In the past few years, the term digital video has taken on a variety of new meanings. To the consumer, digital video might simply mean shooting video with the latest video camera from Canon, Sony, or JVC.
A digital video camera is named as such because the picture information is stored as a digital signal. The camera can translate the picture data into digital signals—saving it on tape in much the same way that your computer saves data to a hard disk.
Older systems that don’t store data digitally to tape, store the information in an analog format on tape. In analog format, information is sent in waves rather than as specific individual bits of data. For video clips, stills, and audio information to be used by Premiere, they must be converted to digital format.
Video and audio information stored in digital format from digital video cameras can be transferred directly to the computer (provided you have an IEEE1394 port. Apple’s IEEE port is called FireWire). Because the data is already digitized, the IEEE1394 port provides a fast means of transferring the data.
If you wish to use video clips shot on an analog video camera or recorded on an analog video deck, the clips must be digitized. Analog-to-digital capture boards that can be installed in both PCs and Macs generally handle this process. These boards digitize both audio and video.
Other types of visual information, such as photographs and slides, also need to be converted to digital signals before they are loaded into Premiere. Scanners often digitize slides and still images, or they can be shot by still digital cameras. During the scanning process, the still image is saved to the computer’s hard disk and can be loaded directly into Premiere.
Digital video provides numerous advantages over traditional analog video. If you use a digital video camera, your video clips are generally superior to analog clips. In digital video, you can freely duplicate video and audio without losing quality.
In traditional analog video, each time you copy a clip, you “go down” a generation— thus losing a little quality. In the context of Premiere, one advantage of digital video is that it enables you to edit video nonlinearly. In traditional video, the production is created piece-by-piece on videotape—in a linear manner.
In linear editing, each video clip is recorded after the previous clip onto a program reel. One problem with a linear system is the time it takes to reedit a segment or to insert a segment that is not the same duration as the original segment to be replaced.
Essentially, if you need to reedit a clip in the middle of a production, the entire program needs to be reassembled. The process is similar to creating a necklace with a string of beads.
If you wish to add beads to the middle of the necklace, you need to pull out all the beads, insert the new ones, and put the old beads back in the necklace, all the while being careful to keep everything in the same order.
In a nonlinear video system, you’re free to insert, remove, and freely edit. It’s almost as if you can magically pop the beads on the necklace wherever you’d like—as if the string didn’t exist.
Because the image is made up of digital pixels that can be transformed and replaced, digital video allows you to create numerous transitions and effects, which are not possible on a purely analog system.
To return to the necklace analogy, with a digital system, you can freely insert and replace beads, as well as change their color and shape at will.