The first photograph, taken in 1826, required an eight-hour exposure time and produced a blurry gray image. By 1850, a photographic process called "daguerreotype" made picture taking practical, and daguerreotype studios became a cutting-edge business venture. Innovations such as color film, flash units, and instant cameras popularized photography. By 1950, everyone was taking "snapshots" of special events, holidays, kids, and pets. Photography has now gone digital, and advances in 3-D computer graphics and animations have unleashed entire industries for movie special effects and computer games.

Section A of this unit takes a close look at bitmap graphics-the most popular graphics for photographs and Web use. Section B then moves to a different type of graphics, called "vector graphics," which are often used for clip art and provide the underlying technology for 3-D graphics and 3-D animations. Section C explores desktop video technology. You've probably encountered it on the Web or wondered if you could use it to edit out embarrassing moments from your vacation videos. Section D is all about digital sound. It includes information about the wildly popular MP3 music format, along with tips about composing MIDI music and combining voice recognition with word processing. The TechTalk section delves into compression-you'll find out how it works and learn how to use a popular compression utility.

When you complete this unit, you should be able to:

Describe the advantages, disadvantages, and uses for digital media, such as bitmap graphics, vector graphics, 3-D graphics, 3-D animations, desktop video, waveform audio. MIDI music, speech synthesis, and speech recognition

List the equipment and software that can be used to work with various types of digital media

Identify digital media files by their filename extensions

Understand the advantages and disadvantages of using each type of digital media on the Web

Explain how resolution, image size, color depth, and color palettes can be manipulated to adjust the file size of a bitmap graphic

Describe the procedures required to convert bitmap graphics into vectors and vector graphics into bitmaps

Explain how wireframes, rendering, and ray tracing apply to 3-D graphics

Define the differences between desktop video and 3-D animation

Describe how to shoot, capture, edit, and process desktop video

Explain how window size, frame rate, and compression affect file size for a desktop video

Describe the process of creating an MP3 music file