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The point cloud is a medium that visualizes various information by placing a point having a color value and a geometry value in a three-dimensional space. The point cloud uses dozens and millions of points for visualization of information, and the key point of commercialization of this point cloud video is to efficiently compress a large amount of information of point cloud and transmit it to users. Currently, MPEG V-PCC is conducting dynamic point cloud compression research using the 2D video codec, where motion estimation is conducted in terms of 2D video sequences. Thus, there is a limitation in estimating the motion in 3D point cloud contents. In this paper, we propose the method to use the 3D motion for point cloud video compression. The proposed technology achieves efficient compression rate and improves accuracy in lossy compression.

Recently, the emergence of 3D cameras, 3D scanners and various cameras including Lidar is expected to promote various 3D media applications such as AR, VR and autonomous mobile vehicles. The 3D media can be recently realized by not only 2D pixel and depth information but also points with texture and geometry information. In particular, 3D point cloud data is consisted of hundreds of thousands to millions of 3D points, and thus dramatically increases its data size compared to 2D media data, which brings up the development of an efficient encoding/decoding technology. Also, it is required to develop a scalability function such as Level of Detail (LoD) for both an effective service with different bandwidths, devices and Region of Interest (RoI). In this paper, we propose a new LoD quality parameter considering characteristics of 3D point cloud contents instead of bitrate change based on a video codec in MPEG Video-based Point Cloud Compression (V-PCC). Therefore, the use of LoD table proposed in this paper is confirmed to generate 3D point cloud contents with different point density.

A lot of 3D contents haven been widely used for multimedia services, however, real 3D video contents have been adopted for a limited applications such as a specially designed 3D cinema. This is because of the difficulty of capturing real 3D video contents and the limitation of display devices available in a market. However, diverse types of display devices for stereoscopic video contents for real 3D video contents have been recently released in a market. Especially, a mobile phone with a stereoscopic camera has been released in a market, which provides a user as a consumer to have more realistic experiences without glasses, and also, as a content creator to take stereoscopic images or record the stereoscopic video contents. However, a user can only store and display these acquired stereoscopic contents with his/her own devices due to the non-existence of a common file format for these contents. This limitation causes a user not share his/her contents with any other users, which makes it difficult the relevant market to stereoscopic contents is getting expanded. Therefore, this paper proposes the common file format on the basis of ISO base media file format for stereoscopic contents, which enables users to store and exchange pure stereoscopic contents. This technology is also currently under development for an international standard of MPEG as being called as a stereoscopic video application format.

This paper introduces an interactive contents authoring system which can easily and conveniently produce interactive contents for the Terrestrial Digital Multimedia Broadcasting (T-DMB). For interactive broadcasting service, T-DMB adopted MPEG-4 Systems technology. In order to the interactive service becomes flourishing on the market, various types of interactive contents should be well provided prior to the service. In MPEG-4 Systems specification, broadcasting contents are described by the combination of a large number of nodes, routes and descriptors. In order to provide interactive data services through the T-DMB network, it is essential to have an interactive contents authoring system which allows contents authors to compose interactive contents easily and conveniently even if they lack any background on MPEG-4 Systems technology. The introduced authoring system provides powerful graphical user interface and produces interactive broadcasting contents in the forms of binary and textual format. Therefore, the interactive contents authoring system presented in this paper would vastly contribute to the flourishing interactive service.

This paper describes issues and consideration on authoring of 3D visual content based on MPEG-4 Systems. The issues include types of 3D visual content; functionalities for user-interaction; 3D scene composition for rendering; and the 3D visual content file format. MPEG-4 includes several extensions compared to MPEG-1 and -2 especially in terms of object-based interactivity. In addition to advanced A/V compression methods (MPEG-4 Part2, Part3 and Part 10), MPEG-4 Part1, which is named "Systems", contains additional tools such as binary/textual file format, multiplexing, synchronization scheme, scene description, etc. The use of MPEG-4 can resolve the problem of format diversity while providing high interactivity to users. There has been little investigation on 3D visual content authoring. Throughout the paper, we will present which issues need to be determined and how currently available tools can be effectively utilized for 3D visual content creation.

In this paper, we present an effective streaming method for MPEG-4 contents using the schedule information of image objects and progressive JPEG. The proposed method is designed for Interactive Scalable Multimedia Streaming (ISMuS) system. In rich interactive contents, the amount of image objects is not negligible for a streaming service with QoS. If a streaming system does not manage the image data, it could create a bottleneck in the system. The proposed method considers the schedule information of image objects to be displayed within a specific time frame, generally within a few second. Since the proposed method uses the progressive JPEG instead of Baseline JPEG, it treats image object as scalable Object. The streaming server sends surely DC data of each image object and AC data of image object is sent only when there is an enough room for AC data in network bandwidth. The priorities of audio and video elementary stream are also within the consideration as well as those image objects according to the varying network status.

Within the last years, the enormous growth of Internet based communication as well as the rapid increase of available processing power has lead to the widespread use of multimedia streaming as a means to convey information. This work aims at providing an open architecture designed to support scalable streaming to a large number of clients using application layer multicast. The architecture is based on media relay nodes that can be deployed transparently to any existing media distribution scheme, which can support media streamed using the RTP and RTSP protocols. The architecture is based on overlay networks at application level, featuring rate adaptation mechanisms for responding to network congestion.

In this paper, we present an MPEG-4 contents streaming system and propose MPEG-4 contents streaming scheme by using priority. The presented streaming system which consists of a server and a client supports MPEG-4 contents compliant with ISO/IEC 14496-1 and enables a user to interact with MPEG-4 contents over IP networks. The server consists of GUI, Server Management Layer, Sync Layer, and Delivery Layer. The client supports to display MPEG-4 contents stored in local storage or received through IP networks. Moreover, we propose an MPEG-4 contents streaming scheme that the object a user prefers to watch is sent first by increasing priority and objects with low priority are dropped at a server side when network bandwidth is not enough to transmit all objects that are supposed to appear in the scene. We made experiment of the proposed scheme with the presented MPEG-4 contents streaming system, and the experiment results are shown in this paper. If we use the proposed scheme for MPEG-4 contents streaming, it is possible for a user to watch a video of interest in high quality and video of indifference in low quality.