c++ - 将 cv::Mat 转换为 SDL_Texture

Question

我正在尝试使用 SDL 播放视频。为此，我使用 opencv 加载视频并获取帧。然后我只需要将这些帧转换为 SDL_Texture*，然后我就可以在屏幕上绘制它们了。

那是我的问题，我正在将其转换为 SDL_Surface*，但随后转换为 SDL_Texture 失败，我不确定原因。这是我的代码:

void Cutscene::play()
{
  this->onLoop();
  this->onRender();

  while(!frameMat.empty())
  {
    this->onLoop();
    this->onRender();
  }
}

void Cutscene::onLoop()
{
  video >> frameMat;

  convertCV_MatToSDL_Texture();
}

void Cutscene::onRender()
{
  Image::onDraw(GameEngine::getInstance()->getRenderer(), frameTexture);

}

void Cutscene::convertCV_MatToSDL_Texture()
{
  IplImage opencvimg2 = (IplImage)frameMat;
  IplImage* opencvimg = &opencvimg2;

  //Convert to SDL_Surface
  frameSurface = SDL_CreateRGBSurfaceFrom((void*)opencvimg->imageData,
                         opencvimg->width, opencvimg->height,
                         opencvimg->depth*opencvimg->nChannels,
                         opencvimg->widthStep,
                         0xff0000, 0x00ff00, 0x0000ff, 0);

  if(frameSurface == NULL)
  {
    SDL_Log("Couldn't convert Mat to Surface.");
    return;
  }

  //Convert to SDL_Texture
  frameTexture = SDL_CreateTextureFromSurface(
                    GameEngine::getInstance()->getRenderer(), frameSurface);
  if(frameTexture == NULL)
  {
    SDL_Log("Couldn't convert Mat(converted to surface) to Texture."); //<- ERROR!!
    return;
  }

  //cvReleaseImage(&opencvimg);
  //MEMORY LEAK?? opencvimg opencvimg2
}

我在我项目的其他部分使用了这个函数 SDL_CreateTextureFromSurface 并且它在那里工作。所以问题是:你知道我在代码中进行的转换有什么问题吗？如果没有，是否有更好的方法来完成我想做的事情？

Answer 1

我成功了!我认为唯一的问题是我必须使用 &frameMat 而不是 frameMat。如果有人感兴趣，这是我的代码:

SDL_Texture* Cutscene::convertCV_MatToSDL_Texture(const cv::Mat &matImg)
{
    IplImage opencvimg2 = (IplImage)matImg;
    IplImage* opencvimg = &opencvimg2;

     //Convert to SDL_Surface
    frameSurface = SDL_CreateRGBSurfaceFrom(
                         (void*)opencvimg->imageData,
                         opencvimg->width, opencvimg->height,
                         opencvimg->depth*opencvimg->nChannels,
                         opencvimg->widthStep,
                         0xff0000, 0x00ff00, 0x0000ff, 0);

    if(frameSurface == NULL)
    {
        SDL_Log("Couldn't convert Mat to Surface.");
        return NULL;
    }

    //Convert to SDL_Texture
    frameTexture = SDL_CreateTextureFromSurface(
                    GameEngine::getInstance()->getRenderer(), frameSurface);
    if(frameTexture == NULL)
    {
        SDL_Log("Couldn't convert Mat(converted to surface) to Texture.");
        return NULL;
    }
    else
    {
        SDL_Log("SUCCESS conversion");
        return frameTexture;
    }

    cvReleaseImage(&opencvimg);