Beer Logo png Files Lose Transparency on Kegberry

I’m using keg bot on a raspberry pi2. I created png files for my beer logos in the hope of making my tap list look cleaner and get rid of the white space behind certain images. For some reason my png images are displaying with a black background instead of transparent background. Anyone know how I can fix this? If not, is it possible to make the background the same black as the logo? Thanks in advance!

PNGs create transparency in one of two ways. One of these methods employs the same approach used by GIFs, with a single color defined as transparent, and the other is to set an alpha channel . One of the advantages of PNG single-color transparency is that it doesn’t remove a color from the available palette. However, the alpha channel is a much smoother method, as it is far better at blending colors, and allows you to select different levels of transparency in specific regions. The transparent areas of the PNG will blend and adjust naturally to whatever is behind the image when the background of the page isn’t a solid white or black color.