Computer Vision – Face Detection

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Computer Vision Face Detection

• Posted by Anurag Jain

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COMPUTER VISION

• What is it?
• Computer Vision is mimicking the abilities of
  human vision by electronically perceiving and
  understanding an image.
• It is a broad term and includes a lot of domains
  like Gesture Recognition, Optical Character
  Recognition, Face detection and a lot more.
• In this article, we will be focussing on face
  detection and try to understand the key ideas
  that allow us to detect human faces in real time.

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It all begins with a pixel!

• As shown below, a digital representation of an
  image comprises a large number of pixels
  depending on the resolution of the image.
• Each pixel represents the smallest unit
  containing the information about how the image
  will be rendered on a digital device.
• Each pixel can be represented by 4 bytes ( 1 byte
  each for red, green, blue and alpha ).

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What Face Detection is?

• It is essentially processing a raw image to
• Detect the presence of human faces, if any.
• Extract info about the coordinates and size of
  those human faces.
• How do we do it?
• Thats what this article is all about.
• Before we dive into the implementation details,
  lets discuss the framework that most of the
  modern face detection systems use the
  Viola-Jones Object Detection Framework.

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VIOLA JONES OBJECT DETECTION FRAMEWORK

• The training is slow, but the detection is fast.
• This framework introduced three key ideas
• Integral image representation
• Construction of classifier by Adaptive Boosting
• Combining successively more complex classifiers
  in a cascade structure
• More detail - http//vinsol.com/blog/2016/06/28/co
  mputer-vision-face-detection/