This paper describes recent advances in a number of R&D areas that are believed to provide 'key technologies' for the further development of a novel, digital, broadcast 3D-TV system. The provided results are part of the outcome of the European IST project ATTEST (Advanced Three-Dimensional Television System Technologies), a two-year research initiative that was finalized in March 2004. The paper covers some essential parts of the envisaged 3D signal processing chain such as the real-time generation of "virtual" stereoscopic views from monoscopic color video and associated per-pixel depth information as well as the efficient compression and the backwards-compatible transmission of this advanced data representation format using state-of-the-art video coding standards such as MPEG-2 (color data) and MPEG-4 Visual, resp. Advanced Video Coding (depth data). Furthermore, the paper also describes the development of a new, single-user autostereoscopic 3D-TV display (Free2C). This novel, high-quality 3D device utilizes a lenticular lens raster to separate two individual perspective views, which are presented simultaneously on an underlying LC panel. To provide the user with a satisfying 3D reproduction within a sufficiently large viewing area - a major problem for many state-of-the-art autostereoscopic 3D displays - the lenticular is constantly readjusted according to the viewer's actual head position, which is measured by a highly accurate, video-based tracking system. This approach allows for a variation of the viewing distance within a range of 400 mm to 1100 mm as well as horizontal head movements within a range of about ±30°. The feasibility of the new 3D-TV concept is proved through extensive human factors evaluations of the before-described algorithms and components.
This paper presents details of a system that allows for an evolutionary introduction of depth perception into the existing 2D digital TV framework. The work is part of the European Information Society Technologies (IST) project "Advanced Three-Dimensional Television System Technologies" (ATTEST), an activity, where industries, research centers and universities have joined forces to design a backwards-compatible, flexible and modular broadcast 3D-TV system. At the very heart of the described new concept is the generation and distribution of a novel data representation format, which consists of monoscopic color video and associated per-pixel depth information. From these data, one or more "virtual" views of a real-world scene can be synthesized in real-time at the receiver side (i.e. a 3D-TV set-top box) by means of so-called depth-image-based rendering (DIBR) techniques. This publication will provide: (1) a detailed description of the fundamentals of this new approach on 3D-TV; (2) a comparison with the classical approach of "stereoscopic" video; (3) a short introduction to DIBR techniques in general; (4) the development of a specific DIBR algorithm that can be used for the efficient generation of high-quality "virtual" stereoscopic views; (5) a number of implementation details that are specific to the current state of the development; (6) research on the backwards-compatible compression and transmission of 3D imagery using state-of-the-art MPEG (Moving Pictures Expert Group) tools.
Depth perception in images and video has been a relevant research issue for years, with the main focus on the basic idea of "stereoscopic" viewing. However, it is well known from the literature that stereovision is only one of the relevant depth cues and that motion parallax, as well as color, brightness and geometric appearance of video objects are at least of the same importance - with the individual influence being mainly dependent on the object distance. Thus, for depth perception it may sometimes be sufficient to watch pictures or movies on large screens with brilliant quality or to provide head-motion parallax viewing on conventional 2D displays. Based on this observation we introduce an open, flexible and modular immersive TV system that is backwards-compatible to today's 2D digital television and that is able to support a wide range of different 2D and 3D displays. The system is based on a three-stage concept and aims to add more and more depth cues at each additional layer.
In this paper we will present the concept of a modular three dimensional broadcast chain, that allows for an evolutionary introduction of depth perception into the context of 2D digital TV. The work is performed within the framework of the European Information Society Technologies (IST) project "Advanced Three-dimensional Television System Technologies" (ATTEST), bringing together the expertise of industries, research centers and universities to design a backwards-compatible, flexible and modular broadcast 3D-TV system. This three dimensional broadcast chain includes content creation, coding, transmission and display. Research in human 3D perception will be used to guide the development process.
The goals of the project towards the optimized 3D broadcast chain comprise the development of a novel broadcast 3D camera, algorithms to convert existing 2D-video material into 3D, a 2D-compatible coding and transmission scheme for 3D-video using MPEG-2/4/7 technologies and the design of two new autostereoscopic displays.