Switching dolby e signals, Advanced audio, Video a/b mixing – Grass Valley Imagestore 750 v.3.0.1 User Manual
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Imagestore 750
User Manual
The Imagestore 750 supports the following Easyplay audio clip file formats:
All audio clips must be generated at 48
kHz (48,000 samples per second). You can generate WAV
files with 16 bits or 24 bits per sample. WAV files of 24 bits are preferred.
Switching Dolby E Signals
When it is operating in a progressive video standard (720p at 50 or 59.94
Hz) and switching
Dolby E signals, the Imagestore 750 must be given an interlaced reference input
—
such as 1080i
tri-level or SD bi-level analog reference
—
and the Dolby E data must be aligned to this refer-
ence. That is because Dolby E data are locked to the interlaced frame.
•
720p at 59.94
Hz = 59.94
Hz frame rate
•
1080i at 59.94
Hz = 29.97
Hz frame rate
This requirement applies to all Imagestore 750s that receive Dolby audio data, regardless of
whether any Dolby decode/encode options are enabled. Imagestore 750s without enabled
Dolby options can cut-switch between Dolby data streams, with the transition occurring at the
mid-point of an A/B mix.
Advanced Audio
, discusses advanced audio features available in the Imagestore 750.
Please reference these sections:
•
•
•
•
•
•
Video A/B Mixing
The Imagestore 750’s video A/B mixer is fed by any of its input sources or by an external router.
The mixer’s output provides the background video source for the PGM keyers. The mixer can be
dynamically configured either to cut or to fade the video. The Imagestore 750 supports cross-
fades, cut-fades, fade-cuts, V-fades and U-fades over variable durations, with V-fades transi-
tioning through a predefined color field. You can define the profile of each fade type.
You can configure the audio mix to follow the video mix automatically. Choose Setup >
Audio Setup > Follow Video > A/B Mix
at the Imagestore 750’s front panel. Alter-
natively, you can configure the audio mix to be completely independent of the video.
.wav
Multi-channel WAV files. (This is the preferred format.)
.oxw
2-channel clips created with Audio Builder (available on the MCS CD).
.oxe
Multi-channel Imagestore 750 audio file created with Audio Builder.