分析Kinect图像存储前首先要了解BMP格式,这里就不再重复介绍了。可参考:BMP文件格式 和 BMP文件格式详解
不管是DepthBasics-D2D还是ColorBasics-D2D,对图像的存储都使用了相同的方法。对于DepthBasics-D2D,在ProcessDepth内是这样的:
if (m_bSaveScreenshot)
{
WCHAR szScreenshotPath[MAX_PATH]; // 用来保存存储路径
// Retrieve the path to My Photos 获取存储路径
GetScreenshotFileName(szScreenshotPath, _countof(szScreenshotPath));
// Write out the bitmap to disk 把位图写入磁盘
HRESULT hr = SaveBitmapToFile(reinterpret_cast<BYTE*>(m_pDepthRGBX), nWidth, nHeight, sizeof(RGBQUAD) * 8, szScreenshotPath);
// 显示存储状态信息
WCHAR szStatusMessage[64 + MAX_PATH];
if (SUCCEEDED(hr))
{
// Set the status bar to show where the screenshot was saved
StringCchPrintf(szStatusMessage, _countof(szStatusMessage), L"Screenshot saved to %s", szScreenshotPath);
}
else
{
StringCchPrintf(szStatusMessage, _countof(szStatusMessage), L"Failed to write screenshot to %s", szScreenshotPath);
}
SetStatusMessage(szStatusMessage, 5000, true);
// toggle off so we don't save a screenshot again next frame
m_bSaveScreenshot = false;
}
而对于ProcessColor,唯一不同的是把SaveBitmapToFile函数的第一个参数 m_pDepthRGBX
改成pBuffer
。由程序前文可知,m_pDepthRGBX
和pBuffer
分别指向一个512x424大小和1920x1080大小的RGBQUAD
类型存储空间,RGBQUAD
表示一个四通道像素点,每个通道占1字节(Byte),其定义如下:
typedef struct tagRGBQUAD {
BYTE rgbBlue;
BYTE rgbGreen;
BYTE rgbRed;
BYTE rgbReserved;
} RGBQUAD;
也就是说,m_pDepthRGBX
和pBuffer
分别指向了存储一帧深度图和彩色图的存储空间。显然,对于SaveBitmapToFile来说这没有什么区别。
SaveBitmapToFile函数如下:
HRESULT CDepthBasics::SaveBitmapToFile(BYTE* pBitmapBits, LONG lWidth, LONG lHeight, WORD wBitsPerPixel, LPCWSTR lpszFilePath)
{
// 字节计数,对于深度数据是512x424x(32/8),对于彩色数据是1920x1080x(32/8)
DWORD dwByteCount = lWidth * lHeight * (wBitsPerPixel / 8);
BITMAPINFOHEADER bmpInfoHeader = {0}; // 头信息
bmpInfoHeader.biSize = sizeof(BITMAPINFOHEADER); // Size of the header 头信息大小
bmpInfoHeader.biBitCount = wBitsPerPixel; // Bit count
bmpInfoHeader.biCompression = BI_RGB; // Standard RGB, no compression 标准RGB,不压缩
bmpInfoHeader.biWidth = lWidth; // Width in pixels
bmpInfoHeader.biHeight = -lHeight; // Height in pixels, negative indicates it's stored right-side-up
bmpInfoHeader.biPlanes = 1; // Default
bmpInfoHeader.biSizeImage = dwByteCount; // Image size in bytes
BITMAPFILEHEADER bfh = {0};
bfh.bfType = 0x4D42; // 'M''B', indicates bitmap
bfh.bfOffBits = bmpInfoHeader.biSize + sizeof(BITMAPFILEHEADER); // Offset to the start of pixel data
bfh.bfSize = bfh.bfOffBits + bmpInfoHeader.biSizeImage; // Size of image + headers
// Create the file on disk to write to 创建要写入数据的文件
HANDLE hFile = CreateFileW(lpszFilePath, GENERIC_WRITE, 0, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
// Return if error opening file
if (NULL == hFile)
{
return E_ACCESSDENIED;
}
DWORD dwBytesWritten = 0;
// Write the bitmap file header 写位图文件头
if (!WriteFile(hFile, &bfh, sizeof(bfh), &dwBytesWritten, NULL))
{
CloseHandle(hFile);
return E_FAIL;
}
// Write the bitmap info header 写位图信息头
if (!WriteFile(hFile, &bmpInfoHeader, sizeof(bmpInfoHeader), &dwBytesWritten, NULL))
{
CloseHandle(hFile);
return E_FAIL;
}
// Write the RGB Data 写入RGB数据
if (!WriteFile(hFile, pBitmapBits, bmpInfoHeader.biSizeImage, &dwBytesWritten, NULL))
{
CloseHandle(hFile);
return E_FAIL;
}
// Close the file
CloseHandle(hFile);
return S_OK;
}
发现没什么要特别说明的,对照前面的BMP格式说明很好理解,就这样吧(逃