User Guide

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must be between 390-14648 kbps. When CBR is selected, the
data rate entered will be used all the time regardless of the
amount of information of the video. It may fluctuate at some
points but overall it will try to approximate the data rate
entered. When VBR is selected, the data rate will adjust itself
depending whether the material is simple or complex. It will
not exceed the data rate entered in the box.
I-frames only: By selecting this option, the MPEG encoder
will only compress the video to something called I-frames
(and not P or B frames). This makes the quality better but the
file size will be much larger. For most people, you should leave
this option unselected, as it disables an important part of
MPEG compression.
DVD-VR compliant: Select to automatically set the video
data rate to be compliant to DVD-VR specifications.
Two-pass encode: Select to analyzes the video stream
during the first pass to pre-determine the most appropriate
compression for each frame. This video encoding method
adjusts the bit rates more efficiently to create better,
smoother visual quality.
Audio settings
• Audio format: Select an audio coding format for DVD-Video.
MPEG video encoding format include audio encoding, which
use lossy information. Linear PCM (LPCM) is an uncompressed
audio format which is similar to CD audio, but with higher
sampling frequencies and quantisations. LPCM's maximum bit
rate is 6.144 Mb/s, which is much higher than MPEG-2 coding.
LPCM offers high quality but its drawback is that higher data
rates leave little bandwidth for video. AC3 audio is the digital
standard for compressed audio files. It is a new and unique
way of digitally compressing and decoding audio channels into
a very small space to produce high quality audio playback. It
covers eight different channel combinations ranging from
conventional monophonic or stereophonic sound up to a 6-
channel surround-type format.
• Audio type: Select from Mono, Stereo or Joint Stereo (often
used in MPEG compression).