Methods and apparatus for determining and/or modifying image orientation

摘要

Methods and apparatus for processing one or more images, e.g., images representing pages including text, to detect and in some instances correct the orientation of the page. In some embodiments the methods and apparatus for processing image data comprise generating a histogram of foreground pixel counts corresponding to a current line of text of the image being processed with the foreground pixel counts corresponding to different rows of pixels corresponding to the current line of text and identifying based on statistical analysis of the generated histogram whether the current page of text is oriented in an inverted or non-inverted position. In some embodiments analysis is performed on multiple lines of text with cumulative statistics being used in to determine the orientation of the page. In some embodiments, a page whose orientation is determined to be upside down is re-oriented to be right-side up.

主权项

1. A method of processing a page in the form of an image, said page including lines of text, the method comprising:
generating a histogram of foreground pixel counts corresponding to a current line of text of said page being processed, said foreground pixel counts corresponding to different rows of pixels corresponding to said current line of text; identifying a first peak and a second peak in said histogram, said first peak corresponding to a row of pixels above said second peak; determining if said page is inverted or non-inverted based on a difference between a first count of foreground pixels in a first portion of said current line of text and a second count of foreground pixels in a second portion of said current line of text, said first portion being located in said line of text above said first peak, said second portion being located in said line of text below said second peak.