Digital Audio Formats - Creative Sound Blaster Audigy 2 ZS User Manual

Digital Audio
Formats
DV type 2
This is a form of DV often found when stored as an AVI file on a PC in which the
video and audio streams are separated from each other. The value of this form is
that it is compatible with a wide variety of video software applications. Use this
form if you are capturing DV to make a DVD.
MPEG1
Developed by the Motion Picture Experts Group. Generally lower visual quality than
MPEG2, particularly for action scenes. Doesn't store interlaced video. Used for
Video CDs (VCD) at 1.0 Mbps which provides VHS level visual quality at best.
MPEG2
Used for DVD and super VCD (SVCD). Allows higher bitrates than MPEG1, resulting
in higher visual quality. MPEG2 offers improved encoding techniques compared to
MPEG1 and user-selectable bitrates for control of space and visual quality,
including VBR – Variable Bit Rate.
MPEG is a lossy compression format – a signal that has been compressed then
decompressed is not an exact duplicate of the original. It uses perceptual coding to
eliminate data that cannot be perceived by human senses. MPEG2 also uses
predictive technologies to interpret information that does not change between
frames and saves space by storing the information only once. Such inter-frame
similarities, for example a stationary house, are common in video. In addition,
MPEG2 allows adaptive compression where bandwidth can be shared between
portions of video segments to flexibly balance and control the overall bitrate.
The digital video in your video project will be interspersed with digital audio (your
"soundtrack") that has its own forms of compression and will take up space
(although much less than the video). For a DVD project, during the output phase,
the video and audio will be burned to your DVD in a format that is allowed by the
DVD standard, and thus compatible with your consumer DVD player.
Technology Glossary A-8