Set default main background colour to #FFFFFF

[Popolechien]

The current setting is Default to main color of profile image, which more often than not gives a weird shade of pink (see, e.g., here, where the original banner is mostly... blue).

Youtube has a white backgroud, I see no reason to depart from it.

[kelson42]

I recommend to be careful here. This has been done to ensure that at a first look content could be differentiated. If at the end the color is not OK because weird, or always giving a similar color. Then maybe the solution is to have a better algorithm.

[benoit74]

Algorithms on how to extract "nice" color from an image are then welcomed 😉

Do we want to have a palette of let's say 50 approved colors and choose the closest one?

[Popolechien]

Well Youtube has a white background, why would we want to depart from canon?

This has been done to ensure that at a first look content could be differentiated

On a side note, I do not understand this remark nor do I remember the discussion that led to this decision (but then I rarely do 😁 ).

[benoit74]

On my side, I tend to prefer the fact that background is not totally white since it allows to differentiate ZIMs which I find quite cool. And I'm not that bothered by the automatically chosen color.

But I'm also not concerned if we choose to use white (or black once we will support dark mode ^^) everywhere by default.

I'm more embarrassed by the fact that we begin to set #FFFFFF in every youtube recipe of the farm.

[kelson42]

To me the problem behind this issue is that the algorithm which computes the baground color is wrong. Why not just do something better? I would first probably take the banner image a seed for color and then look to the algo. I have the feeling it does some kind of average and probably it should better take the dominant part in the color spectrum and then reduce saturation (which seems to be already the case).

[benoit74]

Current algorithm is here: https://github.com/openzim/python-scraperlib/blob/335d5271e106b374f1aca871d19557ff2c81582d/src/zimscraperlib/image/probing.py#L18-L49