Soumen Bag

Indian Institute of Technology (ISM) Dhanbad | ISM · Department of Computer Science and Engineering

Glioma has emerged as the deadliest form of brain tumor for human beings. Timely diagnosis of these tumors is a major step towards effective oncological treatment. Magnetic Resonance Imaging (MRI) typically offers a non-invasive inspection of brain lesions. However, manual inspection of tumors from MRI scans requires a large amount of time and it i...

Pen ink analysis is an essential step for establishing the integrity of a handwritten document. Traditional approaches for analyzing the ink are based on destructive techniques like thin layer chromatography, high performance liquid chromatography, etc. There are several non-destructive techniques too which focus on multi-spectral imaging on variou...

Character recognition of the script is the most vital step of Optical Character Recognition and the recognition accuracy directly affects the optical character recognition performance. Recognition of the script is fully achieved when all the components of the script are recognized completely. The conjunct character of the Devanagari script is one s...

Background and Objectives: Among different cancer types, glioma is considered as a potentially fatal brain cancer that arises from glial cells. Early diagnosis of glioma helps the physician in offering effective treatment to the patients. Magnetic Resonance Imaging (MRI)-based Computer-Aided Diagnosis for the brain tumors has attracted a lot of att...

Copy-move forgery is one of the well-known image forgery technique which exploits regions of the same image to create forged image by replicating or hiding authentic content of the original image. Original images can also contain similar looking but authentic objects. In such cases, identification of authentic and tampered images is a complicated t...

Decomposition of a word into a set of appropriate pseudo-characters is a challenging task in case of a cursive script like Bangla. Segmentation-free approach bypasses the decomposition problem entirely and treats the handwritten word as an individual entity. From the literature, we found that the accuracy of handwritten Bangla cursive word recognit...

Multi-oriented handwritten documents require additional preprocessing for segmentation and subsequent phases to work accurately in handwritten recognition systems. Skew correction is one such additional phase. Appearance of skew in multi-oriented Indian language based handwritten document is higher due to the presence of cursive nature. In the curr...

Copy-move forgery is one of the most frequently utilized image tampering technique which uses the segment of the same image to produce manipulated image by duplicating or concealing image regions. To remove suspicious traces of forgery, various attacks are applied over the tampered image which make forgery detection process too complicated. We prop...

Copy‐move image forgery is one of the most popular image tampering technique which can be performed for vicious purposes. In this forgery technique, selected region is copied and pasted at different locations on the same image to produce a manipulated image. Such forgery is denigratory as it can alter the image content by hiding or appending visual...

Fraudsters often alter handwritten contents in a document in order to achieve illicit purposes. At times, this may result in financial and mental loss to an individual or an organization. Hence, ink analysis is necessary to identify such an alteration. Convolution Neural Network (CNN) can be used to identify such cases of alteration, as CNN has eme...

Segmentation of tissues in brain magnetic resonance (MR) images has a crucial role in computer‐aided diagnosis (CAD) of various brain diseases. However, due to the complex anatomical structure and the presence of intensity non‐uniformity (INU) artefact, the segmentation of brain MR images is considered as a complicated task. In this study, the auth...

One of the most popular image forgery technique is copy-move forgery. In this technique, one or more segments are copied and affixed at different positions within the image. This forgery technique is highly grievous as it can manipulate an image in various ways (such as by presenting additional information or by concealing the genuine information o...

Numeral recognition plays a vital role in making automated systems like postal address sorting and license plate recognition. In a multilingual country like India, more often, the multiple languages are mixed while writing. Numeral recognizer systems which can handle more than one language are very much useful to recognize numerals of various scrip...

The addition of new words in handwritten documents such as bank cheques, bills, and notes is considered as common crime. Such immoral activities on handwritten documents have a bad effect on the victim in terms of mental and financial loss. For facilitating an impartial judicial process, it is important to differentiate between the used pen inks. E...

Magnetic Resonance Images (MRI) are often contaminated by rician noise at the acquisition time. This type of noise typically deteriorates the performance of disease diagnosis by a human observer or an automated system. Thus, it is necessary to remove the rician noise from MRI scans as a preprocessing step. In this letter, we propose a novel Convolu...

Alteration of words in handwritten financial documents such as cheques, medical claims, and insurance claims may lead to monetary loss to the customers and financial institutions. Hence, automatic identification of such alteration in documents is a crucial task. Therefore, an ink color based analysis using Convolutional Neural Network (CNN) automat...

