Spring at the Gulf of Bothnia

The spring is coming to Finland and meltwater is running through rivers into the Baltic Sea. The exceptionally cloudfree Landsat 8 imagery from 2016-04-14 shows beautiful features in the Gulf of Bothnia near the Finnish coastline. Some remaining ice cover still exists at the Bothnian Bay, but algae has already begun to form at the Archipelago Sea.

 

Below is a zoomable natural color composite of the Landsat 8-imagery in 30 m resolution:


Algae blooms from satellite imagery (Landsat 8)

I’ve been lately tinkering with Libra, a free service to browse and download satellite imagery from Landsat 8 satellite.

This is an image from Landsat 8 satellite (2014-07-23) showing massive algal blooms at Archipelago Sea.

landsat_2014_07_23_web

You really should check this huge high resolution image to get a sense of scale.

Those tiny dots are large ships cutting through the algae mush:

landsat_closeup_1

Reconstructing photos

This is an experiment on reconstructing a picture using the chunks of another picture. That is, take one picture (the brush picture), divide it into a reasonable amount of rectangular “chunks”, and then try to construct another picture (the target picture) by reordering the “chunks” of the first brush picture. Sounds trivial, but the real art is in how to do the reordering.

For those mathematically oriented, this is a problem of finding the permutation of the array of “chunks” which minimizes the difference between the permutation and the target image according to some metric.

Continue reading Reconstructing photos