IEEE Transactions on Circuits and Systems for Video Technology

We explored the response of the human visual system to mixed-resolution stereo video-sequences, in which one eye view was spatially or temporally low-pass filtered. It was expected that the perceived quality, depth, and sharpness would be relatively unaffected by low-pass filtering, compared to the case where both eyes viewed a filtered image. Subjects viewed two 10-second stereo video-sequences, ... View full abstract»

We propose a modified overlapped block-matching (OBM) scheme for stereo image coding. OBM has been used in video coding but, to the best of our knowledge, it has not been applied to stereo image coding to date. In video coding, OBM has proven useful in reducing blocking artifacts (since multiple vectors can be used for each block), while also maintaining most of the advantages of fixed-size block ... View full abstract»

Spurious range data pose a serious visualization problem with active light systems, as they can totally deform the acquired 3-D shapes. This work presents a technique for their detection based on geometrical considerations. The proposed method does not need extra hardware and can be used effectively for the provision of post-processing noise removal. The method has been extensively tested on real ... View full abstract»

Rendering and animating in real-time a multitude of articulated characters presents a real challenge, and few hardware systems are up to the task. Up to now, little research has been conducted to tackle the issue of real-time rendering of numerous virtual humans. This paper presents a hardware-independent technique that improves the display rate of animated characters by acting on the sole geometr... View full abstract»

Conventional ray-space acquisition systems require very precise mechanisms to control the small movement of cameras or objects. Most of them adopt camera with a gantry or a turntable. Although they are good for acquiring the ray-space of small objects, they are not suitable for ray-space acquisition of very large structures, such as a building, tower, etc. This paper proposes a new ray-space acqui... View full abstract»

Two experiments are presented that were aimed to investigate the effects of stereoscopic filming parameters and display duration on observers' judgements of naturalness and quality of stereoscopic images. The paper first presents a literature review of temporal factors in stereoscopic vision, with reference to stereoscopic displays. Several studies have indicated an effect of display duration on p... View full abstract»

We present prototypes of autostereoscopic displays which allow single users to experience stereoscopic vision without the need for special eye glasses or helmet-mounted displays. The design of the displays is based on lenticular raster plates and includes a number of novel concepts for tracking of raster plates or projection lenses to account for changes of the viewers position in front of the scr... View full abstract»

This paper focuses on the scanning methods of a field-sequential stereoscopic display system. We examined the advantages and disadvantages of several scanning methods to identify the most suitable one for the field-sequential stereoscopic display technique. An evaluation test using a system with 525 scanning lines and a 120-Hz field frequency was conducted. The results show that the picture qualit... View full abstract»

An autostereoscopic 3-D displaying technique that uses fan-likely placed multiple light beams in a light array with 2-D raster scanning is proposed. This technique is capable of displaying multiple perspective views at high resolution because the number of views only depends on the number of light beams, while the number of light beams does not depend on the resolution of each view. Moreover, doze... View full abstract»

A system for the automatic reconstruction of real-world objects from multiple uncalibrated camera views is presented. The camera position and orientation for all views, the 3-D shape of the rigid object, as well as the associated color information, are recovered from the image sequence. The system proceeds in four steps. First, the internal camera parameters describing the imaging geometry are cal... View full abstract»

A common limitation of many techniques for 3-D reconstruction from multiple perspective views is the poor quality of the results near the object boundaries. The interpolation process applied to "unstructured" 3-D data ("clouds" of non-connected 3-D points) plays a crucial role in the global quality of the 3-D reconstruction. We present a method for interpolating unstructured 3-D data, which is abl... View full abstract»

We propose an algorithm to construct a 3-D surface model from a set of range data, based on non-uniform rational B-splines (NURBS) surface-fitting technique. It is assumed that the range data is initially unorganized and scattered 3-D points, while their connectivity is also unknown. The proposed algorithm consists of three stages: initial model approximation employing K-means clustering, hierarch... View full abstract»

A novel algorithm for the generation of background sprite images from multiview image sequences is presented. A dynamic programming algorithm, first proposed by Grammalidis and Strintzis (see IEEE Trans. Circuits Syst. Video Technol., vol.8, p.328-44, 1998) using a multiview matching cost, as well as pure geometrical constraints, is used to provide an estimate of the disparity field and to identif... View full abstract»

In conventional predictive quantization schemes for 3-D mesh geometry, excessively large residuals or prediction errors, although occasional, lead to visually unacceptable geometric distortion. This is due to the fact that they cannot limit the maximum quantization error within a given bound. In order to completely eliminate the visually unacceptable distortion caused by large residuals, we propos... View full abstract»

We propose a novel approach for producing special visual effects by fusing multiple differently focused images. This method differs from conventional image fusion techniques because it enables us to arbitrarily generate object-based visual effects such as blurring, enhancement, and shifting. Notably, the method does not need any segmentation. Using a linear imaging model, it directly generates the... View full abstract»

In the Guest Editorial of the December 1999 issue of this TRANSACTIONS, the last sentence in the biography of Rob Koenen should read as follows: "Dr. Koenen is an Associate Editor of IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY." View full abstract»