Characterization of dermatological ulcers images for indexing and content-based retrieval

Author(s)

Silvio Moreto Pereira

• Document type: Master's Dissertation
• Press: São Carlos.
• Institution: Universidade de São Paulo (USP). Escola de Engenharia de São Carlos (EESC/SBD)
• Defense date: 2012-11-01

Examining board members

Paulo Mazzoncini de Azevedo Marques; Lauro Wichert Ana; Marcello Henrique Nogueira Barbosa

• Advisor: Paulo Mazzoncini de Azevedo Marques

Abstract

Skin ulcers are caused due to deficiency in the bloodstream. The diagnosis is made by a visual analysis of the affected area. Quantification of color distribution of the lesion by image processing techniques can aid in the characterization and response to treatment. The image processing steps involves skin ulcers related to segmentation, characterization and indexing. This analysis is important for classification, image retrieval and similar tracking the evolution of an injury. This project presents a study of segmentation techniques and characterization of color images of dermatological skin ulcers, based on the color models RGB, HSV, L*a*b* and L*u*v*, using their components in the extraction of texture and color information. Were used Machine Learning techniques, mathematical algorithms for segmentation and extraction of attributes, using a database containing 172 images in two versions. In recovery tests were used different distance metrics for performance evaluation and techniques of features selection. The results show good potential to support the diagnosis and monitoring of treatment progress with values up to 75% precision in recovery techniques, 0.9 area under the curve receiver-operating-characteristic) in classification, and 0.04 mean square error between the color composition of the automatically segmented image and the manually segmented image. In tests utilizing feature selection was observed a decrease in precision values of image retrieval (60%) and similar values in the classification\'s tests (0.85). (AU)

• FAPESP's process: 10/04526-9 - Dermatological ulcers image characterization for indexing and content-based retrieval.
• Grantee: Silvio Moreto Pereira
• Support Opportunities: Scholarships in Brazil - Master