How to blend image in to background color

[Ofnuts]

(11-07-2019, 12:20 AM)getsignups Wrote:

(11-07-2019, 12:01 AM)akovia Wrote:

(11-06-2019, 07:19 PM)getsignups Wrote: I want to know how to blend the bottom of this image into the color of a black background.

I'm not sure if you meant a "black background" or not. 

Did you mean something like this?

Yes!
How did you do that?

In this very simple case (you hand is black), just create a white to black gradient, after setting the gradient tool to "Darken only" Since, expect at the bottom, the gradient is always lighter than the arm the arm is not changed.

In more complicated cases (random colors for arm and background), you would have to isolate the arm on a transparent layer, and create a gradient in a layer below it (or use the gradient tool in "Behind" mode).