从 SDL_Surface 到 QPixmap 的高效转换 [英] Efficient conversion from SDL_Surface to QPixmap

问题描述

我需要提取像素信息并填充要在我的 Qt 程序中使用的 QPixmap.

I need to extract pixel information and populate a QPixmap to be used in my Qt program.

我目前分两步执行此操作.

I am currently doing this in a 2-step process.

• SDL_Surface 到 Windows .bmp 使用 SDL_SaveBMP()
• .bmp 到 QImage
• QImage 到 QPixmap

我将中间 .bmp 存储在内存中.但总的来说，我对这种方法并不满意，因为它涉及与 .bmp 相关的文件格式转换开销

I am storing the intermediate .bmp in memory. But overall, I am not happy with this approach because it involves file-format conversion overheads related to .bmp

有更好的建议吗?

分享最终的工作代码，来自 jrok 的回答加上尝试像素格式

Sharing the final working code, from jrok's answer plus experimenting with pixel formats

SDL_Surface *screen = ... /* Whatever surface you want to copy from */
SDL_Surface *surface = SDL_CreateRGBSurface(SDL_SWSURFACE,
                       screen->w, screen->h,
                       24, rmask, gmask, bmask, amask);
SDL_BlitSurface(screen,NULL, surface,NULL);
QImage img(static_cast<uchar*>(surface->pixels),
                       surface->w, surface->h, QImage::Format_RGB888);

推荐答案

QImage 构造函数 获取原始图像数据.您可以从 SDL_Surface 结构中传递 pixels 指针:

SDL_Surface* surf = /* get surface */

QImage img(static_cast<uchar*>(surf->pixels), surf->w, surf->h, QImage::Format_RGB32);

最后一个参数将取决于您的 SDL_Surface 的 SDL_PixelFormat.

The last parameter will depend on the SDL_PixelFormat of your SDL_Surface.

然后你可以简单地从 QImage 制作 QPixmap :

Then you can simply make QPixmap from QImage:

QPixmap = QPixmap::fromImage(img);

QPixmap::fromImage() 参考

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