Legacy ImageMagick Discussions Archive

I was looking at this website which has watercolour style maps:

maps.stamen.com/watercolor

Here is an example of New York



I note that the website relies on openstreetmap for it's initial map images, which it then converts into watercolor maps. I have played about with imageMagick, but can't seem to come up with settings that would transform normal map images into this watercolour effect. Does anyone have any suggestions that may work?

In the example, the water is replaced by a tiled image. We can see the repeated pattern.

Where does the pattern come from? I would do it with fractal noise (aka Perlin noise). See Fractal noise . But I expect a simpler method, probably based on plasma, could work.

snibgo wrote: ↑2019-07-19T05:59:19-07:00 In the example, the water is replaced by a tiled image. We can see the repeated pattern.

Where does the pattern come from? I would do it with fractal noise (aka Perlin noise). See Fractal noise . But I expect a simpler method, probably based on plasma, could work.

What about the land? Did you have a look at the website to see the paint style they use for any location:

http://maps.stamen.com/watercolor/#12/37.7706/-122.3782

I was kind of hoping there would be a simple command in imagemagick that would achieve a similar paint effect. It does not have to be an exact match, just a similar effect.

I suspect the effect shown at http://maps.stamen.com/watercolor/#12/37.7706/-122.3782 of water and land is from scanned watercolor images.

snibgo wrote: ↑2019-07-19T08:48:55-07:00 I suspect the effect shown at http://maps.stamen.com/watercolor/#12/37.7706/-122.3782 of water and land is from scanned watercolor images.

But how would they go about applying it to data from open street map? If you read their license it says they use open street map.

Is there no simple way of achieving something like this in imagemagick? there are various pieces of software that can turn photographs into a painting effect, but that does not work so well with these map images.

Open Street Map (OSM) data is available in vector format. A scanned watercolour image is raster data, ie pixels. Raster data can be used to fill in areas of a vector image.

I don't use OSM as a developer. Perhaps it is available as SVG. If so, you have the choice of (a) tweaking the SVG to include the raster watercolour images, or (b) rasterizing the SVG using solid colours for land and water, then changing those solid colours to the watercolour images.

Please show the same map before the watercolor effect. Search Google for "photoshop watercolor effect tutorial". There are plenty of links to look at. If you can do what you want in Photoshop, then it probably can be implemented in Imagemagick, if it does not involve artificial intelligence - deep learning with training.