Abstract: Systems and methods are described for determining a set of three quality metrics for audio and/or video signals transmitted through a packet network. The set of three metrics provide more insight into which factors are affecting the quality of the received signal as perceived by the end-user. These three quality metrics measure reductions in quality due to lossy media transmission, packet loss concealment from packet loss and/or packet/frame jitter, and long periods of silence and/or frozen video. Because each metric quantifies a different aspect of transmitted quality, a deficiency in the transmitted signal can be identified by reference to the set.

Abstract: The present invention relates to the problem of estimating the effect of packet transmission impairments, including packet loss, on the subjective quality of a video transmission where frames of data relating to the same video frame or field are permitted to span more than one packet. The invention provides a method of assessing quality of a video signal comprising a sequence of video frames received via a packet switched network using a parameter which is a weighted sum of two counters where the first counter is incremented in dependence of the total number of packets in frames determined to have been received with one or more lost packets and the second counter is incremented in dependence of the number of packets following the first lost packet in each frame and the lost packet itself.

Abstract: This invention relates to a non-intrusive video quality assessment system. A method and apparatus are provided in which video frame parameters are extracted from a sequence of packets by generating a first video quality parameter for each group of packets associated with a particular frame of video data in dependence upon the frame rate of the video stream; and generating a second video quality parameter for each of said group of packets in dependence upon the size of encoded data comprising the video frame.

Abstract: The present invention relates to the problem of estimating the effect of packet transmission impairments, including packet loss, on the subjective quality of a video transmission where frames of data relating to the same video frame or field are permitted to span more than one packet. The invention provides a method of assessing quality of a video signal comprising a sequence of video frames received via a packet switched network using a parameter which is a weighted sum of two counters where the first counter is incremented in dependence of the total number of packets in frames determined to have been received with one or more lost packets and the second counter is incremented in dependence of the number of packets following the first lost packet in each frame and the lost packet itself.

Abstract: This invention relates to a non-intrusive video quality assessment system. A method and apparatus are provided in which video frame parameters are extracted from a sequence of packets by generating a first video quality parameter for each group of packets associated with a particular frame of video data in dependence upon the frame rate of the video stream; and generating a second video quality parameter for each of said group of packets in dependence upon the size of encoded data comprising the video frame.