Haivision Makito, Руководство пользователя

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FAQ
Setting up Audio Talkback
Makito User’s Guide, v2.1.0, Issue 01 277
Setting up Audio Talkback
With the Talkback feature, the Makito encoder can be configured to listen for an uncom-
pressed PCM audio stream and output it via a mono analog audio connector.
However, the customer or system integrator must develop their own application to send the
audio stream to the encoder.
Upon request, Haivision provides a reference implementation (HaiPLAY v1.4.0) to aid
customer development.
Haivision’s Furnace v6.x InStream Media Player provides a Talkback audio stream to the
encoder. For more information, see the Furnace Administration Guide available through
Haivision’s Download Center.
Talkback Audio Format Specifications
Below is the exact specification required to send Talkback audio to Haivision encoders:
1.
Audio data in each payload is not compressed and is just PCM digitized audio. There
is no encoding/decoding involved.
2.
Transmitted over unicast UDP (right now only port # 9177) to the Makito.
3.
Audio sampling rate = 22.05 kHz (44.1 divided by 2).
4.
Each audio sample is a raw 16-bit PCM (LSB First).
5.
Mono audio only.
6.
Each UDP packet contains 440 samples.
7.
UDP payload is 880 bytes minium. (Anything beyond the 880th byte is discarded.)
8.
There is no audio mixing; one audio channel at a time: first in / first served. The talk-
back application software should be equipped with “push-to-talk” type of feature.
9.
If the audio input is disconnected, the application does not need to send filler zero
(silence) bytes, because talkback on the Makito inserts zeros (silence) to maintain the
output audio clock.
10.
Talkback audio is output over the “Audio Out” mono connector on the Makito
encoder.