It's easy for a person to tell where the two interesting objects are in this picture but I found a way for the computer to do it as well.
Step 1: Make a new image where you look at each pixel in the original image and add up how far it's value is from it's neighbors. If it is exactly the same color as all it's neighbors that is a 0 if every surrounding pixel is exactly the opposite color that is a 255 (this means white in computer graphics).
This has the effect of making all contiguous areas of color or gradients solid black.
Step 2:Make a new picture where the new pixels are the average of the old pixels and their neighbors. Sort of a blur.
Step 4. Blur again but only keep pixels that are between 0 black and 128 grey, everything else is made white.
Now do the same thing again but only keep pixels that are between 0 black and 64 grey. All else stays white.
Now you should have a nice binary map of where the interesting parts of the original picture are with the noise removed.
So it's kind of interesting to see what this process does to normal pictures...