Ulead 1.0 - Manual (Page 81)

SpruceUp User’s Guide 4—9
Video Assets
Introduction
SpruceUp requires the video movies to be a DVD compliant MPEG format. There are a
number of methods for transcoding video from its current format to MPEG.
For analog sources, you need a hardware video capture card to digitize the video.
Depending on the card's output format, you may then need a transcoder to convert it into
MPEG.
For sources that are already digital, such as QuickTime, DV and AVI files, you will typically
use a software transcoder to convert into MPEG.
The quality of the MPEG encoding is what determines the quality of the title. It is well worth
putting some effort into getting the best MPEG encoding environment possible.
General Quality Issues
Start at the Source
Get the best MPEG encoding environment you can. For example, start with the best quality
source material you can – a digital source is the best. Of the analog formats, component is
preferred, followed by S-Video (Y/C), and as a last resort, composite. See the Video Basics
topic for more information.
Noisy Video
Since a large portion of MPEG’s compression power depends on its ability to locate areas of
the image that do not change between successive frames, noisy video can be a real
problem. While the actual video may be identical between two frames, if there is a noise
spot on one and not on the other, it is detected as a change in video requiring more bits to
encode. Lots of noise causes poor encodes, with the encoding resources being tied up trying
to faithfully reproduce the noise!
Transcoding Artifacts
Every time video is transcoded from one format to another, for example from analog to
digital, or QuickTime to MPEG-2, artifacts are introduced into it. How noticeable they are
depends on the quality of the transcoding device and the content. While transcoding cannot
be avoided, its affects can be minimized. Use the highest quality equipment and software
you can, and choose products that work well together, supporting each other's formats.
What is MPEG?
MPEG (Motion Picture Experts Group) is a family of video and audio compression formats
that make possible high quality titles on DVD and CD mediums. There are a wide variety of
MPEG types and settings – use care to select those that are DVD compliant as explained in
the following and covered in the MPEG Settings Summary topic. SpruceUp imports MPEG
assets created on a wide variety of third party products. The following is to provide an
overview of MPEG in general, with details relating specifically to SpruceUp.
Elementary and Multiplexed MPEG Files
There are two types of MPEG file structures SpruceUp supports: Elementary and
Multiplexed.
Elementary files contain only one stream of data, either the video or the audio. Elementary
MPEG-2 video files typically have a “.vbs” or “.m2v” extension; MPEG-1 files have a “.m1v”
extension. Corresponding MPEG-1 layer 2 audio files have an identical name, but with a
“.abs” or “.m1a” extension. The DVD specification also supports AC-3 Dolby® Digital audio
files, which typically have a “.ac3” extension. For uncompressed audio, files will have