Pong Sketch Two Project

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Pong Sketch Two Project

• Jin Fan
• Jessica Yu

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Pong design concept

• What is it?
• An interactive environment that incorporates
  camera motion detection, media object, sound and
  projections.
• Inspired by the electronic ping pong game, our
  project takes it one step further by allowing
  participants to use their whole body and gestures
  to interact with the graphic ball.
• In the installation, users motions are tracked
  through a video camera, which is then projected
  onto a screen as a silhouette along with a
  computer generated bouncing ball (refer to image)
• Users presence cause the ball to physically
  bounce off their silhouette on the screen.
• Users can experiment with interactive
  possibilities (i.e. Multiple players trying to
  pass the ball to each other rather than a single
  interactive experience.

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Quality of Motion

• Space-oriented - user motions and gestures are
  direct and expressed within the defined space.
• Common motions- waving, kicking, jumping,
  ducking or positioning their body to form a shape
  in order to trap the ball in a corner.
• Iconic gestures - i.e. users move their hands
  downward towards the ball repetitively since they
  associate this gesture to the motion of dribbling
  a ball

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Technical Aspects
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Input Output

• Input Participants movements and body gestures
  as captured by the video camera device.
• Output Projected image on the screen (digital
  bouncing ball, silhouette) Sound

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Approach to sensing

• MAX MSP function to detect Point of Contact
• Convert both input values to grey scale
• Multiplies the value of each white area by 0.5
• When both white areas (the ball and the blob)
  overlap, their value adds up to 1. T
• Allows us to determine the point of contact and
  program the resulting bouncing motion by locating
  the white blob in the screen that possesses the
  value of 1.
• Brightness thresholding
• Detects luminosity between the foreground users
  and the background environment.
• Isolate users from the background in the video
  input and detect the users movements.

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Code Process
These are the 4 stages we drew to analyze
different positions of the ball in order to
achieve the bouncing action.
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Research similar projects

• 1. IDEO multi-touch prototype
  http//labs.ideo.com/2008/12/08/quick-n-dirty-mult
  i-touch-flash-api-wiimote/
• Use of Wiimote andflash application to turn a
  projection surface into a multi-touch
  environment. Our project was inspired by this
  ping pong interaction through using physical
  movements and projections.
• 2. Virtual Ping Pong game http//www.wansvision.
  com/pingpong.html
• A system that measures hand movements and move
  the paddle accordingly. Our project takes it one
  step further by allowing participants to interact
  with their whole body rather than just limited to
  hands.

1.
2.
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Research - Theory

• http//www.flong.com/texts/essays/essay_cvad/
• - This article discusses basic mechanism of
  computer vision and how it can be applied in
  different situations and purposes.
• - Outlined some elementary tracking and
  overlapping detection techniques that is
  applicable to the construction of our project
  (refer to image below).
• http//a.parsons.edu/jonah/jonah_thesis.pdf
• - Outlines Jonahs theories and advantages of
  computer vision.
• - Articulate concepts behind computer
  vision and how to incorporate it in order to
  create a successful interactive environment for
  the audience (i.e. expressive interactions,
  interactive mapping, use of whole body, etc.).

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Experiences

• No restrictions to wires or hardware since the
  only input device is the camcorder. This
  promotes a more natural, continuous and physical
  experience.
• With the application of computer vision, we have
  more flexibility in terms of the type of
  interaction and actions versus the original
  version of pong, which requires the use of a
  joystick controller.
• One drawback is that there is no centre of
  gravity programmed within the environment. This
  causes the experience appears less realistic
  since the ball bounces the same way and in speed
  regardless of the amount of force we applied to
  it.