Copy move forgery detection is a rapidly growing research area in the field of blind image forensics. Image forgery means fraction of image is copied and pasted within the same image to entrap the end users and distort the originality of the information. Methods introduced so far faces problems in detecting forged region present in large size image...

Offline recognition of handwritten text in Indian regional scripts is a major area of research as nearly 910 million people use such scripts in India. Most of the reported research works on Indian script-based optical character recognition (OCR) system have focused on a single script only. Research for developing methodologies that are capable of h...

In the research field of document image analysis, especially in handwritten documents, fraudulent alteration identification is a crucial task due to several forgery activities that are happening for few decades which affect a nation economically. In this paper, we are differentiating visually identical ink of different pens used for alteration in s...

Copy–move Dixit, Anuja is a well-known image Soumen, Bag technique. In this image manipulation method, a certain area of the image is replicated and affixed over the same image on different locations. Most of the times replicated segments suffer from multiple post-processing and geometrical attacks to hide sign of tampering. We have used block-base...

Since digitization is yet to be adopted globally, handwritten documents are still in use in many places. Handwritten documents are prone to get forged thanks to acts like the versatility of tampering which are very frequent among skilful fraudsters. Our research work focuses on one of the major problems to detect whether a document is treated as fa...

Filling up forms at post offices, railway counters, and for application of jobs has become a routine for modern people, especially in a developing country like India. Research on automation for the recognition of such handwritten forms has become mandatory. This applies more for a multilingual country like India. In the present work, we use readily...

Multilingual Optical Character Recognition (OCR) is difficult to develop as different languages exhibit different writing and structural characteristics and it is very difficult to generalize their segmentation process. Character segmentation plays an important role in developing OCR for handwritten languages. The exactness of character segmentatio...

Most segmentation algorithms for Indian scripts require some prior knowledge about the structure of a handwritten word to efficiently fragment the word into constituent characters. Zone detection is a considerably used strategy for this purpose. Headline estimation is a salient part of zone detection. In the present work, we propose a method that u...

Proper recognition of complex-shaped handwritten compound characters is still a big challenge for Bangla OCR systems. In this paper, we propose a novel shape decomposition-based segmentation technique to decompose the compound characters into prominent shape components. This shape decomposition reduces the classification complexity in terms of less...

In handwritten Bank cheques, addition of new words using similar color pen can cause huge loss. Hence, it is important to differentiate pen ink used in these types of documents. In this work, we propose a non-destructive pen ink differentiation method using statistical features of ink and multi-layer perceptron (MLP) classifier. Large sample of blu...

Substantial size of convoluted conjunct characters in Bengali language makes the recognition process burdensome. In this paper, we propose a structural disintegration based segmentation technique that fragments the conjunct characters into discernible shapes for better recognition accuracy. We use a set of structure based segmentation rules that bi...

Face is the most easily identifiable characteristic of a person. Variations in facial expressions can be easily recognized by humans, while it is quite difficult for machines to recognize faces portraying varying facial expressions, pose, and illumination conditions efficiently. Face recognition works as a combination of feature extraction and clas...

Face is the most easily identifiable characteristic of a person. Variations in facial expressions can be easily recognized by humans, while it is quite difficult for machines to recognize faces portraying varying facial expressions, pose, and illumination conditions efficiently. Face recognition works as a combination of feature extraction and clas...

Thinning of character images is a big challenge. Removal of strokes or deformities in thinning is a difficult problem. In this paper, we have proposed a nearest opposite contour pixel based thinning strategy used for performing skeletonization of printed and handwritten character images. In this method, we have used shape characteristics of text to...

The proper character level segmentation of printed or handwritten text is an important preprocessing step for optical character recognition (OCR). It is noticed that the languages having cursive nature in writing make the segmentation problem much more complicated. Hindi is one of the well known language in India having this cursive nature in writi...

Binary image thinning has wide applications in image processing, machine vision, and pattern recognition. Thinning is a preprocessing step to obtain single-pixel-thin skeleton for document imaging and pattern analysis. Indian languages are complex in character shape than Latin, Chinese, Japanese, and Korean languages. The performance of existing th...

Abstract A novel technique for binarization with stroke preservation of faint characters in degraded documents is proposed. It works in a multi-scale framework with an adaptive-interpolative thresholding technique. Instead of computing a global threshold value, it computes the local threshold values for a small set of grid points by observing the i...

