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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/***************************************************************************
* audioin.cc
*
* Wed Sep 30 11:36:18 CEST 2009
* Copyright 2011 Bent Bisballe Nyeng
* deva@aasimon.org
****************************************************************************/
/*
* This file is part of libaudioin.
*
* libaudioin 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 2 of the License, or
* (at your option) any later version.
*
* libaudioin 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 libaudioin; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
*/
#include "audioin.h"
AudioIn::AudioIn(std::string device, std::string mixer_interface,
unsigned int srate, int ch)
{
/*
frames = 940;
elem = NULL;
mixhnd = NULL;
int rc;
// Open PCM device for recording (capture).
rc = snd_pcm_open(&handle, device.c_str(), SND_PCM_STREAM_CAPTURE, 0);
if (rc < 0) throw CouldNotOpenPCMDevice();
// Allocate a hardware parameters object.
snd_pcm_hw_params_alloca(¶ms);
// Fill it in with default values.
rc = snd_pcm_hw_params_any(handle, params);
if (rc < 0) throw CouldNotInitialiseParams();
// Set the desired hardware parameters.
// Interleaved mode
rc = snd_pcm_hw_params_set_access(handle, params,
SND_PCM_ACCESS_RW_INTERLEAVED);
if (rc < 0) throw CouldNotSetAccessMode();
// Signed 16-bit little-endian format
rc = snd_pcm_hw_params_set_format(handle, params, SND_PCM_FORMAT_FLOAT);
if (rc < 0) throw CouldNotSetFormat();
// Set channels (stereo/mono)
rc = snd_pcm_hw_params_set_channels(handle, params, ch);
channels = ch;
if (rc < 0) throw CouldNotSetChannelNumber();
// Set sampling rate
unsigned int val = srate;
snd_pcm_hw_params_set_rate_near(handle, params, &val, &dir);
printf("srate: %d\n", val);
// if(val != srate) throw UnableToSetSampleRate();
// NOTE: Setting period size to 32 frames will force use of lowest possible value.
rc = snd_pcm_hw_params_set_period_size_near(handle, params, &frames, &dir);
if(rc < 0) throw UnableToSetPeriodSize();
// Write the parameters to the driver
rc = snd_pcm_hw_params(handle, params);
if (rc < 0) throw UnableToSetHWParams();
mixhnd = NULL;
*/
/*
//
// Set up mixer
//
snd_mixer_selem_id_t *mixer;
// Open mixer device
if(snd_mixer_open(&mixhnd, 0) != 0) throw MixerInitilisationFailed();
if(snd_mixer_attach(mixhnd, device.c_str()) != 0)
throw MixerInitilisationFailed();
if(snd_mixer_selem_register(mixhnd, NULL, NULL) < 0)
throw MixerInitilisationFailed();
if(snd_mixer_load(mixhnd) < 0)
throw MixerInitilisationFailed();
// Obtain mixer element
snd_mixer_selem_id_alloca(&mixer);
if(mixer == NULL) throw MixerInitilisationFailed();
snd_mixer_selem_id_set_name(mixer, mixer_interface.c_str());
elem = snd_mixer_find_selem(mixhnd, mixer);
if(elem == NULL) throw MixerInitilisationFailed();
if(snd_mixer_selem_get_capture_volume_range(elem, &lvl_min, &lvl_max) != 0)
throw MixerInitilisationFailed();
if(snd_mixer_selem_set_capture_switch(elem,
SND_MIXER_SCHN_FRONT_LEFT, 1) != 0)
throw MixerInitilisationFailed();
if(snd_mixer_selem_set_capture_switch(elem,
SND_MIXER_SCHN_FRONT_RIGHT, 1) != 0)
throw MixerInitilisationFailed();
// Obtain mixer enumeration element "Input Source" and set it to 2 (line).
snd_mixer_selem_id_set_name(mixer, "Input Source");
snd_mixer_elem_t *iselem = snd_mixer_find_selem(mixhnd, mixer);
if(iselem == NULL) return;
if(snd_mixer_selem_is_enumerated(iselem)) {
// Set to line-in
snd_mixer_selem_set_enum_item(iselem, SND_MIXER_SCHN_MONO, 2);
}
*/
}
AudioIn::~AudioIn()
{
if(handle) {
snd_pcm_drain(handle);
snd_pcm_close(handle);
}
if(mixhnd) snd_mixer_close(mixhnd);
}
#define TEST
#ifdef TEST
#include <math.h>
#endif/*TEST*/
size_t AudioIn::read(sample_t *buf, size_t size)
{
#ifdef TEST
static unsigned int x = 0;
for(size_t i = 0; i < size; i++) {
buf[i] = sin((float)x / 50.0);
x++;
}
return size;
#else
int rc;
if(size < frames * channels) {
throw PcmBufferTooSmall();
}
rc = snd_pcm_readi(handle, buf, frames);
if (rc == -EPIPE) {
// EPIPE means overrun
snd_pcm_prepare(handle);
throw OverRun();
return 0;
} else if (rc < 0) {
throw ReadError();
} else if (rc != (int)frames) {
throw ShortRead();
}
printf("rc: %d\n", rc);
return rc * channels;
#endif/*TEST*/
}
int AudioIn::set_level(unsigned int channel, float level)
{
if(!elem) throw MixerNotInitialised();
if(level > 1.0 || level < 0.0) throw InvalidMixerLevel();
long lvl = ((lvl_max - lvl_min) * level) + lvl_min;
snd_mixer_selem_channel_id_t ch;
switch(channel) {
case 0:
ch = SND_MIXER_SCHN_FRONT_LEFT;
break;
case 1:
ch = SND_MIXER_SCHN_FRONT_RIGHT;
break;
default:
throw IllegalChannelNumber();
break;
}
if(snd_mixer_selem_set_capture_volume(elem, ch, lvl) != 0) {
throw CouldNotSetMixerLevel();
}
return 0;
}
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