Subjective Assessment of Video Quality (MSU PVQ tool)

Contact person: Dmitriy S. Vatolin (dmitriy@graphics.cs.msu.ru)

Methods of subjective video quality assessment

Motivation

Evaluation of the video quality is an important task in the area of video processing. Often quality is required to be measured automatically (without human’s interference), and this goal is achieved with objective metrics. However, objective metrics can only serve as an estimation of the real quality of video, which is the subjective opinion of actual viewers. Our research is aimed at methods of subjective video quality assessments and evaluation of objective quality metrics.

Approach

During last years a number of subjective testing methodologies were suggested, some of them were standardized. Because of the lack of tools for conducting subjective tests in the public domain, we created MSU Perceptual Video Quality tool. It implements following testing methodologies:

  • DSIS
  • DSCQS type I and II
  • SCACJ
  • SAMVIQ
  • MSU CQE

They were implemented according to the standard ITU-R BT.500-11 “Methodology for the subjective assessment of the quality of television pictures”, in addition their description can be found in tool’s documentation.

We developed new MSU CQE method. It implements an idea of continuous quality evaluation: user is "voting" against a sequence byu clicking on it. Such scheme is stated to be useful for subjective comparisons of video codecs.

MSU PVQ tool was used for the Subjective Comparison of Modern Video Codecs. Results obtained with this tool were used for the development of new objective metrics.

References

  1. Tool page on www.compression.ru
  2. “Subjective Comparison of Modern Video Codecs”, .pdf (852 kB) .zip (721 kB) 

Team