hotword

A small example to detect a hotword from continous audio stream The decision was for ALSA to decrease overhaed. If this ends-up being to low-level, we'll investigate on portaudio. GStreamer was avoided due to GObject dependency.

MIC -> HW buffer -> readi -> app buffer 

Depends:

spdlog - C++ debugging library
alsa
libsndfile
porcupine: https://github.com/Picovoice/porcupine
libfvad: https://github.com/dpirch/libfvad

TODO:

spdlog compiles slowly
Unit test

References

https://www.alsa-project.org/alsa-doc/alsa-lib/index.html
http://alsamodular.sourceforge.net/alsa_programming_howto.html
https://gist.github.com/albanpeignier/104902
https://alsa.opensrc.org/HowTo_Asynchronous_Playback
https://gist.github.com/ghedo/963382/815c98d1ba0eda1b486eb9d80d9a91a81d995283

arecord -c2 -v -f S16_LE -D "hw:0" /tmp/test.wav
gst-launch-1.0 udpsrc port=12345 ! rawaudioparse use-sink-caps=false format=pcm pcm-format=s16le sample-rate=16000 num-channels=1 ! queue ! audioconvert ! audioresample ! filesink location=/tmp/udp.wav