Create audio clip files for use with I²S Speakers

It is possible to create sound clips to include in your build to use with I²S speakers. No need for a media player component!

  • Using Audacity, convert audio to WAV, mono, 16kHz, Unsigned 8bit PCM

Audacity export dialog

  • Convert again, this time with SOX.

sox startup.wav --bits 8 --encoding signed-integer --endian little startup_again.raw

  • Now convert it into a hexadecimal string using xxd into a C++ file.

xxd -i startup_again.raw startup.c

  • The resulting file needs a modification in the start line: Open in an editor and change unsigned char startup_again_raw[] = {…[SNIP]…} to std::vector<unsigned char> startup_raw = {…[SNIP]…}.

Now you can rename the file to startup.h, put it inside the esphome configuration directory and put it in a include in your device config like this:

esphome:
  includes:
    - startup.h

Now you can define using the audio clip using the following:

- speaker.play:
    id: speaker
    data: !lambda return startup_raw;

Enjoy!

HowTo by [NUT].

See also