gpu-screen-recorder/src/sound.cpp
2020-06-21 14:41:11 +02:00

155 lines
5.1 KiB
C++

/*
Copyright (C) 2020 dec05eba
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
#include "../include/sound.hpp"
#include <stdlib.h>
#include <stdio.h>
#ifdef PULSEAUDIO
#include <pulse/simple.h>
#include <pulse/error.h>
int sound_device_get_by_name(SoundDevice *device, const char *name, unsigned int num_channels, unsigned int period_frame_size) {
pa_sample_spec ss;
ss.format = PA_SAMPLE_S16LE;
ss.rate = 48000;
ss.channels = num_channels;
int error;
pa_simple *pa_handle = pa_simple_new(nullptr, "gpu-screen-recorder", PA_STREAM_RECORD, name, "record", &ss, nullptr, nullptr, &error);
if(!pa_handle) {
fprintf(stderr, "pa_simple_new() failed: %s\n", pa_strerror(error));
return -1;
}
int buffer_size = period_frame_size * 2 * num_channels; // 2 bytes/sample, @num_channels channels
void *buffer = malloc(buffer_size);
if(!buffer) {
fprintf(stderr, "failed to allocate buffer for audio\n");
pa_simple_free(pa_handle);
return -1;
}
fprintf(stderr, "Using pulseaudio\n");
device->handle = pa_handle;
device->buffer = buffer;
device->buffer_size = buffer_size;
device->frames = period_frame_size;
return 0;
}
void sound_device_close(SoundDevice *device) {
pa_simple_free((pa_simple*)device->handle);
free(device->buffer);
}
int sound_device_read_next_chunk(SoundDevice *device, void **buffer) {
int error;
if(pa_simple_read((pa_simple*)device->handle, device->buffer, device->buffer_size, &error) < 0) {
fprintf(stderr, "pa_simple_read() failed: %s\n", pa_strerror(error));
return -1;
}
*buffer = device->buffer;
return device->frames;
}
#else
#define ALSA_PCM_NEW_HW_PARAMS_API
#include <alsa/asoundlib.h>
int sound_device_get_by_name(SoundDevice *device, const char *name, unsigned int num_channels, unsigned int period_frame_size) {
int rc;
snd_pcm_t *handle;
rc = snd_pcm_open(&handle, name, SND_PCM_STREAM_CAPTURE, 0);
if(rc < 0) {
fprintf(stderr, "unable to open pcm device 'default', reason: %s\n", snd_strerror(rc));
return rc;
}
snd_pcm_hw_params_t *params;
snd_pcm_hw_params_alloca(&params);
// Fill the params with default values
snd_pcm_hw_params_any(handle, params);
// Interleaved mode
snd_pcm_hw_params_set_access(handle, params, SND_PCM_ACCESS_RW_INTERLEAVED);
// Signed 16--bit little-endian format
snd_pcm_hw_params_set_format(handle, params, SND_PCM_FORMAT_S16_LE);
snd_pcm_hw_params_set_channels(handle, params, num_channels);
// 48000 bits/second samling rate (DVD quality)
unsigned int val = 48000;
int dir;
snd_pcm_hw_params_set_rate_near(handle, params, &val, &dir);
snd_pcm_uframes_t frames = period_frame_size;
snd_pcm_hw_params_set_period_size_near(handle, params, &frames, &dir);
// Write the parmeters to the driver
rc = snd_pcm_hw_params(handle, params);
if(rc < 0) {
fprintf(stderr, "unable to set hw parameters, reason: %s\n", snd_strerror(rc));
snd_pcm_close(handle);
return rc;
}
// Use a buffer large enough to hold one period
snd_pcm_hw_params_get_period_size(params, &frames, &dir);
int buffer_size = frames * 2 * num_channels; // 2 bytes/sample, @num_channels channels
void *buffer = malloc(buffer_size);
if(!buffer) {
fprintf(stderr, "failed to allocate buffer for audio\n");
snd_pcm_close(handle);
return -1;
}
fprintf(stderr, "Using alsa\n");
device->handle = handle;
device->buffer = buffer;
device->buffer_size = buffer_size;
device->frames = frames;
return 0;
}
void sound_device_close(SoundDevice *device) {
/* TODO: Is this also needed in @sound_device_get_by_name on failure? */
// TODO: This has been commented out since it causes the thread to block forever. Why?
//snd_pcm_drain((snd_pcm_t*)device->handle);
snd_pcm_close((snd_pcm_t*)device->handle);
free(device->buffer);
}
int sound_device_read_next_chunk(SoundDevice *device, void **buffer) {
int rc = snd_pcm_readi((snd_pcm_t*)device->handle, device->buffer, device->frames);
if (rc == -EPIPE) {
/* overrun */
fprintf(stderr, "overrun occured\n");
snd_pcm_prepare((snd_pcm_t*)device->handle);
return rc;
} else if(rc < 0) {
fprintf(stderr, "failed to read from sound device, reason: %s\n", snd_strerror(rc));
return rc;
} else if (rc != (int)device->frames) {
fprintf(stderr, "short read, read %d frames\n", rc);
}
*buffer = device->buffer;
return rc;
}
#endif