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/*
Copyright (C) 2009 Red Hat, Inc.
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
This library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include "playback.h"
#include "utils.h"
#include "debug.h"
#define REING_SIZE_MS 300
WavePlayer::WavePlayer(uint32_t samples_per_sec, uint32_t bits_per_sample, uint32_t channels, uint32_t frame_size)
: _pcm (NULL)
, _hw_params (NULL)
, _sw_params (NULL)
{
if (!init(samples_per_sec, bits_per_sample, channels, frame_size)) {
cleanup();
THROW("failed");
}
}
void WavePlayer::cleanup()
{
if (_pcm) {
snd_pcm_close(_pcm);
}
if (_hw_params) {
snd_pcm_hw_params_free(_hw_params);
}
if (_sw_params) {
snd_pcm_sw_params_free(_sw_params);
}
}
WavePlayer::~WavePlayer()
{
cleanup();
}
bool WavePlayer::init(uint32_t samples_per_sec,
uint32_t bits_per_sample,
uint32_t channels,
uint32_t frame_size)
{
const char* pcm_device = "default";
snd_pcm_format_t format;
int err;
switch (bits_per_sample) {
case 8:
format = SND_PCM_FORMAT_S8;
break;
case 16:
format = SND_PCM_FORMAT_S16_LE;
break;
default:
return false;
}
_samples_per_ms = samples_per_sec / 1000;
_frame_size = frame_size;
if ((err = snd_pcm_open(&_pcm, pcm_device, SND_PCM_STREAM_PLAYBACK, SND_PCM_NONBLOCK)) < 0) {
LOG_ERROR("cannot open audio playback device %s %s", pcm_device, snd_strerror(err));
return false;
}
if ((err = snd_pcm_hw_params_malloc(&_hw_params)) < 0) {
LOG_ERROR("cannot allocate hardware parameter structure %s", snd_strerror(err));
return false;
}
if ((err = snd_pcm_sw_params_malloc(&_sw_params)) < 0) {
LOG_ERROR("cannot allocate software parameter structure %s", snd_strerror(err));
return false;
}
if ((err = snd_pcm_hw_params_any(_pcm, _hw_params)) < 0) {
LOG_ERROR("cannot initialize hardware parameter structure %s", snd_strerror(err));
return false;
}
if ((err = snd_pcm_hw_params_set_rate_resample(_pcm, _hw_params, 1)) < 0) {
LOG_ERROR("cannot set rate resample %s", snd_strerror(err));
return false;
}
if ((err = snd_pcm_hw_params_set_access(_pcm, _hw_params,
SND_PCM_ACCESS_RW_INTERLEAVED)) < 0) {
LOG_ERROR("cannot set access type %s", snd_strerror(err));
return false;
}
if ((err = snd_pcm_hw_params_set_rate(_pcm, _hw_params, samples_per_sec, 0)) < 0) {
LOG_ERROR("cannot set sample rate %s", snd_strerror(err));
return false;
}
if ((err = snd_pcm_hw_params_set_channels(_pcm, _hw_params, channels)) < 0) {
LOG_ERROR("cannot set channel count %s", snd_strerror(err));
return false;
}
if ((err = snd_pcm_hw_params_set_format(_pcm, _hw_params, format)) < 0) {
LOG_ERROR("cannot set sample format %s", snd_strerror(err));
return false;
}
snd_pcm_uframes_t buffer_size;
buffer_size = (samples_per_sec * REING_SIZE_MS / 1000) / frame_size * frame_size;
if ((err = snd_pcm_hw_params_set_buffer_size_near(_pcm, _hw_params, &buffer_size)) < 0) {
LOG_ERROR("cannot set buffer size %s", snd_strerror(err));
return false;
}
int direction = 1;
snd_pcm_uframes_t period_size = (samples_per_sec * 20 / 1000) / frame_size * frame_size;
if ((err = snd_pcm_hw_params_set_period_size_near(_pcm, _hw_params, &period_size,
&direction)) < 0) {
LOG_ERROR("cannot set period size %s", snd_strerror(err));
return false;
}
if ((err = snd_pcm_hw_params(_pcm, _hw_params)) < 0) {
LOG_ERROR("cannot set parameters %s", snd_strerror(err));
return false;
}
if ((err = snd_pcm_sw_params_current(_pcm, _sw_params)) < 0) {
LOG_ERROR("cannot obtain sw parameters %s", snd_strerror(err));
return false;
}
err = snd_pcm_hw_params_get_buffer_size(_hw_params, &buffer_size);
if (err < 0) {
LOG_ERROR("unable to get buffer size for playback: %s", snd_strerror(err));
return false;
}
direction = 0;
err = snd_pcm_hw_params_get_period_size(_hw_params, &period_size, &direction);
if (err < 0) {
LOG_ERROR("unable to get period size for playback: %s", snd_strerror(err));
return false;
}
err = snd_pcm_sw_params_set_start_threshold(_pcm, _sw_params,
(buffer_size / period_size) * period_size);
if (err < 0) {
LOG_ERROR("unable to set start threshold mode for playback: %s", snd_strerror(err));
return false;
}
if ((err = snd_pcm_sw_params(_pcm, _sw_params)) < 0) {
LOG_ERROR("cannot set software parameters %s", snd_strerror(err));
return false;
}
if ((err = snd_pcm_prepare(_pcm)) < 0) {
LOG_ERROR("cannot prepare pcm device %s", snd_strerror(err));
return false;
}
return true;
}
bool WavePlayer::write(uint8_t* frame)
{
snd_pcm_sframes_t ret = snd_pcm_writei(_pcm, frame, _frame_size);
if (ret < 0) {
if (ret == -EAGAIN) {
return false;
}
DBG(0, "err %s", snd_strerror(-ret));
if (snd_pcm_recover(_pcm, ret, 1) == 0) {
snd_pcm_writei(_pcm, frame, _frame_size);
}
}
return true;
}
void WavePlayer::stop()
{
snd_pcm_drain(_pcm);
snd_pcm_prepare(_pcm);
}
bool WavePlayer::abort()
{
return true;
}
uint32_t WavePlayer::get_delay_ms()
{
ASSERT(_pcm);
snd_pcm_sframes_t delay;
if (snd_pcm_delay(_pcm, &delay) < 0) {
return 0;
}
return delay / _samples_per_ms;
}
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