mirror of
https://github.com/eried/portapack-mayhem.git
synced 2024-10-01 01:26:06 -04:00
73 lines
2.3 KiB
C++
73 lines
2.3 KiB
C++
/*
|
|
* Copyright (C) 2014 Jared Boone, ShareBrained Technology, Inc.
|
|
*
|
|
* This file is part of PortaPack.
|
|
*
|
|
* 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 2, 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; see the file COPYING. If not, write to
|
|
* the Free Software Foundation, Inc., 51 Franklin Street,
|
|
* Boston, MA 02110-1301, USA.
|
|
*/
|
|
|
|
#include "proc_wfm_audio.hpp"
|
|
|
|
#include <cstdint>
|
|
|
|
void WidebandFMAudio::execute(const buffer_c8_t& buffer) {
|
|
auto decimator_out = decimator.execute(buffer);
|
|
|
|
const buffer_s16_t work_audio_buffer {
|
|
(int16_t*)decimator_out.p,
|
|
sizeof(*decimator_out.p) * decimator_out.count
|
|
};
|
|
|
|
auto channel = decimator_out;
|
|
|
|
// TODO: Feed channel_stats post-decimation data?
|
|
feed_channel_stats(channel);
|
|
//feed_channel_spectrum(channel);
|
|
|
|
/* 768kHz complex<int16_t>[512]
|
|
* -> FM demodulation
|
|
* -> 768kHz int16_t[512] */
|
|
/* TODO: To improve adjacent channel rejection, implement complex channel filter:
|
|
* pass < +/- 100kHz, stop > +/- 200kHz
|
|
*/
|
|
|
|
auto audio_oversampled = demod.execute(decimator_out, work_audio_buffer);
|
|
|
|
/* 768kHz int16_t[512]
|
|
* -> 4th order CIC decimation by 2, gain of 1
|
|
* -> 384kHz int16_t[256] */
|
|
auto audio_8fs = audio_dec_1.execute(audio_oversampled, work_audio_buffer);
|
|
|
|
/* 384kHz int16_t[256]
|
|
* -> 4th order CIC decimation by 2, gain of 1
|
|
* -> 192kHz int16_t[128] */
|
|
auto audio_4fs = audio_dec_2.execute(audio_8fs, work_audio_buffer);
|
|
|
|
/* 192kHz int16_t[128]
|
|
* -> 4th order CIC decimation by 2, gain of 1
|
|
* -> 96kHz int16_t[64] */
|
|
auto audio_2fs = audio_dec_3.execute(audio_4fs, work_audio_buffer);
|
|
|
|
/* 96kHz int16_t[64]
|
|
* -> FIR filter, <15kHz (0.156fs) pass, >19kHz (0.198fs) stop, gain of 1
|
|
* -> 48kHz int16_t[32] */
|
|
auto audio = audio_filter.execute(audio_2fs, work_audio_buffer);
|
|
|
|
/* -> 48kHz int16_t[32] */
|
|
audio_hpf.execute_in_place(audio);
|
|
fill_audio_buffer(audio);
|
|
}
|