X-Git-Url: http://git.osdn.net/view?p=android-x86%2Fhardware-intel-libsensors.git;a=blobdiff_plain;f=compass-calibration.c;h=602f4e2b2af1221f7dc4fee9dea1a59e18864e4c;hp=b4d2e49a5b7234da84f7fa15d7851ea29b8d5538;hb=refs%2Fheads%2Fnougat-x86;hpb=3af2df815c271329a4d29b8e082ff25917f406a4 diff --git a/compass-calibration.c b/compass-calibration.c index b4d2e49..602f4e2 100644 --- a/compass-calibration.c +++ b/compass-calibration.c @@ -1,68 +1,95 @@ /* - * Copyright (C) 2014 Intel Corporation. - */ +// Copyright (c) 2015 Intel Corporation +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. +*/ -#include -#include #include #include -#include -#include +#include #include #include "calibration.h" #include "matrix-ops.h" #include "description.h" -#ifdef DBG_RAW_DATA -#define MAX_RAW_DATA_COUNT 2000 -static FILE *raw_data = NULL; -static FILE *raw_data_selected = NULL; -static int raw_data_count = 0; -int file_no = 0; -#endif -/* We'll have multiple calibration levels -* so that we can provide an estimation as fast as possible -*/ -static const float min_diffs[CAL_STEPS] = { 0.2, 0.4, 0.6, 1.0 }; -static const float max_sqr_errs[CAL_STEPS] = { 10.0, 8.0, 5.0, 3.5 }; -static const unsigned int lookback_counts[CAL_STEPS] = { 3, 4, 5, 6 }; +/* Compass defines */ +#define COMPASS_CALIBRATION_PATH "/data/compass.conf" +#define EPSILON 0.000000001 + +#define MAGNETIC_LOW 960 /* 31 micro tesla squared */ +#define CAL_STEPS 5 +#define CAL_VERSION 1.0 + +/* We'll have multiple calibration levels so that we can provide an estimation as fast as possible */ +static const float min_diffs [CAL_STEPS] = {0.2, 0.25, 0.4, 0.6, 1.0}; +static const float max_sqr_errs [CAL_STEPS] = {10.0, 10.0, 8.0, 5.0, 3.5}; +static const unsigned int lookback_counts [CAL_STEPS] = {2, 3, 4, 5, 6 }; + -/* reset calibration algorithm */ -static void reset_sample (struct compass_cal* data) +/* Reset calibration algorithm */ +static void reset_sample (compass_cal_t* data) { int i,j; data->sample_count = 0; - for (i = 0; i < DS_SIZE; i++) + for (i = 0; i < MAGN_DS_SIZE; i++) for (j=0; j < 3; j++) data->sample[i][j] = 0; + + data->average[0] = data->average[1] = data->average[2] = 0; } -static double calc_square_err (struct compass_cal* data) + +static double calc_square_err (compass_cal_t* data) { double err = 0; double raw[3][1], result[3][1], mat_diff[3][1]; int i; + float stdev[3] = {0,0,0}; + double diff; - for (i = 0; i < DS_SIZE; i++) { + for (i = 0; i < MAGN_DS_SIZE; i++) { raw[0][0] = data->sample[i][0]; raw[1][0] = data->sample[i][1]; raw[2][0] = data->sample[i][2]; + stdev[0] += (raw[0][0] - data->average[0]) * (raw[0][0] - data->average[0]); + stdev[1] += (raw[1][0] - data->average[1]) * (raw[1][0] - data->average[1]); + stdev[2] += (raw[2][0] - data->average[2]) * (raw[2][0] - data->average[2]); + substract (3, 1, raw, data->offset, mat_diff); multiply(3, 3, 1, data->w_invert, mat_diff, result); - double diff = sqrt(result[0][0] * result[0][0] + result[1][0] * result[1][0] - + result[2][0] * result[2][0]) - data->bfield; + diff = sqrt(result[0][0] * result[0][0] + result[1][0] * result[1][0] + result[2][0] * result[2][0]) - data->bfield; err += diff * diff; } - err /= DS_SIZE; + + stdev[0] = sqrt(stdev[0] / MAGN_DS_SIZE); + stdev[1] = sqrt(stdev[1] / MAGN_DS_SIZE); + stdev[2] = sqrt(stdev[2] / MAGN_DS_SIZE); + + /* A sanity check - if we have too little variation for an axis it's best to reject the calibration than risking a wrong calibration */ + if (stdev[0] <= 1 || stdev[1] <= 1 || stdev[2] <= 1) + return max_sqr_errs[0]; + + err /= MAGN_DS_SIZE; return err; } -// Given an real symmetric 3x3 matrix A, compute the eigenvalues -static void compute_eigenvalues(double mat[3][3], double* eig1, double* eig2, double* eig3) + +/* Given an real symmetric 3x3 matrix A, compute the eigenvalues */ +static void compute_eigenvalues (double mat[3][3], double* eig1, double* eig2, double* eig3) { double p = mat[0][1] * mat[0][1] + mat[0][2] * mat[0][2] + mat[1][2] * mat[1][2]; @@ -96,16 +123,17 @@ static void compute_eigenvalues(double mat[3][3], double* eig1, double* eig2, do if (r <= -1.0) phi = M_PI/3; else if (r >= 1.0) - phi = 0; - else - phi = acos(r) / 3; + phi = 0; + else + phi = acos(r) / 3; *eig3 = q + 2 * p * cos(phi); *eig1 = q + 2 * p * cos(phi + 2 * M_PI / 3); *eig2 = 3 * q - *eig1 - *eig3; } -static void calc_evector(double mat[3][3], double eig, double vec[3][1]) + +static void calc_evector (double mat[3][3], double eig, double vec[3][1]) { double h[3][3]; double x_tmp[2][2]; @@ -131,14 +159,15 @@ static void calc_evector(double mat[3][3], double eig, double vec[3][1]) vec[2][0] = temp2 / norm; } + static int ellipsoid_fit (mat_input_t m, double offset[3][1], double w_invert[3][3], double* bfield) { int i; - double h[DS_SIZE][9]; - double w[DS_SIZE][1]; - double h_trans[9][DS_SIZE]; + double h[MAGN_DS_SIZE][9]; + double w[MAGN_DS_SIZE][1]; + double h_trans[9][MAGN_DS_SIZE]; double p_temp1[9][9]; - double p_temp2[9][DS_SIZE]; + double p_temp2[9][MAGN_DS_SIZE]; double temp1[3][3], temp[3][3]; double temp1_inv[3][3]; double temp2[3][1]; @@ -147,7 +176,7 @@ static int ellipsoid_fit (mat_input_t m, double offset[3][1], double w_invert[3] double a[3][3], sqrt_evals[3][3], evecs[3][3], evecs_trans[3][3]; double evec1[3][1], evec2[3][1], evec3[3][1]; - for (i = 0; i < DS_SIZE; i++) { + for (i = 0; i < MAGN_DS_SIZE; i++) { w[i][0] = m[i][0] * m[i][0]; h[i][0] = m[i][0]; h[i][1] = m[i][1]; @@ -159,11 +188,12 @@ static int ellipsoid_fit (mat_input_t m, double offset[3][1], double w_invert[3] h[i][7] = -1 * m[i][2] * m[i][2]; h[i][8] = 1; } - transpose (DS_SIZE, 9, h, h_trans); - multiply (9, DS_SIZE, 9, h_trans, h, result); + + transpose (MAGN_DS_SIZE, 9, h, h_trans); + multiply (9, MAGN_DS_SIZE, 9, h_trans, h, result); invert (9, result, p_temp1); - multiply (9, 9, DS_SIZE, p_temp1, h_trans, p_temp2); - multiply (9, DS_SIZE, 1, p_temp2, w, p); + multiply (9, 9, MAGN_DS_SIZE, p_temp1, h_trans, p_temp2); + multiply (9, MAGN_DS_SIZE, 1, p_temp2, w, p); temp1[0][0] = 2; temp1[0][1] = p[3][0]; @@ -185,7 +215,6 @@ static int ellipsoid_fit (mat_input_t m, double offset[3][1], double w_invert[3] double off_y = offset[1][0]; double off_z = offset[2][0]; - a[0][0] = 1.0 / (p[8][0] + off_x * off_x + p[6][0] * off_y * off_y + p[7][0] * off_z * off_z + p[3][0] * off_x * off_y + p[4][0] * off_x * off_z + p[5][0] * off_y * off_z); @@ -202,6 +231,9 @@ static int ellipsoid_fit (mat_input_t m, double