A New Scale Invariant Optimized Chain Code for Nastaliq Character Representation

Abstract

S cale invariant code is a code that will remain identical even when we change the scale of an object means when we scale in/out, the output chain code will remain same, so it can be used in object representation and recognition. The algorithm is developed for Nastaliq characters, but is it general in nature and can be used for boundary representation of any object. The basic idea is that instead of storing and computing the chain code of each pixel, we create segments by using corner points and develop a new code for the segments not for pixels, and that code will be scale invariant and of course will be much shorter than the chain code. A segment is a portion between two corner points; as the ratio between segments will remain same even when we change the scale of image, so we compute the ratio of each segment to the whole image, and will finally compute optimized scale invariant code.

Arabic script based character segmentation: A review

“…In 2010, Rehman et al [17] published a freeman chain code representation method which is segmentation based scale invariant and optimized boundary representation code for Nastaleeq characters. They developed new small code instead of storing and computing the chain code of each pixel for the segments of characters, that code is scale invariant (independent of scale in/out).…”

Fuzzy Clustering of Image Trademark Database and Preprocessing Using Adaptive Filter and Karhunen–loève Transform

“…The cases of translation and scaling can be very well handled by the use of chain codes for representing object boundaries. 16 The chain codes of an image and its scaled version can be normalized to same value. 16 Similarly translated objects will also have the same chain code values.…”

“…16 The chain codes of an image and its scaled version can be normalized to same value. 16 Similarly translated objects will also have the same chain code values. The major cases of trademark infringement consist of copying of objects from a reputed trademark image, rotating it by a certain angle and pasting it.…”

An Efficient Contour Tracking and Coding Algorithm Based on Vertex Chain Code

“…For example, Wang et al [3] applied chain codes for pavement crack classification. Rehman [4] proposed an algorithm for nastaliq character representation using a new scale invariant optimized chain code. Ranjan and Chhanda [5] presented an image registration algorithm using object shape's chain code.…”