File content as of revision 7:d79cbeda2982:

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/*
 * $Date$
 * $Revision$
 */

#include "tof_gestures.h"
#include "tof_gestures_SWIPE_1.h"

int tof_gestures_initSWIPE_1(Gesture_SWIPE_1_Data_t *data){
    int status=0;
    status |= (int)(RB_init(&(data->rangeList),SWIPE_1_BUFFER_SIZE));
    data->meanBackground = 0;
    data->meanHand = 0;
    data->gestureCode = GESTURES_NULL;
    data->cpt = SWIPE_1_SENSITIVITY;
    return status;
}

int tof_gestures_detectSWIPE_1(int32_t range_mm, Gesture_SWIPE_1_Data_t *data){
    int time = GET_TIME_STAMP();

    /* Default state */
    if (data->gestureCode == GESTURES_NULL){
    	// Calculate background distance (averaging)
    	data->meanBackground = (data->rangeList.count==0) ? 0 : RB_mean(&(data->rangeList));
    	// Check current distance vs background distance
    	if (range_mm < (int)((1-SWIPE_1_BACKGROUND_VARIATION) * data->meanBackground)){
    		// big variation detected => hand entering in FoV
    		if (data->cpt == 0) {
    			// Potential spikes (duster ?) skipped
    			data->cpt = SWIPE_1_SENSITIVITY;
				data->gestureCode = GESTURES_HAND_ENTERING;
				RB_init(&(data->rangeList),SWIPE_1_BUFFER_SIZE);
				RB_push(&(data->rangeList), range_mm);
				data->timestamp = time;
				TOF_GESTURES_DEBUG(SWIPE_1,"(background=%d, current=%d) => HAND_ENTERING", data->meanBackground, range_mm);
    		} else {
    			data->cpt--;
    			TOF_GESTURES_DEBUG(SWIPE_1,"(background=%d, current=%d) => SKIP", data->meanBackground, range_mm);
    		}
    	}else{
    		// no variation => keep averaging background
    		RB_push(&(data->rangeList), range_mm);
    	}

    /* Hand entering */
    } else if (data->gestureCode == GESTURES_HAND_ENTERING){
    	// Calculate hand distance (averaging)
    	data->meanHand = (data->rangeList.count==0) ? 0 : RB_mean(&(data->rangeList));
    	// Check current distance vs hand mean distance
    	if ((range_mm < (data->meanHand * (1-SWIPE_1_HAND_VARIATION))) || (((data->meanHand * (1+SWIPE_1_HAND_VARIATION)) < range_mm))){
    		// Big variation => Hand leaving
			data->gestureCode = GESTURES_HAND_LEAVING;
			RB_init(&(data->rangeList),SWIPE_1_BUFFER_SIZE);
			RB_push(&(data->rangeList), range_mm);
			data->timestamp = time;
			TOF_GESTURES_DEBUG(SWIPE_1,"(meanHand=%d, current=%d) => HAND_LEAVING", data->meanHand, range_mm);
    	} else if ((time - data->timestamp) > SWIPE_1_MAX_SWIPE_DURATION) {
    		// Too slow => discard (swipe is too slow, this may be a background change for a long time)
			data->gestureCode = GESTURES_DISCARDED_TOO_SLOW;
			RB_init(&(data->rangeList),SWIPE_1_BUFFER_SIZE);
			TOF_GESTURES_DEBUG(SWIPE_1,"DISCARDED_TOO_SLOW");
    	} else {
    		// No big variation => remains in this state
			RB_push(&(data->rangeList), range_mm);
			TOF_GESTURES_DEBUG(SWIPE_1, "Wait (meanHand=%d, current=%d)", data->meanHand, range_mm);
    	}

    /* Hand leaving */
    } else if (data->gestureCode == GESTURES_HAND_LEAVING){
    	// Check current distance vs background distance (previously calculated)
    	if (((data->meanBackground * (1-SWIPE_1_BACKGROUND_VARIATION)) < range_mm) && (range_mm < ((data->meanBackground * (1+SWIPE_1_BACKGROUND_VARIATION))))){
    		// Almost same => Swipe detected/finished
    		data->gestureCode = GESTURES_SINGLE_SWIPE;
    		//data->cpt = 0;
    		RB_init(&(data->rangeList),SWIPE_1_BUFFER_SIZE);
    		//return_code = GESTURES_SINGLE_SWIPE;
    		TOF_GESTURES_DEBUG(SWIPE_1, "(background=%d, current==%d) => SINGLE_SWIPE\n", data->meanBackground, range_mm);
    		//uart_printf("2 : Next state : %d, (background=%d), range=%d (SWIPE)\n", data->gestureCode, data->meanBackground, range_mm);
    	} else if ((time - data->timestamp) > SWIPE_1_BACKGROUND_TIMEOUT){
    		// To slow to converge back to background distance => discard (background may have change during the gesture)
    		data->gestureCode = GESTURES_DISCARDED;
			RB_init(&(data->rangeList),SWIPE_1_BUFFER_SIZE);
			TOF_GESTURES_DEBUG(SWIPE_1,"DISCARDED");
    	} else {
    		// Wait for convergence towards background
    		TOF_GESTURES_DEBUG(SWIPE_1,"Wait (background=%d, current=%d)", data->meanBackground, range_mm);
    	}

    /* Swipe detected or discarded */
    } else {
    	data->gestureCode = GESTURES_NULL;
    }

    return data->gestureCode;
}