Segmentação e extração das características de defeitos em imagens radiográficas de juntas soldadas e tubulações

• Ano de defesa: 2005
• Autor(a) principal: Schneider, Guilherme Alceu
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Centro Federal de Educação Tecnológica do Paraná; Curitiba; Programa de Pós-Graduação em Engenharia Elétrica e Informática Industrial
• Palavras-chave em Português: Processamento de imagens-técnicas digitais; Soldagem; Image processing-digital techniques; Welding
• Link de acesso: http://repositorio.utfpr.edu.br/jspui/handle/1/113

The visual inspection of radiographic images of welds and pipelines is a very repetitive task, very hard for humans. However, using digital radiographic images, it is possible to develop computational tools to be applied in the inspection process and to decrease the risks of inconsistent evaluations. This work presents a methodology to be applied in the automatic segmentation of defects in welds and pipes radiographic images, as well as to extract characteristics for the defects recognition. The tests and results, using the proposed methodology, show that it is possible to automatically perform the defect segmentation and characteristic extraction. As a result, some defects, difficult to be visually detected, were automatically segmented by the proposed method. Using some adjusting parameters, also proposed in this work, it is possible to adjust the method performance, obtaining more flexibility in the method applications. Two groups of images, originating from different sources, were tested and the results were satisfactory, since the defects, in almost all images, were segmented by the proposed method. A connected region labeling algorithm was used in order to make possible the automatic characteristics extraction for each detected defect. Besides, the proposed methodology shows to be robust also in some situations where other undesirable objects are presented in the image.