Appendix 2 - Cisco SX20 - Detailed Video Tests
It was not possible to force either the video or audio protocols in the SX20 CODECs hence we were only able to carry out detailed tests on H.264 video coding. For the following tests using the DVI input and with the PC input set to Motion and the PC selected to the main channel the following video resolutions were negotiated:
|
Objective Video Tests: Signal measurements
- 75% EBU bars
- Grey scale
Subjective Video Impairments Tested: |
|
Lip synchronisation |
LS |
Block distortion (tiling) |
BLK |
Blurring (reduced edge sharpness and spatial detail) |
BLR |
Colour errors |
CLR |
Jerkiness (distortion of smooth motion) |
JRK |
Object persistence (lagging images from previous frames as faded or outline images) |
OP |
Scene cut response (i.e. time to build up the new image) |
SCR |
Scale of impairments:
Imperceptible 1
Perceptible 2
Slightly annoying 3
Annoying 4
Very annoying 5
MII Test Tape:
Signals recorded Time on tape
- EBU colour bars 1min 30secs
- Grey scale 1.40 - 2.40
- Blue field 2.50 - 3.50
- Medium close up female face, still 4.00 - 5.00
- Medium close up female face, talking 5.10 - 6.10
- Close up face, nodding 6.20 - 7.20
- Close up face, shaking head side to side 7.30 - 8.30
- Zoom out slowly to wide angle three people 8.40 - 9.40
- Zoom in quickly to close up of centre person 9.50 - 10.50
- Turntable speeds: 1,2,3 and 4 11.00 - 15.30
- Football sequence 15.40 - 16.40
- Zoom in and out of “A to Z” map 16.50 - 17.50
- Text legibility, font sizes 20 to 12 pt 20.30 - 20.50
- Cut tests, scenes various with camera movements 21.00 - 22.00
- Man teaching at whiteboard 22.10 - 23.23
(Insert 75% EBU bars at local site, measure at remote site)
Test 1 (H264): Colour bar test
(Insert 75% EBU bars at local site, measure at remote site)
Subjective Impairments H.323 |
384 kbit/s |
768 kbit/s |
2 Mbit/s |
4 Mbit/s |
6 Mbit/s |
BLK |
1 |
1 |
1 |
1 |
1 |
BLR |
1 |
1 |
1 |
1 |
1 |
CLR |
1 |
1 |
1 |
1 |
1 |
Test 2 (H.264): Grey scale
(Insert grey scale at local site, measure at remote site)
Subjective Impairments H.323 |
384 kbit/s |
768 kbit/s |
2 Mbit/s |
4 Mbit/s |
6 Mbit/s |
BLK |
1 |
1 |
1 |
1 |
1 |
BLR |
1 |
1 |
1 |
1 |
1 |
CLR |
1 |
1 |
1 |
1 |
1 |
Test 3 (H.264): Blue screen
(Insert blue screen at local site, measure at remote site)
Subjective Impairments H.323 |
384 kbit/s |
768 kbit/s |
2 Mbit/s |
4 Mbit/s |
6 Mbit/s |
BLK |
1 |
1 |
1 |
1 |
1 |
CLR |
1 |
1 |
1 |
1 |
1 |
Test 4 (H.264): Medium close up female (still)
Subjective Impairments H.323 |
384 kbit/s |
768 kbit/s |
2 Mbit/s |
4 Mbit/s |
6 Mbit/s |
BLK |
1 |
1 |
1 |
1 |
1 |
BLR |
2 |
2 |
1 |
1 |
1 |
CLR |
1 |
1 |
1 |
1 |
1 |
Test 5 (H.264): Medium close up female (talking)
Subjective Impairments H.323 |
384 kbit/s |
768 kbit/s |
2 Mbit/s |
4 Mbit/s |
6 Mbit/s |
LS |
1 |
1 |
1 |
1 |
1 |
BLK |
2 |
1 |
1 |
1 |
1 |
BLR |
3 |
2 |
1 |
1 |
1 |
CLR |
1 |
1 |
1 |
1 |
1 |
JRK |
1 |
1 |
1 |
1 |
1 |
Test 6 (H.264): Close up head (nodding)
Subjective Impairments H.323 |
384 kbit/s |
768 kbit/s |
2 Mbit/s |
4 Mbit/s |
6 Mbit/s |
BLK |
2 |
1 |
1 |
1 |
1 |
BLR |
2 |
2 |
1 |
1 |
1 |
CLR |
1 |
1 |
1 |
1 |
1 |
JRK |
1 |
1 |
1 |
1 |
1 |
