Accession Number:

ADA257242

Title:

Subjective Tests of Teleconferencing CODECS

Descriptive Note:

Final rept.

Corporate Author:

DELTA INFORMATION SYSTEMS INC HORSHAM PA

Personal Author(s):

Report Date:

1991-01-01

Pagination or Media Count:

60.0

Abstract:

This report describes the results of subjective evaluation of teleconferencing codecs. Preliminary tests used a previously developed test tape simulating typical teleconferencing applications which resulted in a quality rating of each bit rate for the selected applications. Later tests emphasized motion performance using the more recently developed Video Codec Test Tapes Limited Motion and Full Motion. These tapes were taken to the location of each manufacturer and fed into the codec to be tested. The manufacturer then could certify that this codec was in proper operation condition. The codecs were connected back-to-back and processed output tapes obtained at 64, 128, 256, 384, 768, and 1536 or 1544 Kbps, in each case covering the full operating range of the codec. The processed tapes were viewed and rated in terms of picture impairment by a group of impartial evaluators. The test scores obtained from all evaluators were analyzed and finally correlated with previously obtained initial objective test results. Teleconferencing codecs, Video Codec.

Subject Categories:

  • Cybernetics
  • Radio Communications
  • Non-Radio Communications

Distribution Statement:

APPROVED FOR PUBLIC RELEASE