libsoundio/example/microphone.c
2015-07-23 15:04:41 -07:00

263 lines
8.7 KiB
C

/*
* Copyright (c) 2015 Andrew Kelley
*
* This file is part of libsoundio, which is MIT licensed.
* See http://opensource.org/licenses/MIT
*/
#include <soundio.h>
#include <stdio.h>
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
static enum SoundIoFormat prioritized_formats[] = {
SoundIoFormatFloat32NE,
SoundIoFormatFloat32FE,
SoundIoFormatS32NE,
SoundIoFormatS32FE,
SoundIoFormatS24NE,
SoundIoFormatS24FE,
SoundIoFormatS16NE,
SoundIoFormatS16FE,
SoundIoFormatFloat64NE,
SoundIoFormatFloat64FE,
SoundIoFormatU32NE,
SoundIoFormatU32FE,
SoundIoFormatU24NE,
SoundIoFormatU24FE,
SoundIoFormatU16NE,
SoundIoFormatU16FE,
SoundIoFormatS8,
SoundIoFormatU8,
SoundIoFormatInvalid,
};
__attribute__ ((cold))
__attribute__ ((noreturn))
__attribute__ ((format (printf, 1, 2)))
static void panic(const char *format, ...) {
va_list ap;
va_start(ap, format);
vfprintf(stderr, format, ap);
fprintf(stderr, "\n");
va_end(ap);
abort();
}
struct SoundIoRingBuffer *ring_buffer = NULL;
static void read_callback(struct SoundIoInStream *instream, int available_frame_count) {
int err;
struct SoundIoChannelArea *areas;
char *write_ptr = soundio_ring_buffer_write_ptr(ring_buffer);
int frames_left = available_frame_count;
for (;;) {
int frame_count = frames_left;
if ((err = soundio_instream_begin_read(instream, &areas, &frame_count)))
panic("begin read error: %s", soundio_strerror(err));
if (frame_count <= 0)
break;
if (!areas) {
// Due to an overflow there is a hole. Fill the ring buffer with
// silence for the size of the hole.
memset(write_ptr, 0, frame_count * instream->bytes_per_frame);
} else {
for (int frame = 0; frame < frame_count; frame += 1) {
for (int ch = 0; ch < instream->layout.channel_count; ch += 1) {
memcpy(write_ptr, areas[ch].ptr, instream->bytes_per_sample);
areas[ch].ptr += areas[ch].step;
write_ptr += instream->bytes_per_sample;
}
}
}
if ((err = soundio_instream_end_read(instream)))
panic("end read error: %s", soundio_strerror(err));
frames_left -= frame_count;
if (frames_left <= 0)
break;
}
int advance_frames = available_frame_count * instream->bytes_per_frame;
soundio_ring_buffer_advance_write_ptr(ring_buffer, advance_frames);
}
static void write_callback(struct SoundIoOutStream *outstream, int requested_frame_count) {
int err;
struct SoundIoChannelArea *areas;
char *read_ptr = soundio_ring_buffer_read_ptr(ring_buffer);
int fill_count = soundio_ring_buffer_fill_count(ring_buffer) / outstream->bytes_per_frame;
int frames_left = requested_frame_count;
int silence_count = frames_left - fill_count;
if (silence_count < 0)
silence_count = 0;
int total_read_count = requested_frame_count - silence_count;
for (;;) {
int frame_count = frames_left;
if ((err = soundio_outstream_begin_write(outstream, &areas, &frame_count)))
panic("begin write error: %s", soundio_strerror(err));
if (frame_count <= 0)
break;
int silence_frame_count = (silence_count < frame_count) ? silence_count : frame_count;
int read_count = frame_count - silence_frame_count;
for (int frame = 0; frame < silence_frame_count; frame += 1) {
for (int ch = 0; ch < outstream->layout.channel_count; ch += 1) {
memset(areas[ch].ptr, 0, outstream->bytes_per_sample);
areas[ch].ptr += areas[ch].step;
}
}
for (int frame = 0; frame < read_count; frame += 1) {
for (int ch = 0; ch < outstream->layout.channel_count; ch += 1) {
memcpy(areas[ch].ptr, read_ptr, outstream->bytes_per_sample);
areas[ch].ptr += areas[ch].step;
read_ptr += outstream->bytes_per_sample;
}
}
if ((err = soundio_outstream_end_write(outstream, frame_count)))
panic("end write error: %s", soundio_strerror(err));
frames_left -= frame_count;
if (frames_left <= 0)
break;
}
soundio_ring_buffer_advance_read_ptr(ring_buffer, total_read_count * outstream->bytes_per_frame);
}
static int usage(char *exe) {
fprintf(stderr, "Usage: %s [--dummy] [--alsa] [--pulseaudio]\n", exe);
return 1;
}
int main(int argc, char **argv) {
char *exe = argv[0];
enum SoundIoBackend backend = SoundIoBackendNone;
for (int i = 1; i < argc; i += 1) {
char *arg = argv[i];
if (strcmp("--dummy", arg) == 0) {
backend = SoundIoBackendDummy;
} else if (strcmp("--alsa", arg) == 0) {
backend = SoundIoBackendAlsa;
} else if (strcmp("--pulseaudio", arg) == 0) {
backend = SoundIoBackendPulseAudio;
} else {
return usage(exe);
}
}
struct SoundIo *soundio = soundio_create();
if (!soundio)
panic("out of memory");
int err = (backend == SoundIoBackendNone) ?
