Add none URL jpeg for map purposes

I want to create a heatmap of where animals have been in a small habitat. The area is not large enough to use a true ‘map’, and there is no URL of the image.

How can one show area usage when you are dealing with an area that is too small for an online map to depict? If I was able to insert a jpeg and highlight pixels as I would lat/long, I could work around this, but that is not an option currently…
Any other possible solutions?

We currently do not support this feature. We will pass this feature request to the concerned team for consideration in the roadmap.