In today's project, you learn to use an important computer science concept, conditional statements.

You used a conditional statement to change individual pixels in a project.

Conditional statements help computer scientists create digital effects for photographs and pictures.

The basic idea of scanning an image for pixels that match a condition has incredible applications in the real world.

Using this technology, computer scientists like you program a computer to recognize something based on its color or shape.

In this video, a computer is analyzing a video in real time to track a person as he walks.

The image in the upper right corner represents what the person looks like.

And the green rectangle shows where the computer thinks the person is.

This is useful for a lot of reasons.

For example, motion capture uses the movements of real people or animals to create more realistic virtual worlds in video games and movies.

Special dots attached to actors' faces and bodies allow cameras to track their movements and facial expressions.

This tracking data provides information to computer scientists on how to create movies and virtual worlds.

Other examples of tracking programs that use conditional statements are cars that can drive themselves and recognize stop signs and pedestrians and programs that aromatically organize and tag photos.

Video chats with friends are more fun when you can give each other silly sunglasses and hats.

These things are made possible today by computer science and computer scientists.

Computer science is very useful in art and the entertainment industry, as well as in our everyday lives.

If you take a high school or college computer science class, then you may learn about computer aided art techniques and digital design tools.

Knowing a bit of computer science will help you learn how these tools function so you will know how to better use them.

Next session, you will build a stamping project that lets you design your own buildings.

Until next time, have fun creating and coding.

  • "E03 - The Technology" by Joel Bennett ( -- Licensed by Creative Commons Attribution 3.0 Unported ( -- Video trimmed to needed length | Audio removed
  • "Face detection" by Beatrice Murch ( -- Licensed by CC BY 2.0 ( -- Image scaled up, cropping edges | Edges rounded
  • "Particle Filter Object Tracking - Person Crossing" by Kevin Schluff ( -- Licensed by Creative Commons Attribution 3.0 Unported ( -- Video scaled up, cropping edges | Audio Removed | Video trimmed to needed length