Polycom VSXTM 6000 User Manual

Page 11

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8

D:

VIDEO TESTS

Due to the automatic selection of video protocols we were unable to carry out the full
suite of tests.

In all tests at H.323 the corresponding audio standard is Siren™ 14, 48kbit/s

Objective Video Tests: Signal measurements
1. 75% EBU bars
2. 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


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



To ensure accuracy of measurement at the remote site, all signals are to be monitored
prior to transmission.

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