Algorithm for text page up/down orientation determination

We present an algorithm that operates on a bit-mapped text pattern array to determine the up/down orientation of the page, that is, whether the page i s upright or inverted. The algorithm exploits an up/down asymmetry of passa ges of text composed of roman letters and arabic numerals. A computer progr am that implements the algorithm is listed. Experimental results from elect ronically received facsimile (fax) pages verify the effectiveness of the al gorithm. (C) 2000 Elsevier Science B.V. All rights reserved.