offset[3][1], double w_invert[3] double eig1 = 0, eig2 = 0, eig3 = 0; compute_eigenvalues(a, &eig1, &eig2, &eig3); + if (eig1 <=0 || eig2 <= 0 || eig3 <= 0) + return 0; + sqrt_evals[0][0] = sqrt(eig1); sqrt_evals[1][0] = 0; sqrt_evals[2][0] = 0; @@ -230,54 +262,41 @@ static int ellipsoid_fit (mat_input_t m, double offset[3][1], double w_invert[3] transpose(3, 3, evecs, evecs_trans); multiply (3, 3, 3, temp1, evecs_trans, temp); transpose (3, 3, temp, w_invert); + *bfield = pow(sqrt(1/eig1) * sqrt(1/eig2) * sqrt(1/eig3), 1.0/3.0); + + if (*bfield < 0) + return 0; + multiply_scalar_inplace(3, 3, w_invert, *bfield); return 1; } -static void compass_cal_init (FILE* data_file, struct sensor_info_t* info) -{ - -#ifdef DBG_RAW_DATA - if (raw_data) { - fclose(raw_data); - raw_data = NULL; - } - if (raw_data_selected) { - fclose(raw_data_selected); - raw_data_selected = NULL; - } - - char path[64]; - snprintf(path, 64, RAW_DATA_FULL_PATH, file_no); - raw_data = fopen(path,"w+"); - snprintf(path, 64, RAW_DATA_SELECTED_PATH, file_no); - raw_data_selected = fopen(path,"w+"); - file_no++; - raw_data_count = 0; -#endif - - struct compass_cal* cal_data = (struct compass_cal*) info->cal_data; +static void compass_cal_init (FILE* data_file, sensor_info_t* info) +{ + compass_cal_t* cal_data = (compass_cal_t*) info->cal_data; + int cal_steps = (info->max_cal_level && info->max_cal_level <= CAL_STEPS) ? info->max_cal_level : CAL_STEPS; + float version; if (cal_data == NULL) return; - int data_count = 14; + int data_count = 15; reset_sample(cal_data); if (!info->cal_level && data_file != NULL) { - int ret = fscanf(data_file, "%d %lf %lf %lf %lf %lf %lf %lf %lf %lf %lf %lf %lf %lf", - &info->cal_level, &cal_data->offset[0][0], &cal_data->offset[1][0], &cal_data->offset[2][0], + int ret = fscanf(data_file, "%f %d %lf %lf %lf %lf %lf %lf %lf %lf %lf %lf %lf %lf %lf", + &version, &info->cal_level, + &cal_data->offset[0][0], &cal_data->offset[1][0], &cal_data->offset[2][0], &cal_data->w_invert[0][0], &cal_data->w_invert[0][1], &cal_data->w_invert[0][2], &cal_data->w_invert[1][0], &cal_data->w_invert[1][1], &cal_data->w_invert[1][2], &cal_data->w_invert[2][0], &cal_data->w_invert[2][1], &cal_data->w_invert[2][2], &cal_data->bfield); - if (ret != data_count) { + if (ret != data_count || info->cal_level >= cal_steps || version != CAL_VERSION) info->cal_level = 0; - } } if (info->cal_level) { @@ -286,7 +305,6 @@ static void compass_cal_init (FILE* data_file, struct sensor_info_t* info) cal_data->w_invert[0][0], cal_data->w_invert[0][1], cal_data->w_invert[0][2], cal_data->w_invert[1][0], cal_data->w_invert[1][1], cal_data->w_invert[1][2], cal_data->w_invert[2][0], cal_data->w_invert[2][1], cal_data->w_invert[2][2], cal_data->bfield); - } else { cal_data->offset[0][0] = 0; cal_data->offset[1][0] = 0; @@ -304,101 +322,102 @@ static void compass_cal_init (FILE* data_file, struct sensor_info_t* info) cal_data->bfield = 0; } - } -static void compass_store_result(FILE* data_file, struct sensor_info_t* info) + +static void compass_store_result (FILE* data_file, sensor_info_t* info) { - struct compass_cal* cal_data = (struct compass_cal*) info->cal_data; + compass_cal_t* cal_data = (compass_cal_t*) info->cal_data; if (data_file == NULL || cal_data == NULL) return; - int ret = fprintf(data_file, "%d %f %f %f %f %f %f %f %f %f %f %f %f %f\n", - info->cal_level, cal_data->offset[0][0], cal_data->offset[1][0], cal_data->offset[2][0], + int ret = fprintf(data_file, "%f %d %f %f %f %f %f %f %f %f %f %f %f %f %f\n", + CAL_VERSION, info->cal_level, + cal_data->offset[0][0], cal_data->offset[1][0], cal_data->offset[2][0], cal_data->w_invert[0][0], cal_data->w_invert[0][1], cal_data->w_invert[0][2], cal_data->w_invert[1][0], cal_data->w_invert[1][1], cal_data->w_invert[1][2], cal_data->w_invert[2][0], cal_data->w_invert[2][1], cal_data->w_invert[2][2], cal_data->bfield); if (ret < 0) - ALOGE ("compass calibration - store data failed!"); + ALOGE ("Compass calibration - store data failed!"); } -static int compass_collect (struct sensors_event_t* event, struct sensor_info_t* info, int64_t current_time) + +static int compass_collect (sensors_event_t* event, sensor_info_t* info) { float data[3] = {event->magnetic.x, event->magnetic.y, event->magnetic.z}; unsigned int index,j; unsigned int lookback_count; float min_diff; - struct compass_cal* cal_data = (struct compass_cal*) info->cal_data; + compass_cal_t* cal_data = (compass_cal_t*) info->cal_data; if (cal_data == NULL) return -1; /* Discard the point if not valid */ - if (data[0] == 0 && data[1] == 0 && data[2] == 0) + if (data[0] == 0 || data[1] == 0 || data[2] == 0) return -1; -#ifdef DBG_RAW_DATA - if (raw_data && raw_data_count < MAX_RAW_DATA_COUNT) { - fprintf(raw_data, "%f %f %f\n", (double)data[0], (double)data[1], - (double)data[2]); - raw_data_count++; - } - - if (raw_data && raw_data_count >= MAX_RAW_DATA_COUNT) { - fclose(raw_data); - raw_data = NULL; - } -#endif - lookback_count = lookback_counts[info->cal_level]; min_diff = min_diffs[info->cal_level]; - // For the current point to be accepted, each x/y/z value must be different enough - // to the last several collected points - if (cal_data->sample_count > 0 && cal_data->sample_count < DS_SIZE) { - unsigned int lookback = lookback_count < cal_data->sample_count ? lookback_count : - cal_data->sample_count; - for (index = 0; index < lookback; index++){ - for (j = 0; j < 3; j++) { + /* For the current point to be accepted, each x/y/z value must be different enough to the last several collected points */ + if (cal_data->sample_count > 0 && cal_data->sample_count < MAGN_DS_SIZE) { + unsigned int lookback = lookback_count < cal_data->sample_count ? lookback_count : cal_data->sample_count; + for (index = 0; index < lookback; index++) + for (j = 0; j < 3; j++) if (fabsf(data[j] - cal_data->sample[cal_data->sample_count-1-index][j]) < min_diff) { - ALOGV("CompassCalibration:point reject: [%f,%f,%f], selected_count=%d", - data[0], data[1], data[2], cal_data->sample_count); - return 0; + ALOGV("CompassCalibration:point reject: [%f,%f,%f], selected_count=%d", data[0], data[1], data[2], cal_data->sample_count); + return 0; } - } - } } - if (cal_data->sample_count < DS_SIZE) { + if (cal_data->sample_count < MAGN_DS_SIZE) { memcpy(cal_data->sample[cal_data->sample_count], data, sizeof(float) * 3); cal_data->sample_count++; - ALOGV("CompassCalibration:point collected [%f,%f,%f], selected_count=%d", - (double)data[0], (double)data[1], (double)data[2], cal_data->sample_count); -#ifdef DBG_RAW_DATA - if (raw_data_selected) { - fprintf(raw_data_selected, "%f %f %f\n", (double)data[0], (double)data[1], (double)data[2]); - } -#endif + cal_data->average[0] += data[0]; + cal_data->average[1] += data[1]; + cal_data->average[2] += data[2]; + ALOGV("CompassCalibration:point collected [%f,%f,%f], selected_count=%d", (double)data[0], (double)data[1], (double)data[2], cal_data->sample_count); } return 1; } -static void compass_compute_cal (struct sensors_event_t* event, struct sensor_info_t* info) + +static void scale_event (sensors_event_t* event) { - struct compass_cal* cal_data = (struct compass_cal*) info->cal_data; float sqr_norm = 0; float sanity_norm = 0; float scale = 1; - if (!info->cal_level || cal_data == NULL) - return; + sqr_norm = (event->magnetic.x * event->magnetic.x + + event->magnetic.y * event->magnetic.y + + event->magnetic.z * event->magnetic.z); + + if (sqr_norm < MAGNETIC_LOW) + sanity_norm = MAGNETIC_LOW; + + if (sanity_norm && sqr_norm) { + scale = sanity_norm / sqr_norm; + scale = sqrt(scale); + event->magnetic.x = event->magnetic.x * scale; + event->magnetic.y = event->magnetic.y * scale; + event->magnetic.z = event->magnetic.z * scale; + } +} + +static void compass_compute_cal (sensors_event_t* event, sensor_info_t* info) +{ + compass_cal_t* cal_data = (compass_cal_t*) info->cal_data; double result[3][1], raw[3][1], diff[3][1]; + if (!info->cal_level || cal_data == NULL) + return; + raw[0][0] = event->magnetic.x; raw[1][0] = event->magnetic.y; raw[2][0] = event->magnetic.z; @@ -406,62 +425,61 @@ static void compass_compute_cal (struct sensors_event_t* event, struct sensor_in substract(3, 1, raw, cal_data->offset, diff); multiply (3, 3, 1, cal_data->w_invert, diff, result); - sqr_norm = (result[0][0] * result[0][0] + - result[1][0] * result[1][0] + - result[2][0] * result[2][0]); - - sanity_norm = (sqr_norm < MAGNETIC_LOW) ? MAGNETIC_LOW : sanity_norm; - sanity_norm = (sqr_norm > MAGNETIC_HIGH) ? MAGNETIC_HIGH : sanity_norm; - - if (sanity_norm) { - scale = sanity_norm / sqr_norm; - scale = sqrt(scale); - result[0][0] = result[0][0] * scale; - result[1][0] = result[1][0] * scale; - result[2][0] = result[2][0] * scale; - } - event->magnetic.x = event->data[0] = result[0][0]; event->magnetic.y = event->data[1] = result[1][0]; event->magnetic.z = event->data[2] = result[2][0]; + + scale_event(event); } -static int compass_ready (struct sensor_info_t* info) +static int compass_ready (sensor_info_t* info) { mat_input_t mat; int i; float max_sqr_err; - struct compass_cal* cal_data = (struct compass_cal*) info->cal_data; + compass_cal_t* cal_data = (compass_cal_t*) info->cal_data; + compass_cal_t new_cal_data; - if (cal_data->sample_count < DS_SIZE) + /* + * Some sensors take unrealistically long to calibrate at higher levels. We'll use a max_cal_level if we have such a property setup, + * or go with the default settings if not. + */ + int cal_steps = (info->max_cal_level && info->max_cal_level <= CAL_STEPS) ? info->max_cal_level : CAL_STEPS; + + if (cal_data->sample_count < MAGN_DS_SIZE) return info->cal_level; max_sqr_err = max_sqr_errs[info->cal_level]; - /* enough