The proper character level segmentation of printed or handwritten text is an important preprocessing step for optical character recognition (OCR). It is noticed that the languages having cursive nature in writing make the segmentation problem much more complicated. Hindi is one of the well known language in India having this cursive nature in writi...

Thinning which is an important preprocessing step for character recognition is often subject to several kinds of distortion. Junction point distortion is a major imperfection in thinned images especially for handwritten Indian scripts due to the presence of large number of complicated junctions in them. Such distortion does allow the optical charac...

Thinning is an important preprocessing operation used in different document image processing and analysis applications. The main objective of thinning is to obtain singlepixel thin skeleton without any shape distortion. It is noticed that documents written in ink-sketch pens and scanned with high precision scanners suffer from high degree of uneven...

The past few decades have witnessed an intensive research on optical character recognition (OCR) for Roman, Chinese, and Japanese scripts. A lot of work has been also reported on OCR efforts for various Indian scripts, like Devanagari, Bangla, Oriya, Tamil, Telugu, Malayalam, Kannada, Gurmukhi, Gujarati, etc. In this paper, we present a review of O...

In this paper, we present a novel technique for detection of concave regions as a structural information of character images. The problem difficulty lies in reporting all concavities irrespective of the viewing direction on the 2D plane. In our approach, we detect concave regions by analyzing the sequence of discrete turns taken to describe the cha...

Segmentation of cursive handwriting is one of the most challenging problems in the area of handwritten character recognition. In this paper, we propose a novel approach towards character segmentation in a handwritten document. It is based on the vertex characterization of outer isothetic polygonal covers so that each cover corresponds to a particul...

In this paper we propose a thinning methodology applicable to character images. It is novel in terms of its ability to adapt to local character shape while constructing the thinned skeleton. Our method does not produce many of the distortions in the character shapes which normally result from the use of existing thinning algorithms. The proposed th...

A novel technique for binarization of degraded documents is proposed. It works in a multi-scale framework with an adaptive-cum-interpolative thresholding as a modification of Otsu's method. Instead of computing a global threshold value for an input document image, it computes the local threshold values for a small set of grid points by observing th...

Facial expressions convey non-verbal cues, which play an important role in interpersonal relations. Automatic recognition of human face based on facial expression can be an important component of natural human-machine interface. It may also be used in behavioral science. Although human being can recognize the face practically without any effort, bu...

Digital skeleton of character images, generated by thinning method, has a wide range of applications for shape analysis and classification. But thinning of character images is a big challenge. Removal of spurious strokes or deformities in thinning is a difficult problem. In this paper, we propose a contour-based thinning method used for performing...

In this paper, we present novel topological features based on the structural shape of a character. We detect the convexshaped segments formed by the various strokes. The convex segments are then represented with shape primitives from a repertoire. The character is represented as a spatial layout of convex segments. We formulate feature templates fo...

Feature selection and extraction plays an important role in different classification based problems such as face recognition, signature verification, optical character recognition (OCR) etc. The performance of OCR highly depends on the proper selection and extraction of feature set. In this paper, we present novel features based on the topography o...

Facial expressions convey non-verbal cues, which play an important role in interpersonal relations. Automatic recognition of human face based on facial expression can be an important component of natural human-machine interface. It may also be used in behavioural science. Although human can recognize the face practically without any effort, but rel...

Thinning of character images is a big challenge. Removal of strokes or deformities in thinning is a difficult problem. In this paper, we have proposed a medial axis based thinning strategy used for performing skeletonization of printed and handwritten character images. In this method, we have used shape characteristics of text to get skeleton of ne...

The main challenge in recognizing handwritten characters is to handle large-scale shape variations in the handwriting of different individuals. In this paper, we present a novel handwritten character recognition method based on the structural shape of a character irrespective of the viewing direction on the 2D plane. Structural shape of a character...

In this paper, we present novel features based on the topography of a character as visible from different viewing directions on a 2D plane. By topography of a character we mean the structural features of the strokes and their spatial relations. In this work we develop topographic features of strokes visible with respect to views from different dire...

The thinning methodology is novel in terms of its ability to incorporate character shape specific knowledge while constructing the thinned skeleton. But removal of spurious strokes or shape deformation in thinning is a difficult problem. In this paper, we have proposed a novel medial-axis based thinning strategy used for performing skeletonization...