Eu tentei abaixo os passos para capturar screenshot, mas tenho backround preto para MPMoviePlayerController

-(UIImage*)screenshot
{
 CGSize imageSize = [[UIScreen mainScreen] bounds].size;

CGFloat imageScale = imageSize.width / FRAME_WIDTH;

if (NULL != UIGraphicsBeginImageContextWithOptions)
    UIGraphicsBeginImageContextWithOptions(imageSize, NO, imageScale);
else
    UIGraphicsBeginImageContext(imageSize);

CGContextRef context = UIGraphicsGetCurrentContext();

for (UIWindow *window in [[UIApplication sharedApplication] windows]) 
{
    if (![window respondsToSelector:@selector(screen)] || [window screen] == [UIScreen mainScreen])
    {
        CGContextSaveGState(context);

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

        CGContextConcatCTM(context, [window transform]);

        CGContextTranslateCTM(context,
                              -[window bounds].size.width * [[window layer] anchorPoint].x,
                              -[window bounds].size.height * [[window layer] anchorPoint].y);

        [[window layer] renderInContext:context];

        CGContextRestoreGState(context);
    }
}

UIImage *image = UIGraphicsGetImageFromCurrentImageContext();

UIGraphicsEndImageContext();

return image;
}