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M17: FreqDevEstimator code cleanup

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f4exb 2022-07-27 23:16:22 +02:00
parent c2a91610c9
commit b5b6bdf825
2 changed files with 45 additions and 38 deletions
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1
modemm17/FreqDevEstimator.cpp
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@ -4,5 +4,6 @@ namespace modemm17 {
const std::array<float, 3> FreqDevEstimator::dc_b = { 0.09763107, 0.19526215, 0.09763107 }; const std::array<float, 3> FreqDevEstimator::dc_b = { 0.09763107, 0.19526215, 0.09763107 };
const std::array<float, 3> FreqDevEstimator::dc_a = { 1. , -0.94280904, 0.33333333 }; const std::array<float, 3> FreqDevEstimator::dc_a = { 1. , -0.94280904, 0.33333333 };
const float FreqDevEstimator::MAX_DC_ERROR = 0.2f;
} // namespace modemm17 } // namespace modemm17

82
modemm17/FreqDevEstimator.h
View File

@ -28,40 +28,19 @@ namespace modemm17 {
*/ */
class MODEMM17_API FreqDevEstimator class MODEMM17_API FreqDevEstimator
{ {
using sample_filter_t = BaseIirFilter<3>;
// IIR with Nyquist of 1/4.
static const std::array<float, 3> dc_b;
static const std::array<float, 3> dc_a;
static constexpr float MAX_DC_ERROR = 0.2;
float min_est_ = 0.0;
float max_est_ = 0.0;
float min_cutoff_ = 0.0;
float max_cutoff_ = 0.0;
float min_var_ = 0.0;
float max_var_ = 0.0;
size_t min_count_ = 0;
size_t max_count_ = 0;
float deviation_ = 0.0;
float offset_ = 0.0;
float error_ = 0.0;
float idev_ = 1.0;
sample_filter_t dc_filter_{dc_b, dc_a};
public: public:
using sample_filter_t = BaseIirFilter<3>;
void reset() void reset()
{ {
min_est_ = 0.0; min_est_ = 0.0f;
max_est_ = 0.0; max_est_ = 0.0f;
min_var_ = 0.0; min_var_ = 0.0f;
max_var_ = 0.0; max_var_ = 0.0f;
min_count_ = 0; min_count_ = 0;
max_count_ = 0; max_count_ = 0;
min_cutoff_ = 0.0; min_cutoff_ = 0.0f;
max_cutoff_ = 0.0; max_cutoff_ = 0.0f;
} }
void sample(float sample) void sample(float sample)
@ -70,8 +49,8 @@ public:
{ {
min_count_ = 1; min_count_ = 1;
min_est_ = sample; min_est_ = sample;
min_var_ = 0.0; min_var_ = 0.0f;
min_cutoff_ = min_est_ * 0.666666; min_cutoff_ = min_est_ * 0.666666f;
} }
else if (sample < min_cutoff_) else if (sample < min_cutoff_)
{ {
@ -80,12 +59,12 @@ public:
float var = (min_est_ / min_count_) - sample; float var = (min_est_ / min_count_) - sample;
min_var_ += var * var; min_var_ += var * var;
} }
else if (sample > 1.5 * max_est_) else if (sample > 1.5f * max_est_)
{ {
max_count_ = 1; max_count_ = 1;
max_est_ = sample; max_est_ = sample;
max_var_ = 0.0; max_var_ = 0.0f;
max_cutoff_ = max_est_ * 0.666666; max_cutoff_ = max_est_ * 0.666666f;
} }
else if (sample > max_cutoff_) else if (sample > max_cutoff_)
{ {
@ -104,27 +83,54 @@ public:
*/ */
void update() void update()
{ {
if (max_count_ < 2 || min_count_ < 2) return; if (max_count_ < 2 || min_count_ < 2) {
return;
}
float max_ = max_est_ / max_count_; float max_ = max_est_ / max_count_;
float min_ = min_est_ / min_count_; float min_ = min_est_ / min_count_;
deviation_ = (max_ - min_) / 6.0; deviation_ = (max_ - min_) / 6.0;
offset_ = dc_filter_(std::max(std::min(max_ + min_, deviation_ * MAX_DC_ERROR), deviation_ * -MAX_DC_ERROR)); offset_ = dc_filter_(std::max(std::min(max_ + min_, deviation_ * MAX_DC_ERROR), deviation_ * -MAX_DC_ERROR));
error_ = (std::sqrt(max_var_ / (max_count_ - 1)) + std::sqrt(min_var_ / (min_count_ - 1))) * 0.5; error_ = (std::sqrt(max_var_ / (max_count_ - 1)) + std::sqrt(min_var_ / (min_count_ - 1))) * 0.5;
if (deviation_ > 0) idev_ = 1.0 / deviation_;
min_cutoff_ = offset_ - deviation_ * 2; if (deviation_ > 0) {
idev_ = 1.0 / deviation_;
}
min_cutoff_ = offset_ - deviation_ * 2;
max_cutoff_ = offset_ + deviation_ * 2; max_cutoff_ = offset_ + deviation_ * 2;
max_est_ = max_; max_est_ = max_;
min_est_ = min_; min_est_ = min_;
max_count_ = 1; max_count_ = 1;
min_count_ = 1; min_count_ = 1;
max_var_ = 0.0; max_var_ = 0.0f;
min_var_ = 0.0; min_var_ = 0.0f;
} }
float deviation() const { return deviation_; } float deviation() const { return deviation_; }
float offset() const { return offset_; } float offset() const { return offset_; }
float error() const { return error_; } float error() const { return error_; }
float idev() const { return idev_; } float idev() const { return idev_; }
private:
// IIR with Nyquist of 1/4.
static const std::array<float, 3> dc_b;
static const std::array<float, 3> dc_a;
static const float MAX_DC_ERROR;
float min_est_ = 0.0f;
float max_est_ = 0.0f;
float min_cutoff_ = 0.0f;
float max_cutoff_ = 0.0f;
float min_var_ = 0.0f;
float max_var_ = 0.0f;
size_t min_count_ = 0;
size_t max_count_ = 0;
float deviation_ = 0.0f;
float offset_ = 0.0f;
float error_ = 0.0f;
float idev_ = 1.0f;
sample_filter_t dc_filter_{dc_b, dc_a};
}; };
} // modemm17 } // modemm17