What is DSCQS?

DSCQS stands for Double Stimulus Continuous Quality Scale. It is an ITU scale of 0 -100 based on studies with human observers who watched and participated in video quality measurement from two sources. One showed the video without any transmission errors (i.e. the reference, or source material), the other showed the same video material after alteration by transmission errors. The observers assessed the video quality by direct comparison, evaluating the quality of the video by moving the slider of a handheld voting device.

Video quality measurement has traditionally been performed by human observers. Known as DSCQS, this method has been standardized under ITU-R (International Telecommunications Union-Recommendation) BT-500. Under this method, picture quality is expressed as a percent from 0 to 100, with 0 indicating no distortion. The higher the value, the greater the distortion between the original and the tested video images.

While DSCQS provides a good index for video quality evaluation, this method requires not only a special testing room, monitors, and video editing but also a panel of 15 or more human observers. Inevitably, this type of testing has various limitations such as the inability to reproduce consistent results and conduct "real-time" video quality evaluation as well as the difficulty in conducting extended testing. With K-WILL's technology it becomes easy to automate this process.