The paper deals with AVC, HEVC and VVC video encoder modeling using a universal formula for the output bitrate as a function of the quantization step. It is shown that this model is relatively accurate and may be used for bitrate control. Moreover, from the model for AVC, the models for HEVC and VVC can be quickly derived, thus reducing the processing time needed for VVC model parameters derivation. The model is applicable to multiview plus depth video coding, both using simulcast and MV-HEVC or 3-D HEVC. The applications to bitrate control for coding of multiview plus depth video are considered together with the relevant experimental data.

In the paper we investigated the methods of obtaining high-resolution, high frame-rate virtual views based on low frame-rate cameras for applications in high-performance multiview systems. We demonstrated how to set up synchronization for multiview acquisition systems to record required data and then how to process the data to create virtual views at a higher frame rate, while preserving high resolution of the views. We analyzed various ways to combine time frame interpolation with an alternative side-view synthesis technique which allows us to create a required high frame-rate video of a virtual viewpoint. The results prove that the proposed methods are capable of delivering the expected high-quality, high-resolution and high frame-rate virtual views.

Virtual reality, free-viewpoint television, virtual navigation, 360° video are the areas of research and technology that need efficient compression of multiview video plus depth acquired by cameras with arbitrary positions. Astonishingly, proliferation of 3D extensions of AVC and HEVC technology is very low. Therefore, in this paper, we present a study on independent coding of views and depth maps. A simple technique is proposed to estimate quantization step for depth as a function of the quantization step for multiview video. This technique is studied in the context of multiview video plus depth acquired using cameras located around a scene. The approach is based on simple modeling of the relation between quantization parameters for depth and multiview video. The experimental results are obtained for stereoscopic video with two respective depth maps. For standard MPEG test sequences, the results demonstrate usefulness of the approach for HEVC, VVC, MV-HEVC codecs.

In this paper we present a novel method for depth estimation from stereoscopic 360-degree video. As for now, no such methods have been presented in the literature. First we show mathematical foundations for correspondence matching polar coordinates. Then, the attained formulas are simplified to show relationship to depth estimation in rectified pairs of rectangular images. The proposed method has been implemented in Depth Estimation Reference Software (DERS) developed by Motion Picture Experts Group (MPEG) of International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC). Finally, we present experimental results in form of depth maps estimated for “Dancing 360” stereoscopic omnidirectional sequence.

The demonstration is aimed at presenting a simple free-viewpoint television system that is under development at Poznań University of Technology, Poznań, Poland. Video acquisition using sparsely distributed pairs of video cameras, the depth estimation from video, the virtual video rendering on a server feature the perspective FTV system. The original depth estimation and view synthesis algorithms ensure good quality of the virtual views generated during virtual walks around a scene. The system is developed for broadcasting sport (e.g. judo, karate, volleyball) and cultural (e.g. amateur or professional theater performances) events, as well as for interactive courses and manuals (medical, cosmetics, dancing, technical etc.).

The paper presents the concept of a practical free-viewpoint television system with purely optical depth estimation. The system consists of camera modules that contain pairs or triples of cameras together with the respective microphones. The camera modules can be sparsely located in arbitrary positions around a scene. Each camera module is equivalent to a video camera with a depth sensor and microphones. The hardware requirements, the video and audio processing algorithms and the preliminary experimental results are reported. In particular, for such systems, a compression technique is discussed that is more efficient than the new 3D-HEVC technology. A set of new test sequences obtained with the use of camera pairs are presented.

Rate-Distortion Optimized Quantization (RDOQ) is an encoding optimization technique that may be modified with no implications to the bitstream compliance with the standard. In the paper, we propose an RDOQ variant with exact cost estimation resulting in higher compression ratios as compared to HEVC Test Model. This improvement is obtained at the cost of the complexity increase that may be scaled by replacing the individual steps of exact estimation by the simplified ones from HEVC Test Model. In that way, a family of RDOQ variants is created. The performance of the exact variant from this paper defines a kind of the performance limit for RDOQ.

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.

A computationally inexpensive watermark schema for MPEG-4 AVC/H.264 streams that use local mark strength adjustment minimizing visible artifacts is presented. The local mark strength adjustment mechanism and watermark embedding mechanism operate on residual data. This approach minimize the number of operations needed for video bitstream decoding and subsequent watermarked video data encoding. The experimental results included herein, described for real-world MPEG4 AVC/H.264 encoded HDTV video bitstreams prove its robustness to complex attacks, especially camcorder recording attack.

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.

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.

The paper describes watermarking of compressed video bitstreams. This technique is proven to be very fast and robust against various attacks including camcorder recording attack. The watermark is embedded using indirect modifications of transform coefficients in selected P- and B-frames. In the watermarked bitstream there exist sequences of watermarked pictures interleaved with sequences of unmodified pictures. The unmodified pictures serve as a reference for the watermark detection. The experimental results described for real-world MPEG-4 AVC/H.264 encoded HDTV video bitstreams are included.

For MPEG-4 AVC/H.264 video encoders, the paper describes a model that defines a relationship between the number of bits for texture information and the quantization step size Q. The model is derived individually for I-, P- and B-frames. The model is defined by formulas given individually for 3 intervals covering whole eligible range of Q values. Extensive experiments with numerous test video sequences have proved good accuracy of the model proposed. In particular the new model exhibits higher accuracy than that from the reference implementation of AVC.

For AVC/H.264 video encoders, the paper describes a simple global model that defines a relationship between the bitrate and the quantization step Qstepfor I-, P- and B-frames. Proposed is a general model for any video shot. As such a model must be dependent on video content, the model parameters have to be estimated from experimental data individually for each video shot, and individually for each frame type. The model is defined by formulas given individually for 3 intervals covering whole eligible range of Qstepvalues. Extensive experiments with numerous test video sequences have proved good accuracy of the model proposed.