How do they do this?

RobynHood said:

https://cdn.jwplayer.com/previews/lzQ8Itla
Taken from https://www.independent.co.uk/tv/lifestyle/sleep-weight-loss-dementia-michael-mosley-b2496075.html#:~:text=Professor Esra Tasali at the,often linked to weight gain.

I am not brilliant with video. Does anyone know how this was done?

The bit I am interested in is the images of the wav file playing on the video.

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