A Node-RED node to give a provided sound (WAV,OGG) out on the defined output (hdmi or chinch or defined). This node is designed to work on Raspberry Pi and will be good in using with Watson APIs like text-to-speach to demonstrate cognitive iot.

Run the following command in the root directory of your Node-RED install or home directory (usually ~/.node-red).

    npm install node-red-node-speakerpi

sudo apt-get update sudo apt-get install libasound2-dev

amixer cset numid=3 1

amixer cset numid=3 2

alsamixer

##Usage

Provides a sound-node for sending out a sound to the connected speaker. There are two modes - filebased and streambased.

Within the filebased mode the Raspberry Pi Player APLAY is issued with a file. This brings out best quality with minimum resources needed from the play. If the msg.speech is given as an input it will be dumped into a file and after playing the temporary file it will be deleted. By defining msg.predefsound (set of predefined soundfiles within the package) or setting a msg.filename which includes /path/filename.wav - this will be played.

The streambased mode is for streaming directly the buffer into a speaker framework (using node-speaker)

The msg.speech as an input contains the WAV/OGG .

The node also needs a defined sound configuration which contains channels (1 or 2), the bitdepth (8 or 16) and the samplerate (22050 or 44100) set in the node or in the msg.speakerConfig for the sound in msg.speech.

speakerConfig = { 
	channels: 1
	bitdepth: 16
	samplerate: 22050
	 }