Code for RubyMotion Facial Recognition Blog: http://iconoclastlabs.com/cms/blog/posts/ios-face-detection-in-rubymotion

draw_feature.rb

 def draw_feature(context, atPoint:feature_point)
    size = 6
    startx = feature_point.x - (size/2)
    starty = feature_point.y - (size/2)
    CGContextAddRect(context, [[startx, starty], [size, size]])
    CGContextDrawPath(context, KCGPathFillStroke)
  end

print_features.rb

def print_features features
    features.each_with_index do |feature, index|
      p "Found Feature!"
      
      if feature.hasLeftEyePosition
        p "Left Eye Coord: #{feature.leftEyePosition.x}x#{feature.leftEyePosition.y}"
      end
      if feature.hasRightEyePosition
        p "Right Eye Coord: #{feature.rightEyePosition.x}x#{feature.rightEyePosition.y}"
      end
      if feature.hasMouthPosition
        p "Mouth Coord: #{feature.mouthPosition.x}x#{feature.mouthPosition.y}"
      end
    end

end

translate_scale.rb

CGContextTranslateCTM(currentContext, 0, @me.size.height)
CGContextScaleCTM(currentContext, 1, -1)

viewDidLoad.rb

def viewDidLoad
    super

    view.backgroundColor = UIColor.lightGrayColor
    @me = UIImage.imageNamed("gantman.jpeg")
    cme = CIImage.alloc.initWithImage(@me)

    options = NSDictionary.dictionaryWithObject(CIDetectorAccuracyHigh, forKey:CIDetectorAccuracy)
    detector = CIDetector.detectorOfType(CIDetectorTypeFace, context:nil, options:options)

    features = detector.featuresInImage(cme)

    Dispatch::Queue.concurrent.async do
      print_features(features)
    end

end