ADS Technologies USBAV-708 INSTANT VIDEOMPX, User Manual

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1-Pas
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1-Pass, Quality-based mode is not explicitly unsupported by DivX Certified
devices, however the
Video Buffer Verifier is disabled in this mode and there
is no guarantee that the video stream produced will not exceed the
capabilities of the certified device.
When 1-Pass, Quality-based mode is enabled any Video Buffer Verifier CLI
parameters are disregarded.
You cannot set a bitrate for 1-Pass, Quality-based mode.
MV re-use is not permitted under 1-Pass, Quality-based mode.
Use 1-Pass, Quality-based mode when capturing from a live source and
attempting to maintain a consistent quality throughout the video without
consideration of the resulting file size.
It is impossible to control or predict the bitrate or file size under 1-Pass,
Quality-based mode, other than to know that encoding the same source at
higher quantizer will produce smaller files and vice versa.
1-Pass, Quality-based mode is particularly useful for capture when you intend
to later re-compress a video using Multipass mode. In fact, 1-Pass, Quality-
based mode can be used in place of
Multipass, 1st pass mode so long as
Write log file is enabled. In this way it is possible to capture in 1-Pass,
Quality-based mode and proceed directly to Multipass, nth pass . When
making use of this technique take care to avoid overwriting your 1st pass file
containing the captured video with the
Multi-pass, nth pass output
accidentally.
Under the same principle, 1-Pass, Quality-based mode allows you to perform
XVID-like Multipass encoding. XVID performs its first pass with Q=2.
Bitrate mode is one of:
-bv1 <bitrate> 1-Pass
-b1q <quantizer> 1-Pass, quality-based
-bvn1 <bitrate> Multipass, 1st pass
-bvnn <bitrate> Multipass, nth pass
Bitrate is an integer value between 0 and 16,000 specifying the number of
kilobits per second.
Quantizer is floating point value between 1.0 and 31.0 specifying the fixed
quantizer to be used.