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There are no rules governing the color codes, so while the use is arbitrary, there is a pattern to this.
Red: Usually used in areas that may be more prone to accidents and require attention. Intersections w/o signals, sudden curves, lanes where buses makes stops... Some places use it to indicated no-parking zones. They also provide extra grip, according to some sites.
Green: Usually used to indicate school zones. A lot of times, just the outside is painted green to indicate areas dedicated for pedestrians on roads that don't have dedicated sidewalks (link).
Blue: Blue is often used to indicate bicycle lanes, but can also be used to indicated specific lanes like a right turn lane. You'll see blue lines or dotted lines as well.
I've never seen roads that are yellow and I can't fine any information on yellow roads, so I don't believe these exists in Japan. And I've never seen red like the color of your pic! Maybe that's how the red looks like when it's freshly painted...
I found a lot of the information I listed here.