soundio_connect(soundio) : soundio_connect_backend(soundio, backend);
int default_out_device_index = soundio_get_default_output_device_index(soundio);
if (default_out_device_index < 0)
panic("no output device found");
int default_in_device_index = soundio_get_default_input_device_index(soundio);
if (default_in_device_index < 0)
panic("no output device found");
struct SoundIoDevice *out_device = soundio_get_output_device(soundio, default_out_device_index);
if (!out_device)
panic("could not get output device: out of memory");
struct SoundIoDevice *in_device = soundio_get_input_device(soundio, default_in_device_index);
if (!in_device)
panic("could not get input device: out of memory");
fprintf(stderr, "Input device: %s\n", in_device->description);
fprintf(stderr, "Output device: %s\n", out_device->description);
soundio_device_sort_channel_layouts(out_device);
const struct SoundIoChannelLayout *layout = soundio_best_matching_channel_layout(
out_device->layouts, out_device->layout_count,
in_device->layouts, in_device->layout_count);
if (!layout)
panic("channel layouts not compatible");
int sample_rate = 48000;
if (in_device->sample_rate_max < sample_rate) sample_rate = in_device->sample_rate_max;
if (out_device->sample_rate_max < sample_rate) sample_rate = out_device->sample_rate_max;
if (in_device->sample_rate_min > sample_rate || out_device->sample_rate_min > sample_rate)
panic("incompatible sample rates");
enum SoundIoFormat *fmt;
for (fmt = prioritized_formats; *fmt != SoundIoFormatInvalid; fmt += 1) {
if (soundio_device_supports_format(in_device, *fmt) &&
soundio_device_supports_format(out_device, *fmt))
{
break;
}
}
if (*fmt == SoundIoFormatInvalid)
panic("incompatible sample formats");
struct SoundIoInStream *instream = soundio_instream_create(in_device);
if (!instream)
panic("out of memory");
instream->format = *fmt;
instream->sample_rate = sample_rate;
instream->layout = *layout;
instream->period_duration = 0.1;
instream->read_callback = read_callback;
if ((err = soundio_instream_open(instream)))
panic("unable to open input stream: %s", soundio_strerror(err));
struct SoundIoOutStream *outstream = soundio_outstream_create(out_device);
if (!outstream)
panic("out of memory");
outstream->format = *fmt;
outstream->sample_rate = sample_rate;
outstream->layout = *layout;
outstream->buffer_duration = 0.2;
outstream->period_duration = 0.1;
outstream->write_callback = write_callback;
if ((err = soundio_outstream_open(outstream)))
panic("unable to open output stream: %s", soundio_strerror(err));
int capacity = 0.4 * instream->sample_rate * instream->bytes_per_frame;
ring_buffer = soundio_ring_buffer_create(soundio, capacity);
if (!ring_buffer)
panic("unable to create ring buffer: out of memory");
if ((err = soundio_instream_start(instream)))
panic("unable to start input device: %s", soundio_strerror(err));
if ((err = soundio_outstream_start(outstream)))
panic("unable to start output device: %s", soundio_strerror(err));
for (;;)
soundio_wait_events(soundio);
soundio_outstream_destroy(outstream);
soundio_instream_destroy(instream);
soundio_device_unref(in_device);
soundio_device_unref(out_device);
soundio_destroy(soundio);
return 0;
}