Raneem Ismail

57218864233

Publications - 7

A Novel Gradient-Weighted Voting Approach for Classical and Fuzzy Circular Hough Transforms and Their Application in Medical Image Analysis—Case Study: Colonoscopy

Publication Name: Applied Sciences Switzerland

Publication Date: 2023-08-01

Volume: 13

Issue: 16

Page Range: Unknown

Description:

Featured Application: The circular fuzzy Hough transform with gradient-weighted voting can be used for finding the contours of circle-like shapes, such as colorectal polyps on colonoscopy images, as well as other cases that require a given relative gradient edge around the circle-like objects. Classical circular Hough transform was proven to be effective for some types of colorectal polyps. However, the polyps are very rarely perfectly circular, so some tolerance is needed, that can be ensured by applying fuzzy Hough transform instead of the classical one. In addition, the edge detection method, which is used as a preprocessing step of the Hough transforms, was changed from the generally used Canny method to Prewitt that detects fewer edge points outside of the polyp contours and also a smaller number of points to be transformed based on statistical data from three colonoscopy databases. According to the statistical study we performed, in the colonoscopy images the polyp contours usually belong to gradient domain of neither too large, nor too small gradients, though they can also have stronger or weaker segments. In order to prioritize the gradient domain typical for the polyps, a relative gradient-based thresholding as well as a gradient-weighted voting was introduced in this paper. For evaluating the improvement of the shape deviation tolerance of the classical and fuzzy Hough transforms, the maximum radial displacement and the average radius were used to characterize the roundness of the objects to be detected. The gradient thresholding proved to decrease the calculation time to less than 50% of the full Hough transforms, and the number of the resulting circles outside the polyp’s environment also decreased, especially for low resolution images.

Open Access: Yes

DOI: 10.3390/app13169066

On Applying Gradient Based Thresholding on the Canny Edge Detection Results to Improve the Effectiveness of Fuzzy Hough Transform for Colonoscopy Polyp Detection Purposes

Publication Name: Smart Innovation Systems and Technologies

Publication Date: 2023-01-01

Volume: 332 SIST

Issue: Unknown

Page Range: 110-121

Description:

The possibilities of improving the effectiveness of fuzzy Hough transform calculations in the detection of colonoscopy image processing and polyp detection by gradient based preprocessing is studied. For the Hough transforms a black and white image consisting of line segments is necessary, thus most of the times an edge detected image is used as the basis of the transform. Here, the gradient magnitude values corresponding to the Canny edge pixels of the image are used for determining, which are the typical magnitude values for the polyp contours, in order to remove part of the non-contour edges from the image. Three publicly available databases with images and ground truth masks are used for testing, whether a general threshold for the gradients is applicable, but based on the histograms it seems to be not possible to generate a database independent normalized gradient based domain that can be used for sorting out the unnecessary edges.

Open Access: Yes

DOI: 10.1007/978-981-19-7842-5_10

WAYS OF IMPROVING OF ACTIVE CONTOUR METHODS IN COLON-OSCOPY IMAGE SEGMENTATION

Publication Name: Image Analysis and Stereology

Publication Date: 2022-01-01

Volume: 41

Issue: 1

Page Range: 7-23

Description:

As colonoscopy is the standard screening approach for colorectal polyps, and the first step of the correct classification and the efficient automatic diagnostics is the accurate detection and segmentation of the ex-isting polyps, it is worth researching systematically, how colonoscopy databases are responding to two of the most influential variational segmentation methods, the geodesic and Chan–Vese active contour meth-ods. Due to the quality variation of the colonoscopy databases, pre-processing steps are made. Then, 14 various filtered images are evaluated as different inputs for the active contour methods using the Sørensen–Dice Similarity Coefficient as a performance measurement metric. The effects of the initial mask shape and its size together with the number of iterations, contraction bias and smoothness factor are studied. In gen-eral, the Chan–Vese method showed more efficiency to match the actual contour of the polyp than the geodesic one with an initial mask possibly located within the polyp area. Preprocessing such as reflection removal, background subtraction and mean or median filtering can improve the Sørensen–Dice coefficient by up to 0.5

