ADS Technologies USBAV-708 INSTANT VIDEOMPX, Руководство пользователя

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The video buffer verifier prevents the encoder
exceeding the ability of a target system to read
and buffer the video stream as to prevent
pauses in playback.
QUICK GUIDE
Video buffer verifier
Each DivX Certified Profile has specific VBV parameters associated with it
that ensure playback performance on DivX Certified devices. Although it is
possible to alter the VBV parameters in a way that would not negatively
impact playback performance, changing the VBV parameters is not
recommended except by experienced users with specific reasons for doing
so.
The default VBV parameters are:
The default initial occupancy is 75% of the buffer.
Profile Bitrate Buffer Initial occupancy
Handheld 128000 262144 196608
Portable 768000 1048576 786432
Home theatre 4000000 3145728 2359296
High-definition 8000000 6291456 4718592
Using the video buffer verifier it is possible to create MPEG4 video streams
suitable for streaming, even though DivX Pro does not include a streaming
server itself.
By careful configuration of the VBV parameters you may be able to improve
playback on older MPEG4 compatible DVD players that have not been
certified by DivX Networks.
Although the initial occupancy is always obeyed by the video buffer verifier
and is useful particularly at the beginning of an encoding session, it may not
always be respected by a decoder.