C++ Windows下屏幕截图

屏幕截图核心代码（如果要求高帧率，请使用DxGI）：

// RGB到YUV的转换公式
#define RGB_TO_Y(r, g, b) ((int)((0.299 * (r)) + (0.587 * (g)) + (0.114 * (b))))
#define RGB_TO_U(r, g, b) ((int)((-0.169 * (r)) - (0.331 * (g)) + (0.500 * (b)) + 128))
#define RGB_TO_V(r, g, b) ((int)((0.500 * (r)) - (0.419 * (g)) - (0.081 * (b)) + 128))// 假设输入图像是32位ARGB，宽度为width，高度为height，如果是图像是RGB，下面像素位数4改为3即可
void ConvertRGBToYUV420P(unsigned char* rgbData, int width, int height, unsigned char* yuvData)
{int ySize = width * height;int uvSize = width * height / 4;// 填充Y分量for (int i = 0; i < height; ++i){for (int j = 0; j < width; ++j){int index = i * width + j;yuvData[index] = RGB_TO_Y(rgbData[index * 4], rgbData[index * 4 + 1], rgbData[index * 4 + 2]);}}// 填充U和V分量（下采样）int uvIndex = ySize;for (int i = 0; i < height; i += 2){for (int j = 0; j < width; j += 2){int rgbIndex = i * width + j;yuvData[uvIndex++] = RGB_TO_U(rgbData[rgbIndex * 4], rgbData[rgbIndex * 4 + 1], rgbData[rgbIndex * 4 + 2]);}}for (int i = 0; i < height; i += 2){for (int j = 0; j < width; j += 2){int rgbIndex = i * width + j;yuvData[uvIndex++] = RGB_TO_V(rgbData[rgbIndex * 4], rgbData[rgbIndex * 4 + 1], rgbData[rgbIndex * 4 + 2]);}}
}void SaveYUV420P(const char* filename, unsigned char* yuvBuffer, int width, int height)
{FILE* file = fopen(filename, "wb");if (!file){AfxMessageBox(_T("Failed to open file for writing!"));return;}int frameSize = width * height * 3 / 2;fwrite(yuvBuffer, 1, frameSize, file);fclose(file);
}void SaveHBitmapToBmpFile(HBITMAP hBitmap, CString path)
{// 定义文件头结构BITMAPFILEHEADER fileHead;int fileHeadLen = sizeof(BITMAPFILEHEADER);// 定义图象信息结构BITMAPINFOHEADER bmpHead;int bmpHeadLen = sizeof(BITMAPINFOHEADER);// 获取HBITMAP对象信息BITMAP bmpObj;GetObject(hBitmap, sizeof(BITMAP), &bmpObj);// 计算文件总的字节大小DWORD fileSizeInByte;CDC srcDC;srcDC.CreateDC(L"DISPLAY", NULL, NULL, NULL);DWORD PixelSizeInBit = srcDC.GetDeviceCaps(BITSPIXEL) * srcDC.GetDeviceCaps(PLANES);fileSizeInByte = fileHeadLen + bmpHeadLen + bmpObj.bmWidth * bmpObj.bmHeight * PixelSizeInBit / 8;// 初始化文件头结构fileHead.bfOffBits = fileHeadLen + bmpHeadLen;fileHead.bfReserved1 = 0;fileHead.bfReserved2 = 0;fileHead.bfSize = fileSizeInByte;fileHead.bfType = 0x4D42; // 'BM'// 初始图像信息结构bmpHead.biBitCount = PixelSizeInBit;bmpHead.biClrImportant = 0;bmpHead.biClrUsed = 0;bmpHead.biCompression = BI_RGB;bmpHead.biHeight = -bmpObj.bmHeight;//图像数据颠倒处理bmpHead.biPlanes = 1;bmpHead.biSize = bmpHeadLen;bmpHead.biSizeImage = bmpObj.bmWidth * bmpObj.bmHeight * PixelSizeInBit / 8;bmpHead.biWidth = bmpObj.bmWidth;bmpHead.biXPelsPerMeter = 0;bmpHead.biYPelsPerMeter = 0;// 创建并打开BMP文件CFile file;if (!file.Open(path, CFile::modeCreate | CFile::modeWrite)){// 处理文件打开失败的情况return;}// 写入文件头和图象信息头file.Write(&fileHead, fileHeadLen);file.Write(&bmpHead, bmpHeadLen);// 获取位图数据并写入文件BYTE* pBitmapBits = NULL;BITMAPINFO bmpInfo;ZeroMemory(&bmpInfo, sizeof(BITMAPINFO));bmpInfo.bmiHeader = bmpHead;HDC hDC = GetDC(NULL);HBITMAP hOldBitmap = (HBITMAP)SelectObject(hDC, hBitmap);pBitmapBits = new unsigned char[bmpHead.biSizeImage];int nBits = GetDIBits(hDC, hBitmap, 0, bmpObj.bmHeight, pBitmapBits, &bmpInfo, DIB_RGB_COLORS);file.Write(pBitmapBits, bmpHead.biSizeImage);// 转换RGB到YUV420Punsigned char* yuvBuffer = new unsigned char[bmpObj.bmWidth * bmpObj.bmHeight * 3 / 2];ConvertRGBToYUV420P(pBitmapBits, bmpObj.bmWidth, bmpObj.bmHeight, yuvBuffer);SaveYUV420P("d:\\a.yuv", yuvBuffer, bmpObj.bmWidth, bmpObj.bmHeight);delete[] yuvBuffer;// 恢复原来的位图对象并释放资源SelectObject(hDC, hOldBitmap);ReleaseDC(NULL, hDC);delete[] pBitmapBits;// 关闭文件file.Close();
}// 获取屏幕截图
HBITMAP CaptureScreen()
{HDC hScreen = GetDC(NULL);HDC hDC = CreateCompatibleDC(hScreen);int width = GetSystemMetrics(SM_CXSCREEN);int height = GetSystemMetrics(SM_CYSCREEN);HBITMAP hBitmap = CreateCompatibleBitmap(hScreen, width, height);SelectObject(hDC, hBitmap);BitBlt(hDC, 0, 0, width, height, hScreen, 0, 0, SRCCOPY);DeleteDC(hDC);ReleaseDC(NULL, hScreen);return hBitmap;
}void CaptureAndSaveScreenAsYUV420P(const char* filename)
{HBITMAP hBitmap = CaptureScreen();SaveHBitmapToBmpFile(hBitmap, _T("d:\\a.bmp"));DeleteObject(hBitmap);
}CaptureAndSaveScreenAsYUV420P("d:\\a.yuv");

该代码包含了抓取屏幕数据获取到HBITMAP对象，并根据HBITMAP对象获取到RGB数据，RGB数据可以保存bmp文件，也可以转换YUV420P后进行图像编码，具体如何使用，各取所需吧。