Reading Guide for "Image Compression" and "Video Compression"

  1. A 200 by 200 pixel image using 3 bytes (24 bits) per pixel will use how many kilobytes of space? 

    ___117.1975 kilobytes___________________________

  2. Define "lossy compression".  Lossy compression means that some of the original data in the image

    is lost when the image is compressed.

  3. A video can be thought of as a series of   still images shown one after another in quick succession


  4. How many KB (kilobytes) of storage space would it take to store one second of a small video of

    dimensions 640 x 480?  ____ 21,600 KB_________________________

  5. Why is it important, nay, crucial, that videos be compressed? _If videos were not compressed, they

    would be so large in size that you could only store about 4 minutes of 640x480 video on a DVD.


  6. Briefly explain the two basic methods to compress video.  _Spatial encoding takes advantage of

    similarities within a single frame of a movie.  Temporal encoding takes advantage of similarities

    between multiple successive frames of a video.

  7. Complete this sentence: "Most commonly used video compression systems are variations of _MPEG___."