-File / Import (Advanced) / cardiogram.jpg
-Coordinate System count=3
-Ok
-View / Background / Show Original Image
-(With '1' appearing in the Coordinate System toolbar)
-Settings / Segment Fill / PointSeparation=5
-Select Digitize Axis (3 red points)
-Enter 3 axis points for one curve
-Select Digitize Segment (green line)
-Click on the first curve in various places
-(Repeat previous step with '2' appearing in the Coordinate System toolbar)
-(Repeat previous step with '3' appearing in the Coordinate System toolbar)
-File / Save
-(With '1' appearing in the Coordinate System Toolbar)
-File / Export / <filename1>
-(Repeat previous step with '2' appearing in the Coordinate System toolbar)
-(Repeat previous step with '3' appearing in the Coordinate System toolbar)