/* C example of using libpd with pulseaudio
* RECORD & PLAYBACK
*
* gcc -c main.c `pkg-config --cflags libpulse-simple` -o main.o "-I." "-I/home/psc/src/libpd/libpd_wrapper" "-I/home/psc/src/libpd/pure-data/src"
* gcc -o myapp main.o "-L." -O2 `pkg-config --libs libpulse-simple` /home/psc/src/libpd/libs/libpd.so
*
* http://www.workinprogress.ca/libpd
*/
#include <stdio.h>
// libpd
#include "z_libpd.h"
// pulseaudio
#include <pulse/simple.h>
#include <pulse/error.h>
#include <pulse/gccmacro.h>
#define NUMBERSECOND 10
#define SAMPLE_RATE 44100
#define NBCHANNEL 2
#define BLOCKSIZE 64
#define TICK 1
//libpd catch [print] function
void pdprint(const char *s) {
printf("%s", s);
}
int main(int argc, char **argv) {
if (argc < 3) {
fprintf(stderr, "usage: %s file folder\nexample: ./libpd echo.pd ./\n", argv[0]);
return -1;
}
// libpd
libpd_printhook = (t_libpd_printhook) pdprint;
libpd_init();
libpd_init_audio(NBCHANNEL, NBCHANNEL, SAMPLE_RATE, TICK); // input channel, output channel, sr, tick per buffer
// compute audio [; pd dsp 1(
libpd_start_message();
libpd_add_float(1.0f);
libpd_finish_message("pd", "dsp");
// open patch [; pd open file folder(
libpd_start_message();
libpd_add_symbol(argv[1]);
libpd_add_symbol(argv[2]);
libpd_finish_message("pd", "open");
// pulseaudio
// puredata use PA_SAMPLE_FLOAT32LE
static const pa_sample_spec ss = {
.format = PA_SAMPLE_FLOAT32LE,
.rate = SAMPLE_RATE,
.channels = NBCHANNEL,
};
// low-latency setting
pa_buffer_attr ba;
ba.tlength = pa_usec_to_bytes(50*1000, &ss);
ba.minreq = pa_usec_to_bytes(0, &ss);
ba.maxlength = pa_usec_to_bytes(50*1000, &ss);
ba.fragsize = sizeof(uint32_t) -1; //Adjust this value if it's glitchy
pa_simple *s = NULL;
pa_simple *r = NULL;
// init pulseaudio
int error;
if (!(r = pa_simple_new(NULL, "pdlib", PA_STREAM_RECORD, NULL, argv[1], &ss, NULL, &ba, &error))) {
fprintf(stderr, __FILE__": pa_simple_new() - record failed: %s\n", pa_strerror(error));
goto problem;
}
if (!(s = pa_simple_new(NULL, "pdlib", PA_STREAM_PLAYBACK, NULL, argv[1], &ss, NULL, &ba, &error))) {
fprintf(stderr, __FILE__": pa_simple_new() - playback failed: %s\n", pa_strerror(error));
goto problem;
}
// now run pd for ten seconds (logical time)
int i;
float inbuf[NBCHANNEL * BLOCKSIZE * TICK], outbuf[NBCHANNEL * BLOCKSIZE * TICK];
for (i = 0; i < NUMBERSECOND * SAMPLE_RATE / (BLOCKSIZE * TICK); i++) {
// pulseaudio input
if (pa_simple_read(r, inbuf, sizeof(t_float) * BLOCKSIZE * NBCHANNEL * TICK, &error) < 0) {
fprintf(stderr, __FILE__": pa_simple_read() failed: %s\n", pa_strerror(error));
goto problem;
}
// libpd process dsp
libpd_process_float(inbuf, outbuf);
// pulseaudio output
if (pa_simple_write(s, outbuf, sizeof(t_float) * BLOCKSIZE * NBCHANNEL * TICK, &error) < 0) {
fprintf(stderr, __FILE__": pa_simple_write() failed: %s\n", pa_strerror(error));
goto problem;
}
/*
//pulseaudio - report latency
pa_usec_t latency;
if ((latency = pa_simple_get_latency(s, &error)) == (pa_usec_t) -1) {
fprintf(stderr, __FILE__": pa_simple_get_latency() failed: %s\n", pa_strerror(error));
goto problem;
}
fprintf(stderr, "%0.0f usec \r", (float)latency);
*/
}
/* Make sure that every single sample was played */
if (pa_simple_drain(s, &error) < 0) {
fprintf(stderr, __FILE__": pa_simple_drain() failed: %s\n", pa_strerror(error));
goto problem;
}
pa_simple_free(s);
pa_simple_free(r);
return 0;
problem:
if (s) {
pa_simple_free(s);
}
if (r) {
pa_simple_free(r);
}
fprintf( stderr, "An error occured" );
return -1;
}
