Assessing packet loss visibility in video

The invention presents a new NR-H method for assessment of packet loss visibility measure for a video sequence, where the measure is indicative of the effect on the perceptual quality of the video. Packet loss can occur as a result of the video being transmitted over an imperfect network. The invention combines dynamic modelling of temporal and spatial properties of the decoded pictures with bitstream information revealing location, extent and propagation of any errors. Analysis is performed on blocks of pixels, and preferably the macroblocks defined in the particular video encoding scheme. Knowledge of the error extent from the bitstream information is used to target spatial analysis around the specific error locations. Perceptual impact is estimated by utilizing spatio-temporal modelling to predict the properties of a missing block, and comparing those predictions with the actual properties of the missing block.