I have managed to get this working so sharing the solution incase anyone else needs to do the same.

I have added a method to the VuforiaEAGLView instance that takes the pixels rendered from the buffer and creates an image that is the same size as the viewport. 

- (UIImage*) snapshot {

    UIImage *outputImage = nil;

   

    // Setup pixel stream sizes

    CGFloat scale = [[UIScreen mainScreen] scale];

    static const size_t kComponentsPerPixel = 4;

    static const size_t kBitsPerComponent = sizeof(unsigned char) * 8;

    CGRect s = CGRectMake(0,0, (self.frame.size.width * scale), (self.frame.size.height * scale));

    glViewport(0, 0, s.size.width, s.size.height);

    size_t bufferLength = s.size.width * s.size.height * kComponentsPerPixel;

    GLubyte* buffer = (GLubyte*) malloc(bufferLength);

   

    // Get the pixels for the defined screen size and create a CG image

    glReadPixels(0, 0, s.size.width, s.size.height, GL_RGBA, GL_UNSIGNED_BYTE, buffer);

   

    CGDataProviderRef ref = CGDataProviderCreateWithData(NULL, buffer, s.size.width * s.size.height * 4, NULL);

   

    CGImageRef iref = CGImageCreate(s.size.width, s.size.height, 8, 32, s.size.width * 4, CGColorSpaceCreateDeviceRGB(), kCGBitmapByteOrderDefault, ref, NULL, true, kCGRenderingIntentDefault);

   

    size_t width = CGImageGetWidth(iref);

   

    size_t height = CGImageGetHeight(iref);

   

    size_t length = width * height * 4;

   

    uint32_t *pixels = (uint32_t *)malloc(length);

   

    CGContextRef context1 = CGBitmapContextCreate(pixels, width, height, 8, width * 4, CGImageGetColorSpace(iref), kCGImageAlphaNoneSkipFirst | kCGBitmapByteOrder32Big);

   

   

    // Flip the dimensions

    CGAffineTransform transform = CGAffineTransformIdentity;

    transform = CGAffineTransformMakeTranslation(0.0f, height);

    transform = CGAffineTransformScale(transform, 1.0, -1.0);

   

    // Redraw the image

    CGContextConcatCTM(context1, transform);

   

    CGContextDrawImage(context1, CGRectMake(0.0f, 0.0f, width, height), iref);

   

    CGImageRef outputRef = CGBitmapContextCreateImage(context1);

   

    // Create the UI image

    outputImage = [UIImage imageWithCGImage: outputRef];

   

    // Release from memory

    CGDataProviderRelease(ref);

    CGImageRelease(iref);

    CGContextRelease(context1);

    CGImageRelease(outputRef);

    free(pixels);

    free(buffer);

   

    return outputImage;

   

}

Hi Strasza,

I have tried something very similar to this by getting a frame image from the presenting view (example below). The Vuforia::Frame only provides the background view from the camera but I need to get augmented scene in the same image. Is there a way to do that?

- (UIImage*)renderFrameIntoImage

{

    @synchronized(self)

    {

      

        Vuforia::setFrameFormat(Vuforia::RGB888, true);

        Vuforia::State state = Vuforia::Renderer::getInstance().begin();

        Vuforia::Frame frame = state.getFrame();

        int frameCount = frame.getNumImages();

      

        UIImage* image = NULL;

      

        if(frameCount > 0){

          

            int lastFrame = frameCount-1;

          

            const Vuforia::Image *qcarImage = frame.getImage(lastFrame);

            NSLog(@"Creating frame image %d   pixel format  %d", lastFrame, qcarImage->getFormat() );

          

            image = [self createUIImage:qcarImage];

          

        }

      

      

      

        Vuforia::Renderer::getInstance().end();

      

        return image;

      

    }

  

}

- (UIImage *)createUIImage:(const Vuforia::Image *)qcarImage

{

    int width = qcarImage->getWidth();

    int height = qcarImage->getHeight();

    int bitsPerComponent = 8;

    int bitsPerPixel = Vuforia::getBitsPerPixel(Vuforia::RGB888);

    int bytesPerRow = qcarImage->getBufferWidth() * bitsPerPixel / bitsPerComponent;

    CGColorSpaceRef colorSpaceRef = CGColorSpaceCreateDeviceRGB();

    CGBitmapInfo bitmapInfo = kCGBitmapByteOrderDefault | kCGImageAlphaNone;

    CGColorRenderingIntent renderingIntent = kCGRenderingIntentDefault;

  

    CGDataProviderRef provider = CGDataProviderCreateWithData(NULL, qcarImage->getPixels(), Vuforia::getBufferSize(width, height, Vuforia::RGB888), NULL);

  

    CGImageRef imageRef = CGImageCreate(width, height, bitsPerComponent, bitsPerPixel, bytesPerRow, colorSpaceRef, bitmapInfo, provider, NULL, NO, renderingIntent);

    UIImage *image = [UIImage imageWithCGImage:imageRef];

  

    CGDataProviderRelease(provider);

    CGColorSpaceRelease(colorSpaceRef);

    CGImageRelease(imageRef);

  

    return image;

}

Hello,

This article explains how to get the camera frame in Vuforia: https://library.vuforia.com/content/vuforia-library/en/articles/Solution/Working-with-the-Camera.html#How-To-Access-the-Camera-Image-in-Native

Is this what you are having issues with?

Thanks,

-Vuforia Support

Did you manage to find a solution for this? I am trying to do the same thing but struggling to find a way that works reliably.

The closest I have got so far is to snapshot both the Frame and Scene renderer and put them together but the camera frame sometimes produces a messed up image and always landscape dimension