liblinphone  3.5.2
Functions
Obtaining information about a running call: sound volumes, quality indicators

Functions

float linphone_call_get_play_volume (LinphoneCall *call)
float linphone_call_get_record_volume (LinphoneCall *call)
float linphone_call_get_current_quality (LinphoneCall *call)
float linphone_call_get_average_quality (LinphoneCall *call)

Detailed Description

When a call is running, it is possible to retrieve in real time current measured volumes and quality indicator.

Function Documentation

float linphone_call_get_play_volume ( LinphoneCall *  call)

Returns the measured sound volume played locally (received from remote) It is expressed in dbm0.

< Lowest measured that can be returned.

float linphone_call_get_record_volume ( LinphoneCall *  call)

Returns the measured sound volume recorded locally (sent to remote) It is expressed in dbm0.

< Lowest measured that can be returned.

float linphone_call_get_current_quality ( LinphoneCall *  call)

Obtain real-time quality rating of the call

Based on local RTP statistics and RTCP feedback, a quality rating is computed and updated during all the duration of the call. This function returns its value at the time of the function call. It is expected that the rating is updated at least every 5 seconds or so. The rating is a floating point number comprised between 0 and 5.

4-5 = good quality
3-4 = average quality
2-3 = poor quality
1-2 = very poor quality
0-1 = can't be worse, mostly unusable

Returns
The function returns -1 if no quality measurement is available, for example if no active audio stream exist. Otherwise it returns the quality rating.
float linphone_call_get_average_quality ( LinphoneCall *  call)

Returns call quality averaged over all the duration of the call.

See linphone_call_get_current_quality() for more details about quality measurement.