PURPOSE: In scoliosis monitoring, tracked ultrasound has been explored as a safer imaging alternative to traditional radiography. The use of ultrasound in spinal curvature measurement requires identification of vertebral landmarks such as transverse processes, but as bones have reduced visibility in ultrasound imaging, skeletal landmarks are typically segmented manually, which is an exceedingly...

In this paper, we present a new shadow mapping technique that improves upon the quality of perspective and uniform shadow maps. Our technique uses a perspective transform specified in light space which allows treating all lights as directional lights and does not change the direction of the light sources. This gives all the benefits of the perspective mapping but avoids the problems inherent in...

In the process of moving target detection, moving objects and their shadows are often extracted both. It leads to the failure of moving target positioning, segmentation, tracking and classification in the moving-object detection. Thus the shadow removal is an important task in the intelligent monitoring system. In the process of shadow removal, using color features to detect shadow is easy to c...

Shadow detection plays an important role in digital aerial image processing. In this paper, shadow is treated as a special kind of image degradation. Shadow region commonly has lower brightness than non-shadow region. And, shadow region tends to have a slow gradient change in luminance value, or means to have some conformability. On the basis of these analyses, an edge detector is proposed firs...

We propose the concepts of Virtual Light and Virtual Shadow with the aim of achieving a Mixed Reality Environment focused on shadows. In this proposal, we divide the concept of Virtual Shadow into four categories, and among them, implement four types of interactive applications: (a) real to virtual shadow for rigid objects, (b) real to virtual shadow for non-rigid objects, (c) image-based virtu...

The high-quality simulation of the penumbra effect in real-time shadows is a challenging problem in shadow mapping. The existing shadow map filtering techniques are prone to aliasing and light leaking artifacts which decrease the shadow visual quality. In this paper, we aim to minimize both problems with the Euclidean distance transform shadow mapping. To reduce the perspective aliasing artifac...

This paper proposes a novel foreground detection method which estimates the color changes in shadow regions by using a solar spectral model. In conventional method, since it is assumed that only brightness changes from background in shadow regions, shadow regions are extracted falsely as foreground in the case where color in the shadow region also changes in outdoor daytime environment. The pro...

A de-shadowing technique is presented for multispectral and hyperspectral imagery over land acquired by satellite/airborne sensors. The method requires a channel in the visible and at least one spectral band in the near-infrared (0.8–1mm) region, but performs much better if bands in the short-wave infrared region (around 1.6 and 2.2mm) are available as well. The algorithm consists of these majo...

The paradigm of the rubber hand illusion was applied to a shadow to determine whether the body-shadow is a good candidate for the alternative belonging to our body. Three kinds of shadows, a physical hand, a hand-shaped cloth, and a rectangle cloth, were tested for this purpose. The questionnaire results showed that both anatomical similarity and visuo-proprioception correlation were effective ...