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/*! \file audio.hcc
*
* \section generic Audio init and main loop
*
* \section project Project information.
* Project Graphic Equalizer\n
* \author
* \date 20041011
* \version 0.1
*
* \section copyright Copyright
* Copyright ©2004 Koninklijke Philips Electronics N.V. All rights reserved
*
* \section history Change history
* 20041011: \n Initial version
*
********************************************************************/
/******** System Includes *************/
#include <stdlib.hch>
#include "pal_master.hch"
/******** Application Includes ********/
#include "audio.hch"
/*! \fn void audio_init(gain_level, input_source,
* sample_rate, AUDIOIN, AUDIOOUT)
*
* \brief Set some inital values to the audio hardware.
*
* \param gain_level Set the input amplifier to this
* amplification level.
* \param input_source Choose between microphone input
* or linein input
* \param sample_rate Set the sample rate between 8000
* and 48000
*
* \return void
* \retval void
*
*/
macro proc audio_init(gain_level, input_source, sample_rate, AUDIOIN, AUDIOOUT) {
/*
* We simply call the appropiate handlers and pass values along. We
* Don't set the mute on input gain. We have volume control to do this.
* Input and Output sampling rates are equal. We dont' need different
* rates.
*/
RC200AudioInSetGain(FALSE, gain_level, gain_level);
RC200AudioInSetInput(input_source);
PalAudioInSetSampleRate(AUDIOIN, sample_rate);
PalAudioOutSetSampleRate(AUDIOOUT, sample_rate);
} /* --- audio_init() --- */
/*! \fn void audio_main(AUDIOIN, AUDIOOUT);
*
* \brief Main audiodriver. This function never returns! It calls the
* audiohandlers and stores samples into a global array. Once 64
* Samples are collected it raises a signal AUDIO_READY to let
* other processes know it's ready. We use quadruple buffering for
* audio input and double buffering for audio output.
*
* \param AUDIOIN Audio Input Handler
* \param AUDIOOUT Audio Output Handler
*
* \return Never Returns.
* \retval void
*/
macro proc audio_main(AUDIOIN, AUDIOOUT) {
/*
* Determin the data width for the current platform.
*/
macro expr IW = PalAudioInGetMaxDataWidthCT();
macro expr OW = PalAudioOutGetMaxDataWidthCT();
signed IW sample_left_in, sample_right_in;
signed OW sample_left_out, sample_right_out;
for (;;) {
PalAudioInRead(AUDIOIN, &sample_left_in, &sample_right_in);
/* par {
sample_add(sample_left_in);
sample_get(&sample_left_out);
sample_right_out = sample_right_in;
}
if (rotate_samples()) {
/ *
* 64 Samples have been processed, calculate.
* /
}
*/ PalAudioOutWrite(AUDIOOUT, (signed OW)(sample_left_in @ 0), (signed OW)(sample_right_in @ 0));
}
} /* --- audio_main() --- */
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