Pulse audio sine wave example

README.md

Sine wave player

This example demonstrates how to play a sine wave through Pulse audio. Keep in mind that this code does NOT do any error handling. This is about the minimal amount code needed to play a sine wave.

How to compile

sudo apt install libpulse-dev
gcc sine.c -o play -lm -lpulse-simple

sine.c

#define _USE_MATH_DEFINES

#include <pulse/simple.h>
#include <math.h>

#define SAMPLE_SIZE 40000

int main(){

    pa_simple *s;
    pa_sample_spec ss;
    
    ss.format = PA_SAMPLE_FLOAT32;
    ss.channels = 1;
    ss.rate = 44100;
    
    s = pa_simple_new(
        NULL,               // Use the default server.
        "sine player",       // Our application's name.
        PA_STREAM_PLAYBACK,
        NULL,               // Use the default device.
        "Music",            // Description of our stream.
        &ss,                // Our sample format.
        NULL,               // Use default channel map
        NULL,               // Use default buffering attributes.
        NULL                // Ignore error code.
    );

    float sin_datapoints[SAMPLE_SIZE];

    for(int i = 0; i < SAMPLE_SIZE; i++){
        float progress = M_PI * 2 * (i / 400.0);
        sin_datapoints[i] = sin(progress);
    }

    for(int i = 0; i < 10; i++) {
        pa_simple_write(s, sin_datapoints, sizeof(sin_datapoints), NULL);
    }

    pa_simple_drain(s, NULL);
    pa_simple_free(s);

    return 0;
}