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Closed Caption/Subtitle support


I've implemented the closed caption support using WEBVTT format as the source for the subtitles. These display however, the positioning of the captions are inconsistent where some words appear on single lines and the text is right aligned.

I appreciate that the Roku parser doesn't recognise many html tags, but should it not obey the positioning and alignment commands?

Any help would be much appreciated.

Here is an example of the vtt file..


NOTE: MatID = 56966001001001   Title = *************                
NOTE Created by .sng webVTT Encoder module WriteVTT v2016_10_28-1

00:00:02.000 --> 00:00:07.000 line:77%  position:50% align:middle
<c.white>This programme contains strong</c>
<c.white>language and adult humour.</c>

00:00:32.560 --> 00:00:35.960 line:77%  position:50% align:middle
<>Tonight on **********</c>

00:00:36.000 --> 00:00:38.720 line:77%  position:50% align:middle
<>Playing the numbers game,</c>
<>it's Pete James.</c>
3 Replies
Roku Employee
Roku Employee

Re: Closed Caption/Subtitle support

The WebVTT parser does handle position, line, and align directives and try to use them in the painter code that draws those subtitles.  However, I think you've uncovered a bug in the interaction between the alignment and position values.  It looks like we're using the line and position values to set the top-left corner of the text area, and then centering the text in the box that's left there on the right side of the screen.

I'll see if we can get this fixed for a future release.  In the meantime, try removing the position tags and see if that gives you centered text like you want.

Re: Closed Caption/Subtitle support

Thanks for the response.

Is there any ETA for the fix (roughly)?
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Level 8

Re: Closed Caption/Subtitle support

they are still not readable . they are SEE THRU

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