Audio Control Characteristic
The Audio Control Characteristic value contains two fields; the first signals the audio codec to be used for the encoding and the second is for enablement / disablement of the audio recording. The Audio Control Characteristic value can be read using either the GATT Read Characteristic Value and is written using the GATT Write Characteristic Value or optional GATT Write Without Response sub-procedure. Only a single instance of this characteristic shall exist as part of the RDK Voice Service.
The characteristic UUID shall be set to: TBD
Audio Control Characteristic Value
The Audio Control Characteristic value shall be reset to the default value following connection establishment. Table below shows the data format of the characteristic value.
Name | Requirement | Format | Default Value |
---|---|---|---|
Audio Encoding | Mandatory | uint8 | 0x00 |
Audio Enable | Mandatory | uint8 | 0x00 |
Audio Control Encoding Value
The Audio Encoding setting of the Audio Control Characteristic shall only take effect the next time audio recording is started.
Changing the Audio Encoding value shall be ignored by the remote device if audio streaming is currently enabled, however reading this value shall always contain the last value written. Table below shows the possible values for the Audio Encoding value.
Value | Description |
---|---|
0 | Audio is to be encoded using the G.726 ADPCM codec |
1 | Audio is to be encoded using the IMA/DVI ADPCM codec |
2 | Audio is to encoded using the Opus codec. |
2 – 255 | Reserved for future use |
The RVS Client shall ensure that only codecs reported in the Audio Control Characteristic as available will be set in the Audio Control Encoding Value.
Audio Control Enable Value
The Audio Enable setting of the Audio Control Characteristic shall have only the values shown below.
Value | Description |
---|---|
0 | Disable audio streaming |
1 | Enable audio streaming |
2 – 255 | Reserved for future use |
Audio Control Enable Behaviour
When the Audio Enable Setting is toggled to 0x01 then audio data shall start to be sent via the Audio Data Characteristic provided notifications are enabled for the characteristic.