Extraction method of rectangle seal graphics with border based on form feature

Abstract

The invention discloses an extraction method of rectangle seal graphics with border based on form feature. The method comprises the following steps: (1) screening connected components of a target image foreground layer, and removing small connected components dissatisfying seal dimension specification in the target image; (2) screening connected components of a target image background layer and removing the connected components which are far larger than or smaller than the seal dimension specification; (3) adopting watershed algorithm in image segmentation to extract skeleton of closed graphics in the target image, using the longest tour length of skeleton point in the seal to judge rectilinear direction and remove flash; (4) extracting the seal according to the seal dimension specification provided by users. The method of the invention can fast and effectively detect a plurality of rectangle seals with unfixed number in the image, and has the advantages of high detection precision, fast speed, strong anti-interference and the like.

Description

Technical field: [0001] The invention belongs to the field of text image processing, and relates to a method for extracting stamp graphics with borders based on shape features, in particular to a method for extracting and recognizing regular graphics. Background technique: [0002] In recent years, some scholars have successively carried out research on the automatic detection and extraction of seals. Noting that the stamp graphics in bills are usually red, these studies focus on the extraction of stamp graphics with the help of color features. By transforming the image into a certain color space, such as HSI space, and then adopting the threshold segmentation technique to extract the seal. Since the stamp may also be disturbed by objects such as red writing lines, removal of red writing lines, etc. is usually required. The main disadvantages of this method are that the scanned image tends to drift in color and, since the stamp is usually applied to a paper document, it in...

AI Technical Summary

Problems solved by technology

The main disadvantages of this method are that the scanned image tends to drift in color and, since stamps are usually applied to paper documents, they inevitably overlap other objects

However, this method is usually slow and difficult to detect in real time, and when the number of stamps in the image is not fixed, the HOUGH transform method usually has many false detections

This is mainly due to the difficulty in effectively selecting the threshold when determining the local extremum in the accumulation array of the HOUGH transform.

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