We present an edge-based active contour model, which is an extension of our MAC model to deal with the initialization dependency problem that commonly appears in edge-based approaches. Its dynamic force field, unique bidirectionality, and constrained diffusion-based level set evolution provide great freedom in contour initialization and show significant improvements in initialization independency compared to other edge-based techniques. It can handle more sophisticated topological changes than splitting and merging. It provides new potentials for edge-based active contour methods, particularly when detecting and localizing objects with unknown location, geometry, and topology.
Example results - recovering objects with internal holes and inhomogeneous intensity
Initial Contour | Evolving Contours | Stabilized Contour |
Geodesic | |
GGVF | |
GeoGVF | |
Chan–Vese | |
Proposed method |
Example results - bidirectionality (initialization on both sides of an object boundary)
GGVF | |
Proposed method |
Example results - initialization inside an object boundary
Basic MAC | |
Proposed method (lambda=1) | |
Proposed method (lambda=2) |
Example results - recovering weak/broken edges using proposed method
Weak/Broken Edges | Initial Shape | Evolving Shapes | Stabilized Shape |
Example results - initialization flexibility using proposed method
Random initialization | |
Cross-boundary initialization | |
Single inside initialization | |
No initialization (lambda=1) | |
No initialization (lambda=2) |
Example results - recovering noisy complex shape using proposed method
Complex shape with 50% Gaussian noise and its recovery result using force diffusion | |
Weak/broken edges after heavy edge thresholding and its recovery result without force diffusion |
Example results - segmentation of a bone CT image
Geodesic | |
GGVF | |
GeoGVF | |
CPM | |
Chan–Vese | |
Proposed method (no initialization) | |
Proposed method (cross-boundary initialization) | |
Proposed method (horizontal-line initialization) |
Example results - segmentation of color images using proposed method
Skin lesion image with weak edges & noise | Horse image with large color variations & weak edges | Blood vessel image with complex shape & topology, varying intensity, & weak edges | Fish swarm image with inhomogeneous color distribution, complex topology, & weak edges | |
No initialization | ||||
Horizontal-line initialization |
Publications