code, it gives me then, Unhandled exception at 0x000000xxxx in video input.exe: Microsoft C++ exception: cv::Exception at memory location 0x0000000000xxxxxx then thrown me to mat.inl.hpp line 306 maybe it has to do with this function :

Mat hwnd2mat(HWND hwnd)
{
    HDC hwindowDC, hwindowCompatibleDC;
    int height, width, srcheight, srcwidth;
    HBITMAP hbwindow;
    Mat src;
    BITMAPINFOHEADER  bi;

    hwindowDC = GetDC(hwnd);
    hwindowCompatibleDC = CreateCompatibleDC(hwindowDC);
    SetStretchBltMode(hwindowCompatibleDC, COLORONCOLOR);

    RECT windowsize;    // get the height and width of the screen
    GetClientRect(hwnd, &windowsize);

    srcheight = windowsize.bottom;
    srcwidth = windowsize.right;
    height = windowsize.bottom /1.1;  //change this to whatever size you want to resize to
    width = windowsize.right /1.1;

    src.create(height, width, CV_8UC4);

    // create a bitmap
    hbwindow = CreateCompatibleBitmap(hwindowDC, width, height);
    bi.biSize = sizeof(BITMAPINFOHEADER);    //http://msdn.microsoft.com/en-us/library/windows/window/dd183402%28v=vs.85%29.aspx
    bi.biWidth = width;
    bi.biHeight = -height;  //this is the line that makes it draw upside down or not
    bi.biPlanes = 1;
    bi.biBitCount = 32;
    bi.biCompression = BI_RGB;
    bi.biSizeImage = 0;
    bi.biXPelsPerMeter = 0;
    bi.biYPelsPerMeter = 0;
    bi.biClrUsed = 0;
    bi.biClrImportant = 0;

    // use the previously created device context with the bitmap
    SelectObject(hwindowCompatibleDC, hbwindow);
    // copy from the window device context to the bitmap device context
    StretchBlt(hwindowCompatibleDC, 0, 0, width, height, hwindowDC, 0, 0, srcwidth, srcheight, SRCCOPY); //change SRCCOPY to NOTSRCCOPY for wacky colors !
    GetDIBits(hwindowCompatibleDC, hbwindow, 0, height, src.data, (BITMAPINFO *)&bi, DIB_RGB_COLORS);  //copy from hwindowCompatibleDC to hbwindow

    // avoid memory leak
    DeleteObject(hbwindow);
    DeleteDC(hwindowCompatibleDC);
    ReleaseDC(hwnd, hwindowDC);

    return src;
}
2016-04-16 01:49:11 -0500 commented answer Ip / network camera access.

i have the url of streaming camera, but can you write the whole code in example, i'm still ambiguity about your code