Table 1 Summary of conditions of all databases

Number of sequences

Total 78, 6 different source sequences

Total 45, 9 different source sequences in compressed and uncompressed formats

Total 170, 10 different source sequences

Resolution

4CIF (704 × 576)

1,920 × 1,080

768 × 480

Duration

10 and 8 s

10 s

10 s

Reference

Compressed (with high quality)

Compressed (with high quality) and uncompressed

Compressed (with high quality)

Compression parameter

Fixed QP between 28 and 32

Fixed QP value 26

Reference video: Fixed QP value 18

Degraded videos: bitrates 500 kbps, 1 Mbps, 1.5 Mbps and 2 Mbps

I-frame period

Not available

24 frames

Reference video: 14 frames

Degraded videos: 96

Frame rate

25 and 30 fps

59,94 (interlaced) fps

30 fps

Transmission distortions

PLR 0.1%, 0.4%, 1%, 3%, 5%, 10%. Two different channel realizations for each PLR

PLR 0.7% (from 42% to 56% of the way), 4.2% (from 21% to 64% of the way), 4.2% (from 42% to 56% of the way).

PLR 0.5%, 2%, 5% and 17%

Encoder/decoder

H.264/AVC JM reference software

Not available

H.264/AVC JM reference software

Number of subjects

21 at PoliMI lab and 19 at EPFL lab

24

31

Processing of subjective scores

Difference scores → Z-scores (with outliers detection) → re-scaling to range [0,5] → DMOS

Difference scores → Z-scores (with outliers detection) → re-scaling to range [0,5] → DMOS both for compressed and uncompressed reference

Difference scores → DMOS → re-scaling to range [0,5]