Function VenitianBlinds for vctrans vapoursynth Plugin

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VenitianBlinds

The transition from Clip A to Clip B occurs by VenitianBlinds, or checkers or diamonds closing or opening. Frame should be at least 40 x 40 size

## trans.VenitianBlinds(clip, clipb clip[, float overlap = 1.0 ][, int style = 1][, int slatwidth = 1/16th frame smaller dimension][, int open = 1 )

Parameter description:
clip : A clip. Constant format. at least 4o x 40 size
clipb : B clip. Must have identical format of A clip
overlap : transition time length in seconds. Floating point. Must correspond to at least 8 frames. A longer duration is preferable.
style : 1.vertical slats 2. horizontal 3 diamonds 4 checkers
slatwidth : 8 to 1/8th of frame smaller dimension
open : slats of A open to reveal B or slats of B close on A
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