Is there any default tool in OSX by which to add text (such as subtitle) to a video? I would like to add a notification to a video at some particular time period that "Mistake  Lorem in this".

Does OSX have any default video tool (simple) to add any type of text (subtitle ok too) to the video?
iMovie may work for you.

Import your Movie and then.

1,  Select the Titles in the Content library to pick Title theme

2, Drag the Subtitle Theme down to the movie strip.

3, Adjust the Subtitle time line to where you want it and duration.

4, Write you text in the text field.

5, Set your text style.





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