points have been collected, do the ellipsoid calibration */ - for (i = 0; i < DS_SIZE; i++) { + /* Enough points have been collected, do the ellipsoid calibration */ + + /* Compute average per axis */ + cal_data->average[0] /= MAGN_DS_SIZE; + cal_data->average[1] /= MAGN_DS_SIZE; + cal_data->average[2] /= MAGN_DS_SIZE; + + for (i = 0; i < MAGN_DS_SIZE; i++) { mat[i][0] = cal_data->sample[i][0]; mat[i][1] = cal_data->sample[i][1]; mat[i][2] = cal_data->sample[i][2]; } - /* check if result is good */ - struct compass_cal new_cal_data; - /* the sample data must remain the same */ + /* Check if result is good. The sample data must remain the same */ new_cal_data = *cal_data; + if (ellipsoid_fit(mat, new_cal_data.offset, new_cal_data.w_invert, &new_cal_data.bfield)) { double new_err = calc_square_err (&new_cal_data); ALOGI("new err is %f, max sqr err id %f", new_err,max_sqr_err); if (new_err < max_sqr_err) { double err = calc_square_err(cal_data); if (new_err < err) { - /* new cal data is better, so we switch to the new */ + /* New cal data is better, so we switch to the new */ memcpy(cal_data->offset, new_cal_data.offset, sizeof(cal_data->offset)); memcpy(cal_data->w_invert, new_cal_data.w_invert, sizeof(cal_data->w_invert)); cal_data->bfield = new_cal_data.bfield; - if (info->cal_level < (CAL_STEPS - 1)) + if (info->cal_level < (cal_steps - 1)) info->cal_level++; ALOGV("CompassCalibration: ready check success, caldata: %f %f %f %f %f %f %f %f %f %f %f %f %f, err %f", cal_data->offset[0][0], cal_data->offset[1][0], cal_data->offset[2][0], cal_data->w_invert[0][0], @@ -475,54 +493,56 @@ static int compass_ready (struct sensor_info_t* info) return info->cal_level; } -void calibrate_compass (struct sensors_event_t* event, struct sensor_info_t* info, int64_t current_time) + +void calibrate_compass (int s, sensors_event_t* event) { - long current_time_ms = current_time / 1000000; int cal_level; /* Calibration is continuous */ - compass_collect (event, info, current_time_ms); + compass_collect (event, &sensor[s]); - cal_level = compass_ready(info); + cal_level = compass_ready(&sensor[s]); switch (cal_level) { - case 0: + scale_event(event); event->magnetic.status = SENSOR_STATUS_UNRELIABLE; break; case 1: - compass_compute_cal (event, info); + compass_compute_cal (event, &sensor[s]); event->magnetic.status = SENSOR_STATUS_ACCURACY_LOW; break; case 2: - compass_compute_cal (event, info); + compass_compute_cal (event, &sensor[s]); event->magnetic.status = SENSOR_STATUS_ACCURACY_MEDIUM; break; default: - compass_compute_cal (event, info); + compass_compute_cal (event, &sensor[s]); event->magnetic.status = SENSOR_STATUS_ACCURACY_HIGH; break; } } -void compass_read_data (struct sensor_info_t* info) +void compass_read_data (int s) { FILE* data_file = fopen (COMPASS_CALIBRATION_PATH, "r"); - compass_cal_init(data_file, info); + compass_cal_init(data_file, &sensor[s]); + if (data_file) fclose(data_file); } -void compass_store_data (struct sensor_info_t* info) + +void compass_store_data (int s) { FILE* data_file = fopen (COMPASS_CALIBRATION_PATH, "w"); - compass_store_result(data_file, info); + compass_store_result(data_file, &sensor[s]); + if (data_file) fclose(data_file); - }