Skip to content

Play audio files (.wav) via the system bus of your computer and pickup with an AM radio

Notifications You must be signed in to change notification settings

anfractuosity/musicplayer

Folders and files

NameName
Last commit message
Last commit date

Latest commit

 

History

23 Commits
 
 
 
 
 
 

Repository files navigation

musicplayer

Play .wav audio file via system bus.

Based on the work of https://github.com/fulldecent/system-bus-radio

We make use of Pulse Density Modulation (PDM) (see https://en.wikipedia.org/wiki/Pulse-density_modulation for more information). The Pulse Code Modulation (PCM) data from a .wav file is converted to a PDM bit stream.

Each PDM bit, is output at the same sample rate as the audio. If we see a bit with a value of 1, we make use of the _mm_stream_si128 instructions, otherwise we simply use a busy-wait loop. We perform each of these operations for a duration of 1/samplerate seconds.

You simply use sox to convert your audio to a high sample rate such as 1MHz, as seen below (This high rate is necessary for PDM).

make
sox in.wav -r 1000000 out.wav
./musicplayer out.wav

Requirements

About

Play audio files (.wav) via the system bus of your computer and pickup with an AM radio

Topics

Resources

Stars

Watchers

Forks

Releases

No releases published

Packages

No packages published