portapack-mayhem/firmware/baseband/block_decimator.hpp
Kyle Reed de81156223
Support for 1.25MHz capture (#1418)
* Advanced draft decim /4 just waterfall ok

* apply some Kall's corrections + formatting

* Tidy up both decim_factors

* New refine optimizations

* Format issues

* more format issues ...mmmm

* comments update

* WIP Cleanup

* WIP

* WIP - add variant

* Use std::visit to dispatch MultiDecimator -- fluent API

* Clean up comments

* Merge next and fix compilation

* Fix odd loop in BlockDecimator

* Clean up spectrum math

* Descibe spectrum update math better, more clear math.

* Apply spectrum interval correction at 1.5M

* Increase replay buffer to handle x4 ovs

---------

Co-authored-by: Brumi-2021 <ea3hqj@gmail.com>
2023-08-29 19:26:38 +02:00

93 lines
2.5 KiB
C++

/*
* Copyright (C) 2015 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.
*/
#ifndef __BLOCK_DECIMATOR_H__
#define __BLOCK_DECIMATOR_H__
#include <cstdint>
#include <cstddef>
#include <array>
#include "dsp_types.hpp"
#include "complex.hpp"
template <typename T, size_t N>
class BlockDecimator {
public:
constexpr BlockDecimator(
const size_t factor)
: factor_{factor} {
}
void set_input_sampling_rate(const uint32_t new_sampling_rate) {
if (new_sampling_rate != input_sampling_rate()) {
input_sampling_rate_ = new_sampling_rate;
reset_state();
}
}
uint32_t input_sampling_rate() const {
return input_sampling_rate_;
}
void set_factor(const size_t new_factor) {
if (new_factor != factor()) {
factor_ = new_factor;
reset_state();
}
}
size_t factor() const {
return factor_;
}
uint32_t output_sampling_rate() const {
return input_sampling_rate() / factor();
}
template <typename BlockCallback>
void feed(const buffer_t<T>& src, BlockCallback callback) {
/* NOTE: Input block size must be >= factor */
set_input_sampling_rate(src.sampling_rate);
for (size_t src_i = 0; src_i < src.count; src_i += factor()) {
buffer[dst_i++] = src.p[src_i];
if (dst_i == buffer.size()) {
callback({buffer.data(), buffer.size(), output_sampling_rate()});
reset_state();
}
}
}
private:
std::array<T, N> buffer{};
uint32_t input_sampling_rate_{0};
size_t factor_{1};
size_t dst_i{0};
void reset_state() {
dst_i = 0;
}
};
#endif /*__BLOCK_DECIMATOR_H__*/