Remote Media Immersion (RMI)

The Remote Media Immersion (RMI) system is the result of a unique blend of multiple cutting-edge media technologies to create the ultimate digital media delivery platform. The main goal is to provide an immersive user experience of the highest quality. RMI encompasses all end-to-end aspects from media acquisition, storage, transmission up to their final rendering. Specifically, the Yima streaming media server delivers multiple high bandwidth streams, transmission error and flow control protocols ensure data integrity, and high-definition video combined with immersive audio provide highest quality rendering. The RMI system is operational and has been successfully demonstrated in small and large venues. Relying on the continued advances in electronics integration and residential broadband improvement, RMI demonstrates the future of on-demand home entertainment.

INTRODUCTION

The charter of the Integrated Media Systems Center (IMSC) at the University of Southern California (USC) is to investigate new methods and technologies that combine multiple modalities into highly effective, immersive technologies, applications and environments. One of the results of these research efforts is the Remote Media Immersion (RMI) system. The goal of the RMI is to create and develop a complete aural and visual environment that places a participant or group of participants in a virtual space where they can experience events that occurred in different physical locations. RMI technology can effectively overcome the barriers of time and space to enable, on demand, the realistic recreation of visual and aural cues recorded in widely separated locations.

The focus of the RMI effort is to enable the most realistic recreation of an event possible while streaming the data over the Internet. Therefore, we push the technological boundaries much beyond what current video-on-demand or streaming media systems can deliver. As a consequence, high-end rendering equipment and significant transmission bandwidth are required. The RMI project integrates several technologies that are the result of research efforts at IMSC. The current operational version is based on four major components that are responsible for the acquisition, storage, transmission, and rendering of high quality media.

STAGES OF RMI

Acquisition of high-quality media streams

This authoring component is an important part of the overall chain to ensure the high quality of the rendering result as experienced by users at a later time. As the saying “garbage in, garbage out” implies, no amount of quality control in later stages of the delivery chain can make up for poorly acquired media.

Real-time digital storage and playback of multiple independent streams

Yima Scalable Streaming Media Architecture provides real-time storage, retrieval and transmission capabilities. The Yima server is based on a scalable cluster design. Each cluster node is an off-the-shelf personal computer with attached storage devices and, for example, a Fast or Gigabit Ethernet connection. The Yima server software manages the storage and network resources to provide real-time service to the multiple clients that are requesting media streams. Media types include, but are not limited to, MPEG-2 at NTSC and HDTV resolutions, multichannel audio (e.g., 10.2 channel immersive audio), and MPEG-4

Protocols for synchronized, efficient real time transmission of multiple media streams

A selective data retransmission scheme improves playback quality while maintaining realtime properties. A flow control component reduces network traffic variability and enables streams of various characteristics to be synchronized at the rendering location. Industry standard networking protocols such as Real-Time Protocol (RTP) and Real-Time Streaming Protocol (RTSP) provide compatibility with commercial systems.

Rendering of immersive audio and high resolution video

Immersive audio is a technique developed at IMSC for capturing the audio environment at a remote site and accurately reproducing the complete audio sensation and ambience at the client location with full fidelity, dynamic range and directionality for a group of listeners (16 channels of uncompressed linear PCM at a data rate of up to 17.6Mb/s). The RMI video is rendered in HDTV resolutions (1080i or 720p format) and transmitted at a rate of up to 45 Mb/s.