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/*
* Copyright © 2011 Mozilla Foundation
*
* This program is made available under an ISC-style license. See the
* accompanying file LICENSE for details.
*/
/* libcubeb api/function test. Plays a simple tone. */
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <math.h>
#include "cubeb/cubeb.h"
#define SAMPLE_FREQUENCY 48000
#ifndef M_PI
#define M_PI 3.14159265358979323846
#endif
/* store the phase of the generated waveform */
struct cb_user_data {
long position;
};
long data_cb(cubeb_stream *stream, void *user, void *buffer, long nframes)
{
struct cb_user_data *u = (struct cb_user_data *)user;
short *b = (short *)buffer;
int i;
if (stream == NULL || u == NULL)
return CUBEB_ERROR;
/* generate our test tone on the fly */
for (i = 0; i < nframes; i++) {
/* North American dial tone */
b[i] = 16000*sin(2*M_PI*(i + u->position)*350/SAMPLE_FREQUENCY);
b[i] += 16000*sin(2*M_PI*(i + u->position)*440/SAMPLE_FREQUENCY);
/* European dial tone */
/*b[i] = 30000*sin(2*M_PI*(i + u->position)*425/SAMPLE_FREQUENCY);*/
}
/* remember our phase to avoid clicking on buffer transitions */
/* we'll still click if position overflows */
u->position += nframes;
return nframes;
}
void state_cb(cubeb_stream *stream, void *user, cubeb_state state)
{
struct cb_user_data *u = (struct cb_user_data *)user;
if (stream == NULL || u == NULL)
return;
switch (state) {
case CUBEB_STATE_STARTED:
printf("stream started\n"); break;
case CUBEB_STATE_STOPPED:
printf("stream stopped\n"); break;
case CUBEB_STATE_DRAINED:
printf("stream drained\n"); break;
default:
printf("unknown stream state %d\n", state);
}
return;
}
int main(int argc, char *argv[])
{
cubeb *ctx;
cubeb_stream *stream;
cubeb_stream_params params;
struct cb_user_data *user_data;
int ret;
ret = cubeb_init(&ctx, "Cubeb tone example");
if (ret != CUBEB_OK) {
fprintf(stderr, "Error initializing cubeb library\n");
return ret;
}
params.format = CUBEB_SAMPLE_S16NE;
params.rate = SAMPLE_FREQUENCY;
params.channels = 1;
user_data = malloc(sizeof(*user_data));
if (user_data == NULL) {
fprintf(stderr, "Error allocating user data\n");
return CUBEB_ERROR;
}
user_data->position = 0;
ret = cubeb_stream_init(ctx, &stream, "Cubeb tone (mono)", params,
250, data_cb, state_cb, user_data);
if (ret != CUBEB_OK) {
fprintf(stderr, "Error initializing cubeb stream\n");
return ret;
}
cubeb_stream_start(stream);
sleep(1);
cubeb_stream_stop(stream);
cubeb_stream_destroy(stream);
cubeb_destroy(ctx);
free(user_data);
return CUBEB_OK;
}
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