Test 7 (H.264): Close up head (shaking side to side)
Subjective Impairments H.323 |
384 kbit/s |
768 kbit/s |
2 Mbit/s |
4 Mbit/s |
6 Mbit/s |
BLK |
3 |
3 |
2 |
1 |
1 |
BLR |
3 |
3 |
2 |
1 |
1 |
CLR |
1 |
1 |
1 |
1 |
1 |
JRK |
1 |
1 |
1 |
1 |
1 |
Test 8 (H.264): Medium close up, slow zoom out to three shot
Subjective Impairments H.323 |
384 kbit/s |
768 kbit/s |
2 Mbit/s |
4 Mbit/s |
6 Mbit/s |
BLK |
2 |
1 |
1 |
1 |
1 |
BLR |
2 |
1 |
1 |
1 |
1 |
CLR |
1 |
1 |
1 |
1 |
1 |
JRK |
1 |
1 |
1 |
1 |
1 |
Test 9 (H.264): Three shot, quick zoom in to medium close up centre person
Subjective Impairments H.323 |
384 kbit/s |
768 kbit/s |
2 Mbit/s |
4 Mbit/s |
6 Mbit/s |
BLK |
2 |
1 |
1 |
1 |
1 |
BLR |
2 |
2 |
1 |
1 |
1 |
CLR |
1 |
1 |
1 |
1 |
1 |
JRK |
1 |
1 |
1 |
1 |
1 |
Test 10a (H.264): Turntable speed 1
Subjective Impairments H.323 |
384 kbit/s |
768 kbit/s |
2 Mbit/s |
4 Mbit/s |
6 Mbit/s |
BLK |
2 |
1 |
1 |
1 |
1 |
BLR |
1 |
1 |
1 |
1 |
1 |
CLR |
1 |
1 |
1 |
1 |
1 |
JRK |
1 |
1 |
1 |
1 |
1 |
Test 10b (H.264): Turntable speed 2
Subjective Impairments H.323 |
384 kbit/s |
768 kbit/s |
2 Mbit/s |
4 Mbit/s |
6 Mbit/s |
BLK |
2 |
1 |
1 |
1 |
1 |
BLR |
2 |
1 |
1 |
1 |
1 |
CLR |
1 |
1 |
1 |
1 |
1 |
JRK |
1 |
1 |
1 |
1 |
1 |
Test 10c (H.264): Turntable speed 3
Subjective Impairments H.323 |
384 kbit/s |
768 kbit/s |
2 Mbit/s |
4 Mbit/s |
6 Mbit/s |
BLK |
2 |
1 |
1 |
1 |
1 |
BLR |
3 |
2 |
2 |
1 |
1 |
CLR |
1 |
1 |
1 |
1 |
1 |
JRK |
1 |
1 |
1 |
1 |
1 |
Test 10d (H.264): Turntable speed 4
Subjective Impairments H.323 |
384 kbit/s |
768 kbit/s |
2 Mbit/s |
4 Mbit/s |
6 Mbit/s |
BLK |
2 |
2 |
1 |
1 |
1 |
BLR |
3 |
3 |
2 |
2 |
2 |
CLR |
1 |
1 |
1 |
1 |
1 |
JRK |
1 |
1 |
1 |
1 |
1 |
Test 11 (H.264): Football sequence
Subjective Impairments H.323 |
384 kbit/s |
768 kbit/s |
2 Mbit/s |
4 Mbit/s |
6 Mbit/s |
BLK |
3 |
2 |
1 |
1 |
1 |
BLR |
4 |
3 |
2 |
2 |
1 |
CLR |
2 |
2 |
2 |
2 |
2 |
JRK |
1 |
1 |
1 |
1 |
1 |
Test 12 (H.264): Zoom in and zoom out of ‘A to Z’ map
Subjective Impairments H.323 |
384 kbit/s |
768 kbit/s |
2 Mbit/s |
4 Mbit/s |
6 Mbit/s |
BLK |
4 |
3 |
2 |
2 |
1 |
BLR |
4 |
3 |
2 |
1 |
1 |
CLR |
1 |
1 |
1 |
1 |
1 |
JRK |
2 |
2 |
1 |
1 |
1 |
Test 13 (H.264): Text legibility (% of screen height) at viewing distance approx.
5x screen diagonal
Legibility H.323 |
384 kbit/s |
768 kbit/s |
2 Mbit/s |
4 Mbit/s |
6 Mbit/s |
20 pt (3.5%) |
Yes |
Yes |
Yes |
Yes |
Yes |
16 pt (3%) |
Yes |
Yes |
Yes |
Yes |
Yes |
14 pt (2.5%) |
Yes |
Yes |
Yes |
Yes |
Yes |
12 pt (2.3%) |
No |
No |
Yes |
Yes |
Yes |
Test 14 (H.264): Video with several vision cuts
Subjective Impairments H.323 |
384 kbit/s |
768 kbit/s |
2 Mbit/s |
4 Mbit/s |
6 Mbit/s |
BLK |
3 |
2 |
1 |
1 |
1 |
BLR |
3 |
2 |
2 |
1 |
1 |
CLR |
1 |
1 |
1 |
1 |
1 |
OP |
1 |
1 |
1 |
1 |
1 |
SCR |
3 |
2 |
2 |
2 |
2 |
JRK |
2 |
2 |
1 |
1 |
1 |
Test 15 (H.264): Man teaching with flip chart
Subjective Impairments H.323 |
384 kbit/s |
768 kbit/s |
2 Mbit/s |
4 Mbit/s |
6 Mbit/s |
LS |
1 |
1 |
2 |
2 |
1 |
BLK |
2 |
1 |
1 |
1 |
1 |
BLR |
2 |
2 |
1 |
1 |
1 |
CLR |
1 |
1 |
1 |
1 |
1 |
JRK |
1 |
1 |
1 |
1 |
1 |
Test 16 Playback from a domestic VHS videotape player
As there is no analogue video input this test could not be carried out.