What is considered a “good” PQR score?

A “good” picture quality score depends greatly on the system being tested. Ideally, a PQR score of 0 is perfect, but one would only ever see a score that low with a very high quality SDI loop through. Any composite video will likely see a score of 3 to 4 on a high quality loop through from the NTSC/PAL conversion alone.

As a general rule of thumb, a PQR score of 1 is considered to show little or no perceived impairment. A score of 3 would show some impairment, but it would not be very strong. A score of 10 or more would shoe clearly observable impairment.

For a high quality MPEG encoder/decoder system, one might expect to see PQR values ranging from 3 to 14 roughly corresponding to bit rates of 12Mbps to 3Mbps.

For more information on PQR scores, see our application note "Measuring and Interpreting Picture Quality in MPEG Compressed Video Content", available from the following link:

Application Note