How do you bring back color from black and white images and videos?

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How do you bring back color from black and white images and videos?

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They don’t “bring back” colours, those were never there to begin with, the photos are just recoloured in the most realistic way.

You don’t. Colorized black and white images are made by literally painting color over the image.

They don’t. When you look at a colour photograph, there are multiple things going on. Any particular surface has a colour hue or tone, this is what you think of as colours. Blue, red, yellow etc.

Those surfaces also have a luminosity or brightness. Some areas are light, others are dark and degrees in between those two. And of course, surfaces have other qualities like translucency and reflectivity.

A black and white photo captures most of those qualities so you have almost all of the information you need.

The only thing that’s missing is the colour itself. So what a colourist does is leave all of that luminosity information in place, that’s already present in the black and white photo. You just have to select colours and paint over surfaces while telling your software to keep the luminosity in place but add the colour hue.

So if you’re wearing jeans in a black and white picture, I can guess that they’re blue. So I paint a suitably blue colour over the top of those jeans while retaining the light and dark areas of the black and white image.

I could be wrong though, you could have been wearing red jeans instead of blue. For historical accuracy, a colorist should have some knowledge about his subject. But most of the time, the people who see the image are also missing that knowledge and won’t notice any mistakes.

We actually once requested a colorization of an old B&W photo.

For things with well known or obvious color, they just choose whatever but they actually had to ask us what color was grandma’s dress as there was no possible way to determine that from a BandW photo alone. At best they could know the “luminosity” of an object, not the hue.

There’s an article here about bringing back colour in videos: [https://www.bbc.co.uk/pressoffice/pressreleases/stories/2008/12_december/09/dadsarmy.shtml](https://www.bbc.co.uk/pressoffice/pressreleases/stories/2008/12_december/09/dadsarmy.shtml)

“James Insell, Preservation Specialist for the BBC Archive, found that many recordings had been created without the colour sub-carrier having been filtered out, and that the colour information was still embedded in the film as a pattern of fine dots – or “chroma dots”. ”

Basically some black and white film still has some colour information encoded. With images however it’s largely done with A.I. with some human help.

The artists that add colour often get it wrong. We do look back to the past and, as all we have seen is black and white photographs and faded paintings, we assume without thinking that the colours would have been muted. And so the colourists choose from a limited pallet, favouring browns and other muted, unsaturated colours.

This is incorrect. The past was a brilliant, colourful place. Early photographers experimented with colour photography, taking multiple pictures through different filters, and they captured brilliant colours. And the coloured objects that survive without fading, like ceramics and glass, are brilliantly coloured. So when recolouring a photograph, we should choose bright, exciting colours. And similarly, when you see a recoloured photograph, know that the colours you are seeing are almost certainly wrong.

The old way (as in just a few years ago) the best way was to just manually paint them back in based on a reference palette.

Since AI has gotten better over the past few years tough, it’s being used more and more to do the same job and having pretty good results.