Joint-portion processing device for image data for use in an image processing apparatus

A method for joining together a plurality of partial document data in an image processing apparatus, comprising the steps of:

• reading an original document by scanning a plurality of partial images in succession, the original document being defined as a composite of the partial images;
• storing the partial images as respective partial document data in a memory;
• recognizing adjoining edges of the partial document data stored in the memory by extracting features along the edges of the partial images and comparing the features between different partial images;
• extracting image data that lie in a direction orthogonal to the adjoining edges of the partial document data;
• and
• positioning the respective partial document data in accordance with the extracted image data that lie in a direction orthogonal to the adjoining edges.

An image processing apparatus for automatically combining input portions of an original document, comprising:

• input means for scanning a plurality of portions of an original document, each of approximately equal shape and including a number of edges, the original document in its entirety not being scannable in a single scan by the input means;
• a memory for storing each of the plurality of scanned portions as partial image data portions;
• feature extraction means for calculating an amount of stored data corresponding to a predetermined area of each stored partial image data portion, for extracting features from the predetermined area, and for comparing the calculated amounts of stored data of each stored partial image data portion to other stored partial image data portions;
• joint portion processing means for comparing extracted features of predetermined areas of partial image data portions containing approximately equal calculated amounts of stored data, for extracting data orthogonal to edges of each of the partial image data portions of approximately equal calculated amounts of stored data, and for aligning the extracted data of the partial image data portions to thereby combine the stored partial image data portions in a form representative of the original document.