# Snakes: Active contour models

@article{Kass2004SnakesAC, title={Snakes: Active contour models}, author={Michael Kass and Andrew P. Witkin and Demetri Terzopoulos}, journal={International Journal of Computer Vision}, year={2004}, volume={1}, pages={321-331} }

A snake is an energy-minimizing spline guided by external constraint forces and influenced by image forces that pull it toward features such as lines and edges. Snakes are active contour models: they lock onto nearby edges, localizing them accurately. Scale-space continuation can be used to enlarge the capture region surrounding a feature. Snakes provide a unified account of a number of visual problems, including detection of edges, lines, and subjective contours; motion tracking; and stereo…

## 15,518 Citations

Locating object contours in complex background using improved snakes

- Computer ScienceComput. Vis. Image Underst.
- 2007

An improved snake model associated with new regional similarity energy and a gravitation force field to attract the snake approaching the object contours efficiently is presented.

A semi-automatic system for edge tracking with snakes

- Computer ScienceThe Visual Computer
- 2005

An algorithm is presented that uses a block matching technique to guide the endpoints of the snake, optical flow to push the snake in the direction of the underlying motion, followed by the traditional snake edge-fitting minimization process for tracking facial features of an actor for driving computer animated characters.

Efficient Contour Detection Based On Improved Snake Model

- Mathematics, Computer ScienceInt. J. Pattern Recognit. Artif. Intell.
- 2004

This paper presents a new external force field, named gravitationforce field, for the snake model, and associates this force field with edge preserving smoothing to drive the snake for solving the problems.

A NOVELL ALGORITHM FOR ACTIVES CONTOUR MODELS: ADAPTIVE SNAKES

- 2005

This work presents a novel algorithm for optimizing deformable contour models. It overcomes an inherent problem of GVF snakes using a dynamic intervention at the curve evolution in a way that is…

An Initialization of Active Contour Models(Snakes) using Convex Hull Approximation

- Mathematics
- 2006

The Snakes and GVF used to find object edges dynamically have assigned their initial contour arbitrarily. If the initial contours are located in the neighboring regions of object edges, Snakes and…

Directional gradient vector flow for snakes

- MathematicsProceedings of the Fourth IEEE International Symposium on Signal Processing and Information Technology, 2004.
- 2004

Snakes, or active contour models, have been widely used in image segmentation. However, most present snake models cannot discern between positive and negative step edges. In this paper, a new type of…

Dynamic directional gradient vector flow for snakes

- Mathematics, MedicineIEEE Transactions on Image Processing
- 2006

Experimental results demonstrate that the DDGVF snake provides a much better segmentation than GVF snake in situations when edges of different directions are present which pose confusion for segmentation.

Growing snakes: active contours for complex topologies

- Mathematics, Computer SciencePattern Recognit.
- 2003

A technique is described that permits one to regularize the field of external forces that act on the Growing Snakes, which allow them to have good performance, even in the case of images with high levels of noise.

Guided energy-minimizing model for segmentation of vector fields

- Computer Science
- 2016

Active contours or snakes, are a group of image segmentation methods based on the idea of energy-minimizng curves. In this paper classical snake model with added Balloon Force is modified, granting…

Dividing snake algorithm for multiple object segmentation

- Computer Science
- 2002

This work further develops the segmented snake approach to contour detection and illustrates its flexibility by showing how it can be adapted to yield a dividing snake algorithm for use in multiple object segmentation.

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