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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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The grid is superimposed on the video player to help setting or determining the exact text position on the screen. You can turn it off using Settings → Toggle Video Grid.
Tool Panel
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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 |
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