Witbe measures global quality of digital TV at 2.9 out of five

December 1, 2008 - French monitoring firm Witbe has conducted a study of digital standard-definition services (delivered via DSL, cable, FTTH, satellite and DTT) with 30 operators in 16 countries across four continents, and found an average worldwide video quality rating of 2.9 out of five.

The worldwide average was measured using Witbe's VideoMOS algorithm and the firm found that the measurement was affected by a number of factors, including: encoding policies, as telcos have to increase the compression ratio of the video to increase the number of eligible customers; the broadcasting technology, with cable video found to be less pixelated than IPTV, as it experiences less transmission problems such as packet loss; the maturity of the service, as many of those launched recently often have lower availability (black screens, error messages, channel change issues etc) and have poorer quality; interoperability issues between CA, middleware and STB; and the presence of intelligent retransmission mechanisms or forward error correction.

A similar study of Asian video quality, conducted in Taiwan, Hong Kong and Singapore, found a rating of 3.1 out five, the same as that measured in the French market, where all IPTV operators are customers of Witbe.

Another study carried out by Witbe on high-definition digital TV services found that users perceive different video artefacts, as an HD picture is usually less blocky and sharper than an SD picture, however HD encoding policies are more sensitive to network issues than SD video. The firm also notes that not all high-definition programmes are equal - some broadcasts upscaled to HD show a much higher blur than broadcasts in native HD.