Satellites provide so much data, that it became a worldwide research area on how to interpret the data and combine the data from different sources (sometimes called data fusion).

One approach I have explored is called "panchromatic sharpenning". It is used when you have two images: one is of high resolution, but only in gray scale: the color intensity. The other one is full colored (all three RGB chanels), but a very low resolution. So, can we fuse these data to get one, sharp and color, image?

Yes, we can! Here is how: Have a high-resolution, gray-scale (intensity) image:

Have a low-resolution, color image:

Complete the following steps: Resize the color image to the size of the gray one, convert it from RGB to HSI color space, and replace the intensity channel with the gray image. Now convert back to RGB space, and here you go!

Cool, isn't it? It is important, though, that both images are perfectly registred. If not, see the slight discoloring (bluish) in the right low corner?