The monitoring of the service quality is crucial to the successful operation of commercial internet services to end customers. Services such as IPTV, which require high available bandwidth, low latency and few transmission errors, are especially sensitive to network congestions.
Video quality measurements methods are often divided into three groups, full reference, reduced reference, and no reference, depending on how much of the reference or the original is available or needed by the method. The standard for video quality (image-only) measurements by the International Telecommunication Union (ITU) covers full reference methods for standard definition TV e.g. (ITU-T, 2004). However, the standard covers four different methods, making it possible to measure with standardised methods and still come to different results.