Grass Valley Imagestore 750 v.3.0.1 - Manual (Page 57)

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Imagestore 750
User Manual
One situation where masking an external fill and key signal is useful is when output from an
external graphics device must be split between two keying layers in different regions of
screen area.
DVE (for Program and Preview)
The Imagestore 750 digital video effects (DVE) options provide visual effects giving comprehen-
sive video image manipulation, including picture-in-picture squeeze transitions over a
background. The main DVE features include:
• Single or dual 2D (rectangular) squeezes over a background.
• Independent control of DVE squeezes on the program and preview buses.
• Cropping and masking of squeezes, including soft edges and colored borders.
• Adjustable layering of dual DVEs, to bring new content to the front.
• Editor for creating and modifying DVE sequences to move between different squeeze posi-
tions.
• Up to 97 different DVE sequences stored on the Imagestore 750.
• Compensating video delays, post-A/B-mix on program and preview.
The following DVE options are available for the Imagestore 750:
IS-750-DVE Enables a single DVE window on PGM and PVW.
IS-750-DVE-DUAL Enabled two DVE windows on PGM and PVW.
The DVE processors provide digital video effects on any of the input video streams or A/B mixer
output. Digital video effects are suitable for picture-in-picture applications such as over the
shoulder news transitions, as well as squeezes for credits, news flashes, sports results, and
schedules.
You can create and manage DVE sequences using the DVE Editor (available on the Media
Conversion Suite CD). Using the DVE editor software, you can upload up to 97 sequences onto
the Imagestore 750 for later playback.
The DVE delay is exactly 2 interlaced fields or 2 progressive frames. For 59.94 Hz standards, the
delay is 2 / 59.94 s and for 50 Hz, standards the delay is 2 / 50 s. Any non-active picture data in the
DVE input stream is also delayed while the video is resized.
Note: It is important for video and audio (including metadata) to maintain a constant and
unchanging delay through the Imagestore 750. To compensate for any potential DVE
processing, matching delays must be applied to the background video (after the A/B mix), and
to the audio/metadata paths defined within the audio engine.
You can set the DVE mode to ‘enabled’ or ‘disabled’ for the program and preview buses indepen-
dently. When the DVE is enabled, DVE picture insertion takes place with the DVE window(s)
being keyed at the position defined by the DVE configuration. When the DVE is disabled, DVE
picture insertion is taken out of circuit to reveal the background video coming from the A/B
mixer. In both cases, a DVE delay is experienced at the Imagestore 750’s output.
The DVE configuration menu option of the Imagestore 750’s front panel ( Operate > DVE
Config ) and the Imagestore 750 Configurator allows the position of the DVE picture insertion
within the video path to be one of the following.
• DVE inserted before all keyers