ANIMATION AND VIDEO

HOW ANIMATION AND VIDEO WORK

Individual images are projected in rapid succession. In the (movie) theater this is done at 24

frames per second (fps). On TV (NTSC) this is done at 29.97 fps.

A frame rate of at least 12 fps is necessary to keep images from appearing jerky.

A frame rate of greater than 70 fps usually does not improve the smoothness.

SOME COMPUTATIONS

A raw image from a 6 megapixel camera has approximately 6 million dots. If this is animated at 30 fps, then the total number of dots is 180 million per second or 10,800,000,000 dots per minute.

If we use 3 bytes per dot this gives 32 billion bytes per minute of video.

A two hour movie would require 4 trillion bytes of data = 45 DVDs = 15 blu-ray disks.

COMPRESSION FOR VIDEOS

MPEG-1 Video CDs (popular in Asia), some online

video, universal support on computers and DVD players

MPEG-2 DVDs, supported by all DVD players and all

computers with DVD drives with the ability to play DVD videos, One of the codecs used in Blu-Ray

MORE COMPRESSION

MPEG-4 (part 2) Internet, storage media. Slightly lower quality than

MPEG-2 but smaller size. Will hold the contents of a typical DVD on a CD. DivX, xVid

MPEG-4 (part 10) H.264 The current standard for video compression. Used in

Xbox, OS X, iPhone, among others. Very high quality with very small size.

WMV (windows media video) A series of Codecs from Microsoft that ranges from

small enough for dial-up to high enough quality for HiDef video.