Vela 2000-0600, Инструкция по установке и эксплуатации

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78 CineCast HD Version 2.6 Installation and User Manual
0047 Video/Audio Fade
0047 Video/Audio Fade
This command provides audio and video fading and switching capability. The
command offers video fade down from video source A to background then fade
up to video source B, with a maximum fade time of 255 frames. Video/Audio
switching is accomplished by setting the fade time to 0 or 1.
Fading and switching requires two CineCast HD decoders connected together via
the Vela media bus cable inside the chassis. Both decoders must be genlocked to
the same video source.
To implement an audio/video switch/fade two commands need to be sent:
• The first command needs to be the Fade Up and is sent to the current non-
decoding channel. This command should be sent as an inline command
triggering on GPI2. The Fade Down command will automatically set GPI2.
• The second command needs to be the Fade Down and is sent to the current
decoding channel.
Either of the two decoders can be the primary decoder. The primary decoder is the
decoder that has the audio and video cables attached and whose audio/video out-
put is being monitored. The other decoder is called the secondary decoder.
This command is also used to setup the audio routing on each decoder. To set
routing without performing a switch/fade simply clear the “Video Fade enable”
and “Audio Fade enable.”
Video Fade Enable
This bit must be set to enable video fading operation. When cleared, no video
switch or fade will occur.
Table 2-13.Video/Audio Fade Command Format