Dialogic DIALOGIC MULTIMEDIA SOFTWARE FOR ADVANCEDTCA RELEASE 1.0 Parmchlatencyframeinitaudio

Models: 05-2548-006 DIALOGIC MULTIMEDIA SOFTWARE FOR ADVANCEDTCA RELEASE 1.0

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eIP_PARM Define

Description and Values

 

 

PARMCH_LATENCYFRAMEINIT_AUDIO

Specifies the amount of Packet Loss Recovery (PLR) latency

 

(delay) that can be introduced by defining the initial number of

 

frames that can be buffered. This parameter defines the

 

starting value for initial latency. When “fixed mode” is enabled

 

(see PARMCH_LATENCYALG_AUDIO), the number of frames

 

buffered can grow up to 1.5 times the starting value. For

 

example, if the parameter value is 6, the maximum number of

 

frames that can be buffered is 9. The PLR module attempts to

 

restore packets arriving at the receive end as close as possible

 

to their original time-stamped positions. Arriving packets are

 

decomposed into individual frames, each with a unique time

 

stamp. Each new frame is then stored in a jitter buffer before it

 

is sent to the decoder. This is done to allow packets arriving

 

out of order to be inserted in the queue in the correct order.

 

The size of this jitter buffer is defined by the number of frames

 

stored and is controlled by the

 

PARMCH_LATENCYFRAMEINIT_AUDIO,

 

PARMCH_LATENCYFRAMEMAX_AUDIO, and

 

PARMCH_LATENCYALG_AUDIO parameters.

 

Type: Integer. Values: 1 to

 

PARMCH_LATENCYFRAMEMAX_AUDIO (frames). Default: 6.

 

Note: While the number of frames to be buffered should be

 

set as high as possible for best quality, too high a value

 

will add unnecessary latency to the system. Generally,

 

the number of frames buffered should be the same size

 

or slightly larger than the number of frames per packet.

PARMCH_LATENCYFRAMEMAX_AUDIO

Defines the maximum number of frames to be buffered in the

 

Packet Loss Recovery (PLR) frame list. This parameter adds

 

latency only when the buffer is already filled and additional

 

frames arrive before there is space in the buffer. This provides

 

for bursts of packets to arrive, which would have to be

 

discarded otherwise. The PLR module attempts to restore

 

packets arriving at the receive end as close as possible to their

 

original time-stamped positions. Arriving packets are

 

decomposed into individual frames, each with a unique time

 

stamp. Each new frame is then stored in a jitter buffer before it

 

is sent to the decoder. This is done to allow packets arriving

 

out of order to be inserted in the queue in the correct order.

 

The size of this jitter buffer is defined by the number of frames

 

stored and is controlled by the

 

PARMCH_LATENCYFRAMEINIT_AUDIO,

 

PARMCH_LATENCYFRAMEMAX_AUDIO, and

 

PARMCH_LATENCYALG_AUDIO parameters.

 

Type: Integer. Values: 30 to 200 (frames). Default: 100.

 

Note: 1. On Windows® systems, the upper limit of the value is

 

dependent on the channel density and the kernel

 

memory availability.

 

2. While the number of frames to be buffered should be

 

set as high as possible for best quality, too high a value

 

will add unnecessary latency to the system. Generally,

 

the number of frames buffered should be the same size

 

or slightly larger than the number of frames per packet.

Dialogic® Multimedia Software for ATCA Release 1.0 Release Update, Rev 06 — January 23, 2008

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Dialogic Corporation

 

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Dialogic DIALOGIC MULTIMEDIA SOFTWARE FOR ADVANCEDTCA RELEASE 1.0 Parmchlatencyframeinitaudio, Parmchlatencyframemaxaudio