// Render the UIView into the CGContextRef using the

// -[CALayer renderInContext:] method

- (void)renderView:(UIView*)view inContext:(CGContextRef)context

{

    // -renderInContext: renders in the coordinate space of the layer,

    // so we must first apply the layer's geometry to the graphics context

    CGContextSaveGState(context);

    // Center the context around the window's anchor point

    CGContextTranslateCTM(context, [view center].x, [view center].y);

    // Apply the window's transform about the anchor point

    CGContextConcatCTM(context, [view transform]);

    // Offset by the portion of the bounds left of and above the anchor point

    CGContextTranslateCTM(context,

                          -[view bounds].size.width * [[view layer] anchorPoint].x,

                          -[view bounds].size.height * [[view layer] anchorPoint].y);

    // Render the layer hierarchy to the current context

    [[view layer] renderInContext:context];

    // Restore the context

    CGContextRestoreGState(context);

}

// capture the camera content using AV Foundation as described in Technical Q&A QA1702

// Delegate routine that is called when a sample buffer was written

- (void)captureOutput:(AVCaptureOutput *)captureOutput

didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer

       fromConnection:(AVCaptureConnection *)connection

{

    // Create a UIImage from the sample buffer data

    UIImage *image = [self imageFromSampleBuffer:sampleBuffer];

    // Create a graphics context with the target size

    CGSize imageSize = [[UIScreen mainScreen] bounds].size;

    UIGraphicsBeginImageContextWithOptions(imageSize, NO, 0);

    CGContextRef context = UIGraphicsGetCurrentContext();

    // Draw the image returned by the camera sample buffer into the context.

    // Draw it into the same sized rectangle as the view that is displayed on the screen.

    float menubarUIOffset = 44.0;

    UIGraphicsPushContext(context);

    [image drawInRect:CGRectMake(0, 0, imageSize.width, imageSize.height-menubarUIOffset)];

    UIGraphicsPopContext();

    // Render the camera overlay view into the graphic context that we created above.

    [self renderView:overlay.view inContext:context];

    // Retrieve the screenshot image containing both the camera content and the overlay view

    UIImage *screenshot = UIGraphicsGetImageFromCurrentImageContext();

    UIGraphicsEndImageContext();

}

// Render the UIView into the CGContextRef using the

// CALayer/-renderInContext: method

- (void)renderView:(UIView*)view inContext:(CGContextRef)context

{

    // -renderInContext: renders in the coordinate space of the layer,

    // so we must first apply the layer's geometry to the graphics context

    CGContextSaveGState(context);

    // Center the context around the window's anchor point

    CGContextTranslateCTM(context, [view center].x, [view center].y);

    // Apply the window's transform about the anchor point

    CGContextConcatCTM(context, [view transform]);

    // Offset by the portion of the bounds left of and above the anchor point

    CGContextTranslateCTM(context,

                          -[view bounds].size.width * [[view layer] anchorPoint].x,

                          -[view bounds].size.height * [[view layer] anchorPoint].y);

    // Render the layer hierarchy to the current context

    [[view layer] renderInContext:context];

    // Restore the context

    CGContextRestoreGState(context);

}

// this get called when an image has been taken from the camera

- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info

{

    UIImage *image = [info valueForKey:UIImagePickerControllerOriginalImage];

    CGSize imageSize = [[UIScreen mainScreen] bounds].size;

    if (NULL != UIGraphicsBeginImageContextWithOptions)

        UIGraphicsBeginImageContextWithOptions(imageSize, NO, 0);

    else

        UIGraphicsBeginImageContext(imageSize);

    CGContextRef context = UIGraphicsGetCurrentContext();

    // Draw the image returned by the camera sample buffer into the context.

    // Draw it into the same sized rectangle as the view that is displayed on the screen.

    float menubarUIOffset = 44.0;

    UIGraphicsPushContext(context);

    [image drawInRect:CGRectMake(0, 0, imageSize.width, imageSize.height-menubarUIOffset)];

    UIGraphicsPopContext();

    // Render the camera overlay view into the graphic context that we created above.

    [self renderView:overlay.view inContext:context];

    // Retrieve the screenshot image containing both the camera content and the overlay view

    UIImage *screenshot = UIGraphicsGetImageFromCurrentImageContext();

    UIGraphicsEndImageContext();

}