Multichannel Audio Transmission over IP Network by MPEG-4 ALS and Audio Rate Oriented Adaptive Bit-rate Video Codec
Yutaka Kamamoto, Noboru Harada, Takehiro Moriya, Sun Yong Kim, Takahiro Yamaguchi, Masanori Ogawara, Tatsuya Fujii · NTT technical review · 2013
This article describes an experiment of lossless audio transmission over an Internet protocol (IP) network and introduces a prototype codec that combines lossless audio coding and variable bit rate video coding.In the experiment, 6-channel acoustic signals compressed by lossless audio coding (MPEG-4 Audio lossless coding (ALS) standardized by the Moving Picture Experts Group) were transmitted from a live venue to a café via the IP network.At the café, received sound data were decoded losslessly and then appropriately remixed to adjust to the environment at that location.The combination of highdefinition video and audio data enables fans to enjoy a live musical performance in places other than the live venue.This experiment motivated us to develop a new prototype codec that guarantees high audio quality.The developed codec can control the bit rates of both audio and video signals jointly, and it achieves high audio and video quality.* The moving picture experts group (MPEG) is a working group of international organization for standardization (ISO) and the international electrotechnical commission (IEC) that develops standards for coded representation of digital audio and video and related data.