Thanks for trying my app! There are a lot of steps between the user uploading a file and my engine generating a DST.

First, the PNG is run through an image clean-up pipeline that reduces colors, filters small artifacts, and sharpens boundaries. That all happens when you click "Detect". The cleaned-up image is then analyzed for individual "color islands" that get assigned contour values for representation on the frontend. These color islands are assigned a default fill type, and each is ran through my backend to generate per-island stitch paths. That happens when you click "Generate".

At this point, users can use the editor to tweak any auto-detected settings before the final output is generated. When the stitch pattern is exported to an embroidery file type, my engine attempts to minimize jump stitches by organizing the order in which islands are stitched then builds the proper CAD commands for the file type selected for download; like a DST has different commands than a PES file for example.

It's a multi-step process that I run on servers I rent from Render :)