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This report describes an inexpensive system for transmitting production quality television over IP-based networks using RTP. The software system, called RTPtv, can send audio and video streams using the IETF RTP standard for media streaming using either multicast or unicast transmission.
The RTPtv system can be used to send and receive various quality streams. The production TV quality streams send video as 60 field/sec, full-sized 4:2:2 video images compressed with motion-jpeg and send audio as stereo 16-bit PCM audio sampled at 44 KHz. The video and audio transmission bandwidths are 10-20 Mbs and 1.4 Mbs, respectively. The receiver decodes and plays the video and synchronized audio. The video output can be played either on a TV monitor or as an overlay window on a computer screen. The quality of this full-sized production quality transmission is indistinguishable from conventional broadcast television. RTPtv can also be used to produce a lower bit rate transmission. A video transmission with 30 frame/sec, CIF-sized 4:2:2 video images can be sent at 5 Mbs and an audio transmission with mono 16-bit PCM audio sampled at 16 KHz can be sent at 256 Kbs.
This report presents detailed explanations of the techniques used to maintain synchronization of audio and video over extended periods of time and to conceal packet loss within the network.
The hardware required to send/receive RTPtv streams is an inexpensive Linux PC with a particular video capture card that has a hardware jpeg encoder/decoder. Total cost for the computer and audio/video hardware is roughly $1.5K. Details on the hardware and the software are given in the report and on the web pages referenced below.
More information about this technology is available at: