The subject of this chapter is to describe selected topics on contour extraction, approximation and compression in spatial domain. Contours are treated as important image structure required in many applications, for example in analysis of medical image, computer vision, robot guidance, pattern recognition etc. Contour compression plays important role in many practical tasks associated with cont...

Feature extraction algorithms delivering accurate results are computational intensive and cannot keep up with the demanded processing times on single processor systems in automated micropart assembly tasks. For this case an improved contour tracer for real-time edge-line extraction, using adaptive local thresholds, is introduced. In combination with an effective start point search, that concent...

We present a method for object class detection in images based on global shape. A distance measure for elastic shape matching is derived, which is invariant to scale and rotation, and robust against non-parametric deformations. Starting from an over-segmentation of the image, the space of potential object boundaries is explored to find boundaries, which have high similarity with the shape templ...

We present two new corner detectors; one works by using dissimilarity along the contour direction to detect curves in the image contour and the other estimates image curvature along the contour direction. These operators are fast, robust to noise, and require no subjective thresholding.

We study the challenging problem of detecting carried objects (CO) in surveillance videos. For this purpose, we formulate CO detection in terms of determining a person’s contour hypothesis and detecting CO by exploiting the remaining contours. A hypothesis mask for a person’s contours is generated based on an ensemble of contour exemplars of humans with different standing and walking poses. Con...

Interactive edge detection is used in both graphics art tools and in tools for building anatomical models from serially sectioned images. To build models, contours are traced and later triangulated. Contour tracing is time-consuming because of the quantity and fidelity of points needed, and expensive because of the background training required of individuals who do the tracing. Here we report e...

Contour-based object detection can be formulated as a matching problem between model contour parts and image edge fragments. We propose a novel solution by treating this problem as the problem of finding dominant sets in weighted graphs. The nodes of the graph are pairs composed of model contour parts and image edge fragments, and the weights between nodes are based on shape similarity. Because...

Object aware video rate transcoding can significantly improve the perceptual quality of relatively low bit-rate video. However, precise object detection in arbitrary video scenes is computationally challenging. This paper presents an interesting experimentation with a live eyegaze tracker which suggests that object detection, particularly for perceptual encoding, may not have to be precise. Ind...

The accuracy and execution speed of a force controlled contour-following task is limited if the shape of the workpiece is unknown. This is even more true when the workpiece contour contains corners. This paper shows how a hybrid vision/force control approach at corners in planar-contour following results in a more accurate and faster task execution. The vision system is used to measure online t...