Yongwoo Cho

True realtime multimedia streaming system based on MMT

MPEG Media Transport(MMT) has being standardized in SC29/WG11 MPEG as a next generation media transport in all IP environments. This paper proposed a true-realtime system based on MMT features. This true-realtime system minimizes the delay between generation of a content in the server and display in the client within 10s ms if there is no network jitter. This paper includes object and temporal design of the system.

Scalable video streaming over TV white spaces using Cognitive Radio technology

The objective of this paper is to provide uninterrupted scalable video streaming to the Cognitive Radio (CR) users by transmitting video frames over multiple channels in hybrid overlay and underlay modes. Since the underlay model is characterized by low power and low bitrate, I-frames of the base layer is an attractive solution. Our contribution is to rank the available spectrum bands based on some parameters such as packet loss, channel capacity, delay, and jitter. Then, the base layer frames as well as the enhancement layer(s) are transmitted without interruption over available high rank spectrum bands. By continues spectrum monitoring, the system creates a descending ranked list of available channels. At the time of arrival of incumbents, the system checks the list and switches to another available spectrum band even with lower rank. Whereas, the I-frames have higher priority, if there is no more channel with acceptable quality, then the I-frames are transmitted in underlay mode. Our simulation results show that the quality of the received video is guaranteed by assuring of I-frame streaming in hybrid mode in compare to pure overlay mode.

A 3D model-based multi-camera monitoring system for panoramic video

This paper proposes multi-camera monitoring system that relies on 3D views for panoramic video. The proposed system monitors the projected 3D model view, instead of individual 2D views, to detect image distortions. This can minimize compensation errors caused by parallax, thereby improving the quality of the resulting panoramic video.

MMT-based QoS adaptive video service

MPEG published a new international standard, MMT (MPEG Media Transport) for efficient transport of MPEG media over all IP networks in June 2014. This paper shows its potential as standard for adaptive media service system. We applied this standard to video streaming system and shows its efficiency transmission in limited resource network environment. The system has been tested in harsh condition such as simulated mobile channels.

High resolution video streaming method by cloud and DASH

This paper presents that video files encoded to patch are transferred to number of nodes over a cloud at the same time. The download speed of client can be improved by using distributed links via DASH of cloud nodes. Client can receive the stream like bandwidth improvement of P2P architecture.

LDPC based distributed video coding with multiple side information sets

The side information (SI) used to decode the original frame in the distributed video coding (DVC) is created by a key frame encoded by an existing video codec. This paper proposes a method to restore the original frame using the characteristics of multiple sets of SI and low-density parity-check (LDPC) code. It was identified that the optimal SI could be made by combining multiple sets of SI restored through repeated decoding of SI and LDPC that the SI could be restored to be the closest to the original frame using the optimal SI.