Audio Element
Based on this Element you can implement internet audio streaming devices as shown in the Webradio Example.
It requires a ESP32 or ESP32-S3 processor that supports multiple tasks and PSRAM for buffering audio data.
The AudioElement uses the ESP32 specific audio library from https://github.com/schreibfaul1/ESP32-audioI2S that must be installed separately.
The AudioElement just adds a thin wrapper to configure and control the library. The Audio processing itself is started on another ESP32 FreeRTOS task and runs in the background.
There can only be one AudioElement created per device.
Element Configuration
The properties correspond to the api given by the audio library. However not all features are yet support by configuration.
url – set new streaming url
volume – set volume
balance – set right-left balance
low – adjust low-tone level in the range -20 … +6. Default level is 0.
mid – adjust mid-tone level in the range -20 … +6. Default level is 0.
high – adjust high-tone level in the range -20 … +6. Default level is 0.
mono – force mono mode as output. Default is 0 (stereo).
ontitle – these actions are send when a title is included in the streaming.
onstation – these actions are send when a station name is included in the streaming.
bclk* – set the pin used for the i2s clock signal
lrc* – set the pin used for the i2s LR signal
dout* – set the pin used for the i2s DOUT signal
* This parameter is mandatory and must be set. The element also supports RDS signals for the chips that decode these signals.
From the base element implementation the following properties are available for configuration:
title – Caption text for the element. Used by the element specific cards on the dash boards.
description – A line of text that gives a short description of the device used in the web UI.
room – The location of the device.
loglevel – This property holds the element specific log level. The default value is LOGGER_LEVEL_ERR == 1.
startup – This property can be used to start the element using a different initialization phase. Possible values are “sys”, “net”, “time”. See The Startup sequence.
Configuration Example
This example shows how to configure this element:
{
"audio": {
"0": {
"title": "audio processing",
"bclk": 26,
"lrc": 25,
"dout": 22,
"url": "audio/0?url=https://dispatcher.rndfnk.com/hr/hr3/live/mp3/high",
"ontitle": "displaytext/info?value=$v",
"onstation": "displaytext/station?value=$v"
}
}
}