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authorStanislaw Halik <sthalik@misaki.pl>2015-10-30 07:37:41 +0100
committerStanislaw Halik <sthalik@misaki.pl>2015-10-30 08:39:32 +0100
commitaa066bdd4622d4f6824fee864f6be6806813f04d (patch)
tree3df328b8b364cba2373a85827191b259bd78d546 /filter-kalman/kalman.cpp
parentd6a54431d178632a2bf466c9904f74abd143afe6 (diff)
move to subdirectory-based build system
Closes #224
Diffstat (limited to 'filter-kalman/kalman.cpp')
-rw-r--r--filter-kalman/kalman.cpp129
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diff --git a/filter-kalman/kalman.cpp b/filter-kalman/kalman.cpp
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+/* Copyright (c) 2013 Stanisław Halik <sthalik@misaki.pl>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ */
+#include "ftnoir_filter_kalman.h"
+#include "opentrack/plugin-api.hpp"
+#include <QDebug>
+#include <cmath>
+
+constexpr double settings::mult_noise_stddev;
+
+FTNoIR_Filter::FTNoIR_Filter() {
+ reset();
+ prev_slider_pos = s.noise_stddev_slider;
+}
+
+// the following was written by Donovan Baarda <abo@minkirri.apana.org.au>
+// https://sourceforge.net/p/facetracknoir/discussion/1150909/thread/418615e1/?limit=25#af75/084b
+void FTNoIR_Filter::reset() {
+ // Setup kalman with state (x) is the 6 tracker outputs then
+ // their 6 corresponding velocities, and the measurement (z) is
+ // the 6 tracker outputs.
+ kalman.init(12, 6, 0, CV_64F);
+ // Initialize the transitionMatrix and processNoiseCov for
+ // dt=0.1. This needs to be updated each frame for the real dt
+ // value, but this hows you what they should look like. See
+ // http://en.wikipedia.org/wiki/Kalman_filter#Example_application.2C_technical
+ double dt = 0.1;
+ kalman.transitionMatrix = (cv::Mat_<double>(12, 12) <<
+ 1, 0, 0, 0, 0, 0, dt, 0, 0, 0, 0, 0,
+ 0, 1, 0, 0, 0, 0, 0, dt, 0, 0, 0, 0,
+ 0, 0, 1, 0, 0, 0, 0, 0, dt, 0, 0, 0,
+ 0, 0, 0, 1, 0, 0, 0, 0, 0, dt, 0, 0,
+ 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, dt, 0,
+ 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, dt,
+ 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1);
+ double accel_variance = accel_stddev * accel_stddev;
+ double a = dt * dt * accel_variance; // dt^2 * accel_variance.
+ double b = 0.5 * a * dt; // (dt^3)/2 * accel_variance.
+ double c = 0.5 * b * dt; // (dt^4)/4 * accel_variance.
+ kalman.processNoiseCov = (cv::Mat_<double>(12, 12) <<
+ c, 0, 0, 0, 0, 0, b, 0, 0, 0, 0, 0,
+ 0, c, 0, 0, 0, 0, 0, b, 0, 0, 0, 0,
+ 0, 0, c, 0, 0, 0, 0, 0, b, 0, 0, 0,
+ 0, 0, 0, c, 0, 0, 0, 0, 0, b, 0, 0,
+ 0, 0, 0, 0, c, 0, 0, 0, 0, 0, b, 0,
+ 0, 0, 0, 0, 0, c, 0, 0, 0, 0, 0, b,
+ b, 0, 0, 0, 0, 0, a, 0, 0, 0, 0, 0,
+ 0, b, 0, 0, 0, 0, 0, a, 0, 0, 0, 0,
+ 0, 0, b, 0, 0, 0, 0, 0, a, 0, 0, 0,
+ 0, 0, 0, b, 0, 0, 0, 0, 0, a, 0, 0,
+ 0, 0, 0, 0, b, 0, 0, 0, 0, 0, a, 0,
+ 0, 0, 0, 0, 0, b, 0, 0, 0, 0, 0, a);
+ cv::setIdentity(kalman.measurementMatrix);
+ const double noise_stddev = (1+s.noise_stddev_slider) * s.mult_noise_stddev;
+ const double noise_variance = noise_stddev * noise_stddev;
+ cv::setIdentity(kalman.measurementNoiseCov, cv::Scalar::all(noise_variance));
+ cv::setIdentity(kalman.errorCovPost, cv::Scalar::all(accel_variance * 1e4));
+ for (int i = 0; i < 6; i++) {
+ last_input[i] = 0;
+ }
+ timer.invalidate();
+}
+
+void FTNoIR_Filter::filter(const double* input, double *output)
+{
+ if (prev_slider_pos != s.noise_stddev_slider)
+ {
+ reset();
+ prev_slider_pos = s.noise_stddev_slider;
+ }
+ // Start the timer if it's not running.
+ if (!timer.isValid())
+ timer.start();
+ // Get the time in seconds since last run and restart the timer.
+ auto dt = timer.restart() / 1000.0f;
+ // Note this is a terrible way to detect when there is a new
+ // frame of tracker input, but it is the best we have.
+ bool new_input = false;
+ for (int i = 0; i < 6 && !new_input; i++)
+ new_input = (input[i] != last_input[i]);
+ // Update the transitionMatrix and processNoiseCov for dt.
+ double accel_variance = accel_stddev * accel_stddev;
+ double a = dt * dt * accel_variance; // dt^2 * accel_variance.
+ double b = 0.5 * a * dt; // (dt^3)/2 * accel_variance.
+ double c = 0.5 * b * dt; // (dt^4)/4 * accel_variance.
+ for (int i = 0; i < 6; i++) {
+ kalman.transitionMatrix.at<double>(i,i+6) = dt;
+ kalman.processNoiseCov.at<double>(i,i) = c;
+ kalman.processNoiseCov.at<double>(i+6,i+6) = a;
+ kalman.processNoiseCov.at<double>(i,i+6) = b;
+ kalman.processNoiseCov.at<double>(i+6,i) = b;
+ }
+ // Get the updated predicted position.
+ cv::Mat next_output = kalman.predict();
+ // If we have new tracker input, get the corrected position.
+ if (new_input) {
+ cv::Mat measurement(6, 1, CV_64F);
+ for (int i = 0; i < 6; i++) {
+ measurement.at<double>(i) = input[i];
+ // Save last_input for detecting new tracker input.
+ last_input[i] = input[i];
+ }
+ next_output = kalman.correct(measurement);
+ }
+ // Set output to the next_output.
+ for (int i = 0; i < 6; i++) {
+ output[i] = next_output.at<double>(i);
+ }
+}
+
+void FilterControls::doOK() {
+ s.b->save();
+ close();
+}
+
+void FilterControls::doCancel() {
+ s.b->reload();
+ close();
+}
+
+OPENTRACK_DECLARE_FILTER(FTNoIR_Filter, FilterControls, FTNoIR_FilterDll)