In this article you will learn how to set up the workflow and how to optimise spotting rules when subtitling vertical video.

By default, the subtitling spotting rules used by Limecraft Flow are optimised for creating subtitles on horizontal videos. In this article you will learn how to optimise the subtitling spotting rules for subtitling so that they fit on vertical videos. 

vertical video is a video created either by a camera or computer that is intended for viewing in portrait mode, producing an image that is taller than it is wide. Because of this tall image, you need to adjust the settings to ensure a good readability. You need to have less characters on one line and have more lines visible on the screen. 

Note that any changes to these settings apply to the entire production. We therefore recommend using a dedicated production for vertical videos only. Also note that the cell resolution settings discussed below are only visible when you export subtitles in EBU-TT-D format.

Once you’ve successfully set up a production for vertical videos and you’ve uploaded material, you can go ahead and change the settings as follows.

  1. Regions

First of all, you need to change the region where the subtitles are shown. Go to your Production Settings and then to the Subtitle Editor. 

There you’ll see “Bottom Region” and “Top Region”. We recommend using 90% width and 30-32% height (for both) and to try if these fit your content.


  1. Characters on a line and number of lines

In the same section of the settings (the Subtitle Editor), you find the spotting rules. We recommend adjusting these as follows::

  • The amount of characters on a line: at most 25 characters (hard limit 29 characters)

  • The number of lines: 3 lines (hard limit 4 lines) 

  1. Cell resolution

If you scroll down in the same settings section, you find the Advanced settings where you can adjust the cell resolution.

The cell resolution defines a virtual 2D grid of cells over the video canvas. “Cell Resolution X” defines the number of columns in this grid, and Cell Resolution Y defines the number of rows in this grid. As font size and line height are based on the cell height, cell Resolution Y can be used to influence the subtitle font size. A more thorough explanation can be found here: .

For a vertical video, we recommend changing the Y cell resolution from 15 to 27.