MPEG-2 real-time software CODEC for full-duplex transmission application over IP networks

This paper proposes a real-time MPEG-2 software CODEC for full-duplex transmission applications, and evaluates its performance and usefulness. The CODEC consists of a high-speed encoder/decoder, an IP sender/receiver, and an error recovery controller. Each encoder/decoder is accelerated and optimized by exploiting fast algorithms and instruction-level parallelism. The IP sender/receiver combination achieves low delay owing to the direct translating of each elementary stream of video and audio into UDP/IP packets. The error recovery controller carries out simple but powerful error tolerance against packet loss over IP networks. This CODEC attains low delay of 99 ms (M = 1, N = 1) to 165 ms (M = 3, N = 3) including input, encoding, transmitting, decoding, and output delays, and maintains a normal frame rate of 30 fps (frames per second) and more than 20 fps even under a fairly heavy network load. It provides sufficiently good performance for use as a real-time full NTSC-size CODEC on a PC of at least 1.2-GHz CPU.