dib

问题 I have created a consumable COM Class Library. The class library gets the image of a camera. It's of type Image / Bitmap. I consume the class library in VB6, and I need to show this image in VB6. How could I convert this System.Drawing.Image to something that VB6 can display? Can I use a DIB (using CreateDIBSection, etc.)? If yes, how exactely can a System.Drawing.Image be converted to a DIB? Thank you! 回答1: Here's what I've done in the past. First, a couple prerequisites: you get a Byte()

问题 I have an array of pixels which I need to convert to HBITMAP in order to display it in a window. I tried to use CreateDIBitmap() but I don't have the BMP headers. I tried to construct them manually according to MSDN documentation but this didn't work. Here how my code looks HBITMAP hBitmap char pixels[160*120]; // White grayscale image of size 160x120 memset(pixels,255,sizeof(pixels)); BITMAPINFOHEADER bmih; bmih.biSize = sizeof(BITMAPINFOHEADER); bmih.biWidth = 160; bmih.biHeight = -120;

问题 I am working on a program that will have many DIB bitmaps (created by CreateDIBSection ) and will have to draw a lot of text on them using Win API. In order to draw on the bitmap, Windows needs device context, created by CreateCompatibleDC . And now here are two approaches: I can create the DC once per bitmap, using it for drawing and delete it when freeing the bitmap. Or I can create DC only when I need to draw to the bitmap, call the draw functions and delete the DC. What is the better

问题 How much memory should be allocated for the DIB data received from HBITMAP using GetDIBits function? The GetDIBits function is described in MSDN as follow: int GetDIBits( __in HDC hdc, __in HBITMAP hbmp, __in UINT uStartScan, __in UINT cScanLines, __out LPVOID lpvBits, __inout LPBITMAPINFO lpbi, __in UINT uUsage ); However, the buffer to receive data lpvBits must be allocated before calling GetDIBits, because GetDIBits doesn't allocate this automatically. The question is how much memory

问题 MSDN says that the bitmap used in GetDiBits should not be selected into a DC before calling this function. But from my experience(with BitBlt ) I know that I cannot draw an a bitmap unless it is selected. How does GetDiBits circumvents this? Can I just use an unselected, newly created bitmap as argument to this function? GetDiBits as well CreateDibSection returns an array. But MSDN says about the first function: "bits of the specified compatible bitmap" I thought DI stands for

问题 This question already has answers here : Save HBITMAP to *.bmp file using only Win32 (4 answers) Closed 5 years ago . Ok, whole story is, I am trying to use Leptonica+Tesseract OCR in C++ to take a screenshot, save it to a *.bmp file, then load it back up to OCR with it. I won't need to do this frequently, but as I cannot seem to copy the screenshot data directly into a Leptonica PIX structure, I need to save it to a file first..actually a solution to this would be preferably. Here's some

问题 Good evening, I have several 32-bit images in memory buffers that I wish to "blit" to a device context, quickly. Speed is an issue here because the buffer will be manipulated constantly and need to be blitted to the DC repeatedly. The color depth of the buffer is 32-bits, so it is already in the DIB-expected format of SetDIBits(). However, this is rather cumbersome since the bitmap target of SetDIBits() cannot be already selected into the DC prior to the operation. So I will need to