An original method is proposed to extract the most significant volumetric structures in an illuminance image. The method proceeds in three levels of organization managed by generic grouping principles: (i) from the illuminance image to a more compact representation of its contents by generic structural information extraction leading to a basic contour primitive map; (ii) grouping of the basic p...

We present a new background-subtraction technique fusing contours from thermal and visible imagery for persistent object detection in urban settings. Statistical background-subtraction in the thermal domain is used to identify the initial regions-of-interest. Color and intensity information are used within these areas to obtain the corresponding regions-of-interest in the visible domain. Within...

It is extremely difficult to locate the contour of the prostate in B-scan ultrasound images automatically by computer because of low resolution and high noise levels. In this paper we present a semi-automatic prostate contour extration scheme, which is based on the wavelet transform and active contour models, or snakes. The ultrasound image is first decomposed into edge maps at different resolu...

To estimate motion, the edges of a moving object can be detected using Active Contours. After detecting the edges throughout the duration of the motion, the contours are registered together in order to obtain the motion model parameters. This idea can be applied to motion artifacts in Magnetic Resonance Images (MRI) which are caused by patient motion during the acquisition of an MRI. Thus, if t...

The process of converting an analog map into struc tured digitized information requires several di erent operations which are all time consuming when per formed manually Strictly automatic processing is not always a possible solution and an interactive approach can then be an alternative This paper describes a tool for map conversion fo cusing on the functionality for extraction of line struc t...

Contours maps (such as topographic maps) compress the information of a function over a two-dimensional area into a discrete set of closed lines that connect points of equal value (isolines), striking a fine balance between expressiveness and cognitive simplicity. They allow humans to perform many common sense reasoning tasks about the underlying function (e.g. elevation). This paper analyses an...

Mapping specific landform entities in the past is mainly achieved by manually examining contour lines on topographic maps. Automated delimitation of specific landform from digital elevation data remains difficult in geomorphologic mapping. This paper presents a method to automatically identify five common surface features of karst landscapes: isolated karst hill or sinkhole, clustered karst hil...

During an 11 days mission in February 2000 the Shuttle Radar Topography Mission (SRTM) collected data over 80% of the Earth's land surface, for all areas between 60 degrees N and 56 degrees S latitude. Since SRTM data became available, many studies utilized them for application in topography and morphometric landscape analysis. Exploiting SRTM data for recognition and extraction of topographic ...

Significant progress has been made in boundary detection with the help of convolutional neural networks. Recent models not only focus on real object but also “crisp” boundaries (precisely localized along object's contour). There are two methods to evaluate crisp performance. One uses more strict tolerance measure distance between ground truth and detected contour. The other focuses evaluating c...

Telemedicine is growing and there is an increased demand for faster image processing and transmitting diagnostic medical images. Identifying and extracting the region of interest (ROI) accurately is an important step before coding and compressing the image data for efficient transmission or storage. The usual approach to extract ROI is to apply contour segmentation method. Chan-Vese active cont...