The White Helmets program was put together in Turkey by James Le Mesurier, a former British army officer & military contractor. They are funded primarily by the US State Department through the USAID program & by the UK Foreign Office. The stated function of the White Helmets is rescue work but they also post a lot of pics & videos on social media, always with an anti-Assad message & often with high quality camera equipment.
CNN describes this video as an attempt to use the "mannequin challenge" meme that was popular at the time it was released to help the video go viral. (link)
John Pilger has described the White Helmets as a "terrorist affiliated group", "phony NATO shadow state construct, masquerading as a Humanitarian NGO". (link)