RR_03_02

marked as common elements and classified as
background elements.
3. Results and Discussion:
We have tested our technique on 7 different
documents ranging from marketing brochures, interior
design books, a catalogue, and a weekly journal, for total
of 130 pages. As shown in table I, among all the pages,
there are four false negative cases where the header,
footer or the pattern is slightly different from ones on the
rest of the pages in the document. There are three false
positive cases, where one pattern belonging to the
foreground content is accidentally repeated on three
different pages. Figure I shows examples of background
pattern recognition and extraction from a catalogue.
Figure la shows the original pages from the document,
and figure I b shows the extracted background pattern
from the document.
We have also tested this algorithm on documents that
are a collection of tickets for different tourist attractions
and supermarket weekly advertisements. Because of the
repetitive text patterns in the content, text elements that
belong to content were mistakenly classified as
background pattern elements. For those types of
document, further restriction of the elements type may be
required.
Documents Total number Number of false negative pages(missing Number of false positive pages(picking
of pages Background elements) elements in the foreground content)
Catalogue 21 2, missing a header which is slightly 0
longer than ones in the rest of pages
Book 16 0 0
Marketing 4 0 0
brochure
Marketing 10 0 3, adding one graphic pattern in content
brochure to the background pattern)
Book 22 I, the footnote pattern is slightly longer 0
than the ones in the rest of pages
Marketing 2 0 0
brochure
Marketing 32 0 0
brochure
Weekly 24 I, missing footer which is longer and in 0
Journal slightly different position than ones in the
rest of the pages.
Table I: Results from background pattern extraction
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