When people first start playing with image editing software, they soon discover that they can invert the color of the image. They'll play around with this for awhile and then move on after their bit of fun.
Last year, I got it in my head that it would be neat to try inverting the brightness of an image without messing with the color. This turned out to be much more interesting than a normal inverted image.
Most everyone in this day and age has seen an image with its color inverted. These images look odd and, depending on the original image, sometimes really darn cool.
What an invert operation on an image actually does is flip the RGB values of each pixel. This has the effect of turning all colors to their opposites, and making pixels which were dark turn light and light turn dark.
If we want to invert the brightness of an image, all we have to do is invert the image and then correct the color. You can correct the color by shifting the hue of the image by 180 degrees. The results are fun to look at.
As you can see, in the image above, the colors stay the same. The grass is still green, the flowers are still red, and the path still brown. The difference is the brightness (obviously, since we inverted the brightness of the image).
The red flowers, which used to be pinkish red, are now dark red. The lush deep green of the grass has turned into a much brighter, almost florescent green. Even more stunning are the sun beams, which, after having the brightness inverted, now give the appearance of darkness breaking through the trees.
If you want to see more, check out the images below.