  A novel Key Quality Indicator for video delivery applications, XLR (piXel
Loss Rate), is defined, characterized, and evaluated. The proposed indicator is
an objective measure that captures the effects of transmission errors in the
received video, has a good correlation with subjective Mean Opinion Scores, and
provides comparable results with state-of-the-art Full-Reference metrics.
Moreover, XLR can be estimated using only a lightweight analysis on the
compressed bitstream, thus allowing a No-Reference operational method.
Therefore, XLR can be used for measuring the quality of experience without
latency at any network location. Thus, it is a relevant tool for network
planning, specially in new high-demanding scenarios. The experiments carried
out show the outstanding performance of its linear-dimension score and the
reliability of the bitstream-based estimation.
