1. A method for producing an accurate outline of a selected image portion in a picture, said method comprising manually tracing the outline of the image portion to produce outline coordinate data approximately representing the image outline, storing the approximate coordinate data produced by the manual tracing, automatically scanning overlapping image outline portions with an image sensor, and producing accurate image outline coordinate data, wherein the accurate image outline coordinate data is produced by the steps of moving the receiving surface of the image sensor to selected approximate coordinate data positions as determined by the manual tracing, projecting the image outline area surrounding each approximate coordinate data position onto the receiving surface of the image sensor, comparing the signal level received from each approximate coordinate data position with the average signal level received from the area surrounding that coordinate data position, and assigning accurate image outline coordinate data based on differences between the coordinate data position signal level and the average signal level of the surrounding area.