Incremental attribute computation and image manipulation using morphological trees

Morphological trees are image representations that can be used in a wide range of applications from medical imaging to digital photography. Morphological trees are interesting representations because they hierarchically encode the connected components (with and without their holes filled) according...

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Detalles Bibliográficos
Autor: Silva, Dênnis José da
Tipo de recurso: tesis doctoral
Estado:Versión publicada
Fecha de publicación:2025
País:Brasil
Institución:Universidade de São Paulo (USP)
Repositorio:Biblioteca Digital de Teses e Dissertações da USP
Idioma:inglés
OAI Identifier:oai:teses.usp.br:tde-02082025-161749
Acceso en línea:https://www.teses.usp.br/teses/disponiveis/45/45134/tde-02082025-161749/
Access Level:acceso abierto
Palabra clave:Árvore de formas
Árvores de componentes
Árvores morfológicas
Attribute computation
Component trees
Computação de atributos
Image manipulation
Manipulação de imagens
Morphological trees
Tree of shapes
Descripción
Sumario:Morphological trees are image representations that can be used in a wide range of applications from medical imaging to digital photography. Morphological trees are interesting representations because they hierarchically encode the connected components (with and without their holes filled) according to their subset relationship. In this way, we can analyse and process connected regions of the images based on the hierarchy represented by the tree. A common morphological tree application pipeline consists of building the tree, computing attributes, processing the tree based on the tree structure and attributes of each node, and outputting results. Consequently, efficient attribute computation is a recurrent demand for unlocking new morphological tree applications. In this thesis, we describe our research on how to efficiently compute bit-quad counts, contours and distance transforms in morphological trees by exploiting the subset relationship encoded in trees for reuse of the attribute computation of the child nodes into their parent. First, we review how we can count bit-quads in component trees incrementally from the leaves to the root. Next, we design a novel incremental algorithm to count bit-quads in the tree of shapes. Then, we design a novel incremental method that can extract the contour of the nodes of component trees by counting the number of background neighbours of the pixels. Finally, we use our incremental contour method and Differential Image Foresting Transform to differentially compute the distance transform of component trees. We experimentally show that our differential and incremental methods are faster than non-incremental node-reconstruction approaches. We also explore the usage of morphological trees for image manipulation. In particular, we propose a novel morphological tree visualisation using icicle plots for node selection. In this visualisation, the nodes are coloured by an iso-illuminant colour map according to an attribute which aids the user in selecting the nodes. Then, the selected nodes can be manipulated using a spline-based dense medial descriptor. In summary, the thesis shows that we can compute bit-quad counts, contours, and distance transforms in morphological trees quickly by reusing the computation on the child nodes into their parent. It also discusses a software application of morphological trees for image manipulation.