Don’t They Know It’s Christmas Time?

If you are not seeing the YouTube video after the 7 photographs of flowers blooming unseasonally in our garden, here is the link: https://youtu.be/xjG_VB-la7o

 

Colourisation

I have been playing with colourisation tools. No, not paints and crayons, but software that colours black and white photographs automatically. It uses “artificial intelligence” and “deep learning” through “electronic neural networks” “trained” on millions of colour photographs. 

“Wow! Fantastic!” one might say, but having once worked on the periphery of a team of artificial intelligence researchers, I remain sceptical. I used to go from “Wow! Fantastic!” to “Is that all it is?” in the space of a forty-five minute seminar. 

Carried out manually, colourisation is a skilled, time-consuming, labour-intensive process. As well as expertise in tools such as Photoshop and a level of colour-sense I simply do not possess, it can also involve historical research to indicate what colours the photographer actually saw. Experts can spend a month on just one picture. 

So, it would be wonderful to be able to colour photographs automatically. I found these free resources (it may not be a complete list): 

• Algorithmia: https://demos.algorithmia.com/colorize-photos
  
• MyHeritage: https://blog.myheritage.com/2020/02/colorize-your-black-and-white-photos-automatically-with-myheritage-in-color/
• Photomyne: https://photomyne.com/colorize-app
• Pixbim: https://pixbim.com/colorsurprise-ai-pixbim  
• Playback.fm: https://playback.fm/colorize-photo

With four of them you upload a black and white photograph to the web site and then download the colourised version. Pixbim is different in that you download and install a trial version on your computer and carry out the colourisation locally.

Are they any good? I tried them out on black and white photographs from earlier blog posts.

Bridlington c1929 - colourised by MyHeritage

Uncle Jimmy’s Bullnose Morris c1929 - colourised by photomyne

Bridlington 1955 - colourised by MyHeritage

Grandma 1963 - colourised by playback.fm

In general, the different tools gave different results and no one was consistently better than the others. I tried to pick the best result in each case but you might have chosen otherwise as I possess a different distribution of cone cells from most people. My choices might be a bit green, or a bit pink, I don’t know, I wouldn’t be able to tell. However, there were some truly awful ones, one of which seems to think I was wearing pissy underpants.

 

Colourised by Pixbim

Colourised by Algorithmia

Colourised by photomyne

Colourised by Algorithmia

Of course, we do not know what the colours really were, although I do feel fairly confident that the Bullnose Morris was not brandy coloured, and know for a fact that the Pratts petrol can on the running board was spruce green (#2e4a41), which none of them got right.

 

One test of colour accuracy would be to re-colourise an existing colour image after first reducing it to monochrome. MyHeritage does not seem too bad to me on the Abbey Road cover (I wonder if this was one of the pictures it was trained on), but they all struggled with scenery.   

The Beatles Abbey Road (left) recolourised from monochrome by MyHeritage (right)

Spring Polyanthus 2020 (left) recolourised from monochrome by MyHeritage (right)

Glacial deposits in Glen Roy 2020 (left) recolourised from monochrome by Pixbim (right)

Johnson and Trump (left) recolourised from monochrome by Pixbim (right)

It is pretty impressive that black and white photographs can be coloured automatically at all, even though the colours are by no means accurate and not a patch on the original. 

Colourisation does seem to add something, particularly depth. Perhaps it works better with cine film, as in Peter Jackson‘s painstakingly restored First World War films (They Shall Not Grow Old) in which the moving faces of young soldiers, poignantly grinning amidst the mud of the trenches, become living people like us. 

I am not as sceptical as I was, but find myself thinking that with photographs it is probably better to stick with the original black and white. 

It would be interesting to see your efforts (irrespective of whether you call it colourisation, colourization, colorization or colorisation). 

FURTHER NOTES

I usually preferred MyHeritage, photomyne or playback.fm, but some reviews speak highly of Pixbim, possibly because it allows control over the colours (see below).

The colourised photographs are not always the same size as you started with.

There are other limitations too. MyHeritage permits a limited number of free colourisations (I’m not sure what it is, maybe 10, but me, Mickey Mouse and Billy Liar have all used our quotas) before asking for a minimum £50 subscription to its genealogy services. One should also be aware that the uploaded photographs are retained and may be visible to others, but can be deleted.

Pixbim (the one you download and install) allows you to adjust various processing parameters, such as colour intensity and colour temperature (from reddish to blueish), and provides a brush tool for correcting incorrect colours, whereas with all the others you get what you are given. However, the trial version of Pixbim comes with only a 7-day licence after which it costs £40. Also, unless you buy it, the colourised photographs have “Trial Version” printed all over them, but you can get round this using PrintScreen to capture a smaller version of the coloured image.

I also found mention of two other tools: Colourise SG which now appears to have been withdrawn, and Colorize Photo (www.colorizephoto.com) which assists you in carrying out the colourisation yourself, which I have not tried.