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 | Captions style | Allows to set CC style, such as pop-on, roll-up or paint-on |
 | Split block | Splits current caption into two parts to allow individual positioning for each part |
 | Merge block | Merges current split caption into one |
Video Grid
Line 21 and digital closed captions are typically transmitted in mono-spaced, fixed width and height, font.
By default in CC mode, a video grid will be enabled on the player window. The video grid will allow for precise caption positioning and preview in the player.
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Validation Rules
In addition to open subtitles validation checks, Closed Captions mode also enforces captions timing overrun. Timing overrun error means that the caption does not have enough build-up time.
Build-up time, or time to process, represents the number of frames needed to display (transmit) the caption text and the control codes. If it is less, the captions won't be displayed correctly.
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