Algorithms - PictureTel Concorde 4500 Servicing Manual

FREQUENTLY ASKED QUESTIONS

Algorithms

F-2
Q. Are there published figures on compression induced delay?
A.Yes.
See the following table for approximate values for a call being
made from one Concorde¥4500 to another Concorde¥4500.
Table F-1: Compression Induced Delay
Network Interface
a
H.320 (Link 64-E)
b
SG3
c
SG4
a. Assume CIF
b. Assume SG3 audio, not G.721
c. Assume G.728 or PT724 audio
Assume that for SG4 the audio algorithms are PT.724 or G.728
(low bit rate audio). If this is the case then there is no need to
break down delays by channel rate for rates of 128, 256, and 384
kbps. All delays are end-to-end.
Frames Per
Second
15 fps
30 fps
11 fps
15 fps
Compression
Induced Delay
350 milliseconds
310 milliseconds
450 milliseconds
310 milliseconds