Windows
On Windows: trace a scanned drawing in Inkscape
- Open the JPG in Inkscape (free) with File > Open and accept the import dialog.
- Select the image and open Path > Trace Bitmap.
- Choose Single scan with Brightness cutoff and move the threshold until the strokes are solid and the paper is gone; the preview updates as you change it.
- Raise Speckles to ignore dust and JPEG noise, click Apply, delete the original image, and save as Plain SVG.