cosmopolitan/examples/a440.c
2024-09-11 03:49:29 -07:00

80 lines
2.6 KiB
C

#if 0
/*─────────────────────────────────────────────────────────────────╗
│ To the extent possible under law, Justine Tunney has waived │
│ all copyright and related or neighboring rights to this file, │
│ as it is written in the following disclaimers: │
│ • http://unlicense.org/ │
│ • http://creativecommons.org/publicdomain/zero/1.0/ │
╚─────────────────────────────────────────────────────────────────*/
#endif
#include <cosmoaudio.h>
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
/**
* @fileoverview plays pure A.440 tone on speakers for 1 second
* @see https://en.wikipedia.org/wiki/A440_%28pitch_standard%29
*/
#define SAMPLING_RATE 44100
#define WAVE_INTERVAL 440
#define CHANNELS 2
#define LOUDNESS .3
#define DEBUG_LOG 1
int main() {
struct CosmoAudioOpenOptions cao = {0};
cao.sizeofThis = sizeof(struct CosmoAudioOpenOptions);
cao.deviceType = kCosmoAudioDeviceTypePlayback;
cao.sampleRate = SAMPLING_RATE;
cao.debugLog = DEBUG_LOG;
cao.channels = CHANNELS;
int status;
struct CosmoAudio *ca;
status = cosmoaudio_open(&ca, &cao);
if (status != COSMOAUDIO_SUCCESS) {
fprintf(stderr, "failed to open audio: %d\n", status);
return 1;
}
float buf[256 * CHANNELS];
for (int g = 0; g < SAMPLING_RATE;) {
int frames = 1;
status = cosmoaudio_poll(ca, NULL, &frames);
if (status != COSMOAUDIO_SUCCESS) {
fprintf(stderr, "failed to poll output: %d\n", status);
return 2;
}
if (frames > 256)
frames = 256;
if (frames > SAMPLING_RATE - g)
frames = SAMPLING_RATE - g;
for (int f = 0; f < frames; ++f) {
float t = (float)g++ / SAMPLING_RATE;
float s = sinf(2 * M_PIf * WAVE_INTERVAL * t);
for (int c = 0; c < CHANNELS; c++)
buf[f * CHANNELS + c] = s * LOUDNESS;
}
status = cosmoaudio_write(ca, buf, frames);
if (status != frames) {
fprintf(stderr, "failed to write output: %d\n", status);
return 3;
}
}
status = cosmoaudio_flush(ca);
if (status != COSMOAUDIO_SUCCESS) {
fprintf(stderr, "failed to flush output: %d\n", status);
return 4;
}
status = cosmoaudio_close(ca);
if (status != COSMOAUDIO_SUCCESS) {
fprintf(stderr, "failed to close audio: %d\n", status);
return 5;
}
}