Technical evaluation of a low-bandwidth, Internet-based system for teleconsultations

A low-bandwidth telemedicine system was evaluated in eight community hospitals connected to a central hospital via the Internet. PCs were used with videoconferencing software and modem connections to the telephone network. The average data connection rates, still-image transfer times and live-video transmission rates were determined. The time to send 640x480, 320x240 and 160x120 pixel, 24-bit still images ranged from 29 s to 411 s. The average file transfer times for a 10 s MPEG video-clip was 8.6 min. The average live video frame rate was 1 frame/s (at the best image quality), with an average latency of 3 s. The results suggest that Internet-based videoconferencing is acceptable for certain telemedicine applications.