To easily detect the line direction of a character string and decide whether the character string is written longitudinally or laterally without previously fixing a way of writing the character string and the line direction of the character string.

A handwriting inputted on a coordinate input surface is detected by a handwriting input part 11 as a time series of two-dimensional coordinates and stored in a storage part 12. A base line detection part 13 detects a base line from strokes constituting the handwriting (indicated by the coordinate series) stored in the storage part 12. A character string information extraction part 14 detects the line direction of the character string in the handwriting from the base line and decides whether the character string is written longitudinally or laterally on the basis of the position relation between the detected base line and the character string in the handwriting according to the restrictions of the predetermined position relation between the character string and base line. A line correction part 15 rotates the character string in the handwriting according to the line direction detection result and longitudinal/lateral writing decision result of the character string to enable a recognizing process by a character recognition part 16.