Open Access: Yes

DOI: 10.5566/ias.2604

The effect of different consequent setting on the effectiveness of Kóczy-Hirota fuzzy rule interpolation in colonoscopy image classification

Publication Name: 2022 57th International Scientific Conference on Information Communication and Energy Systems and Technologies Icest 2022

Publication Date: 2022-01-01

Volume: Unknown

Issue: Unknown

Page Range: Unknown

Description:

The effect of the refinement of the consequent categories in Kï¿czy-Hirota fuzzy rule interpolation is studied in the model system of colonoscopy image classification. The colonoscopy image segments are classified based on 99 antecedents, which are statistical parameters of the image segments. The number of consequents is increased from 2 - contains polyp, or does not contain polyp - to a more refined set distribution based on the polyp content of the image segment.

Open Access: Yes

DOI: 10.1109/ICEST55168.2022.9828693

On classical and fuzzy Hough transform in colonoscopy image processing

Publication Name: IEEE AFRICON Conference

Publication Date: 2021-09-13

Volume: 2021-September

Issue: Unknown

Page Range: Unknown

Description:

Hough transform is used to find lines on edge-filtered images that are given in parametric form. As the fuzzy extension of the Hough transform has been proven to be more robust in environments where the lines to be found by them are not strictly following the formula given by the parametric equation of the Hough transform due to noise and weak and blurred contours, in the following considerations, we study the applicability of the circular fuzzy Hough transform for analyzing colonoscopy pictures and detecting colorectal polyps.

Open Access: Yes

DOI: 10.1109/AFRICON51333.2021.9570897

On Metrics Used in Colonoscopy Image Processing for Detection of Colorectal Polyps

Publication Name: Smart Innovation Systems and Technologies

Publication Date: 2021-01-01

Volume: 216

Issue: Unknown

Page Range: 137-151

Description:

Colorectal cancer is nowadays the fourth cause of cancer death worldwide. Prevention of colorectal cancer by detection and removal of early stage lesions is of essential importance and has become a public health challenge worldwide. As the screening is carried out mainly by some sort of endoscope, and the endoscopic image processing is an important area of research and development, it is essential to know what kind of measures are used in determining whether polyp finding hit rates or miss rates are acceptable. It is rather natural to match the hit rate measures to the method itself; thus, in this contribution, the most typical polyp detecting methods are summarized shortly together with the metrics they use for evaluation of their results. However, in computer-aided diagnostics, the measure that is used by the medical community might differ from the measures typical in image processing researches. Also, the output of such polyp detecting methods is tested as inputs for active contour methods.

Open Access: Yes

DOI: 10.1007/978-981-33-4676-5_10

Fuzzy rulebase parameter determination for stabilized KH interpolation based detection of colorectal polyps on colonoscopy images

Publication Name: IEEE International Conference on Fuzzy Systems

Publication Date: 2020-07-01

Volume: 2020-July

Issue: Unknown

Page Range: Unknown

Description:

In the case of computer aided diagnosis it is advantageous to apply such computational intelligence methods, that can be related to direct measured data by means easily understandable to medical experts. Fuzzy reasoning, if the rulebase is generated from plausible statistical parameters of the image to be analysed, is easy to understand thus can be easily accepted by the society.In the case of colorectal polyps, which might develop into colorectal cancer, thus the population-wide screening would be advisable, more methods are available, but none of them is accepted as standard and effective method. A method based on simple statistical parameters and entropies of image segments is presented, and the effect of determining the rulebase parameters on the efficiency of finding the polyp segment is studied for stabilized Koczy-Hirota rule interpolation.

Open Access: Yes

DOI: 10.1109/FUZZ48607.2020.9177839