The contour is the outline of a pattern piece. Depending on the pattern it is the cutting edge or the seam line, and every other marking sits inside it.
PatternScan Pro detects the outline of the photographed piece and stores it as one closed curve with control points. In the seam allowance panel you say whether that line is the seam line or the cutting edge, and the file then carries both lines.

Digitize sewing patterns without tracing.
Test PatternScan Pro free for 14 days with the full feature set. You need your smartphone, a printer and one pattern you always wanted digital.