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Feature detection

Gandalf currently has versions of the Canny edge detector, the Plessey corner detector and a line segment finder. The different feature detectors follow the same layered scheme, having a feature module which supports other feature detectors of the same type, below the specialised algorithm which implements a specific feature detector. Another important part of the Gandalf feature detectors is the local feature map. This encapsulates a local blocked representation of s feature map, allowing very fast search for features in regions of the image, and supporting the development of feature tracking/matching.

There is an important issue concerning coordinate frames for representing the feature positions, which is covered in Section 5.7.1 We then describe the different feature detection modules. For each feature type, we explain the use of the lower level feature module, which can be used to build new feature detectors, followed by the built-in feature detector.