Robert Ratajczak

High Efficiency 3D Video Coding Using New Tools Based on View Synthesis

We propose a new coding technology for 3D video represented by multiple views and the respective depth maps. The proposed technology is demonstrated as an extension of the recently developed high efficiency video coding (HEVC). One base views are compressed into a standard bitstream (like in HEVC). The remaining views and the depth maps are compressed using new coding tools that mostly rely on view synthesis. In the decoder, those views and the depth maps are derived via synthesis in the 3D space from the decoded baseview and from data corresponding to small disoccluded regions. The shapes and locations of those disoccluded regions can be derived by the decoder without any side information transmitted. To achieve high compression efficiency, we propose several new tools such as depth-based motion prediction, joint high frequency layer coding, consistent depth representation, and nonlinear depth representation. The experiments show high compression efficiency of the proposed technology. The bitrate needed for transmission of two side views with depth maps is mostly less than 50% than that of the bitrate for a single-view video.

Coding of multiple video+depth using HEVC technology and reduced representations of side views and depth maps

During the last two decades, a new technology generation of video compression was introduced about each 9 years. Each new compression-technology generation provides halving of necessary bitrates as compared to the last previous generation. This increasing single-view compression performance is related to increasing compression performance of multiview video coding. For multiview video with associated depth maps, additional significant bitrate reduction may be achieved. The paper reports the original compression technology that was designed and developed at Poznań University of Technology in response to MPEG Call for Proposals on 3D Video Coding Technology. The main idea of this technique is to predict very efficiently the side views and the depth maps from the base view.

3D video compression by coding of disoccluded regions

In this paper, we present the most efficient coding tools that are used in a new video compression technology for multiple views with the depth maps. This very well performing technology was designed and developed in response to MPEG Call for Proposals on 3D Video Coding Technology. The proposed technology exploits a tool that reduces the side views and the side depth maps to small disoccluded regions. This way only one central view and one depth map are coded in the HEVC syntax while the remaining views and the depth maps are synthesized in the decoder from the small disoccluded regions and from the central-view data. Therefore, the bitrate needed for a side view is mostly below 20% of the bitrate for single-view video.

Vehicle dimensions estimation scheme using AAM on stereoscopic video

Recently, stereoscopic video systems are studied in the context of many new applications. This paper addresses the question how the road traffic surveillance may benefit from stereoscopic video analysis. In particular, we propose a novel method for estimating vehicle dimensions using stereoscopic video analysis. This method is based on active appearance model (AAM), a technique already used, e.g. for face detection. Experimental results are provided in the paper in order to demonstrate satisfactory precision of the measurements.

Methods of high efficiency compression for transmission of spatial representation of motion scenes

The paper reports the hitherto obtained results of the research project that deals with scene representations that are suitable for free navigation around the scene. These scene representations are acquired from a limited number of cameras located around the scene. The project is aimed at the development of an efficient compression technology and the experimental environment for testing such technology. The paper reports some new multiview test sequences with the circular camera arrangement, including the hybrid ones that have been acquired using also the depth sensors. Finally, the paper also briefly reports the recent results of the new compression technology being under development. This technology outperforms the state-of-the-art 3D-HEVC.

Limitations of vehicle length estimation using stereoscopic video analysis

In the paper vehicle length estimation based on stereoscopic video analysis is considered. The accuracy of the parameters of the stereoscopic video acquisition system influence accuracy of the estimated vehicle length. The respective analysis is provided in the paper. The main result is the formula for estimating the accuracy of the vehicle length measurement.