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objective c - Overlay an image over another image in iOS

i am displaying thumbnail images from youtube in my iOS app. which upon click, will go to youtube.

I need a way of overlaying a play button onto those images. What might be the most straightforward way of doing so?

Also, the images are remotely loaded onto a table, so performance is a big consideration

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If you are concerned with table scrolling performance, retrieve the thumbnail and paint the play button over it.

+(UIImage*) drawImage:(UIImage*) fgImage
              inImage:(UIImage*) bgImage
              atPoint:(CGPoint)  point
{
    UIGraphicsBeginImageContextWithOptions(bgImage.size, FALSE, 0.0);
    [bgImage drawInRect:CGRectMake( 0, 0, bgImage.size.width, bgImage.size.height)];
    [fgImage drawInRect:CGRectMake( point.x, point.y, fgImage.size.width, fgImage.size.height)];
    UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();

    return newImage;
}

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