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| #include "opencv2/opencv.hpp"
#include "opencv2/highgui/highgui.hpp"
#include <iostream>
#include <stdlib.h>
#include <stdio.h>
// Maths methods
#define max(a, b) ((a) > (b) ? (a) : (b))
#define min(a, b) ((a) < (b) ? (a) : (b))
#define abs(x) ((x) > 0 ? (x) : -(x))
#define sign(x) ((x) > 0 ? 1 : -1)
// Step mooving for object min & max
#define STEP_MIN 5
#define STEP_MAX 100
IplImage *image;
// Position of the object we overlay
CvPoint objectPos = cvPoint(-1, -1);
// Color tracked and our tolerance towards it
int h = 0, s = 0, v = 0, tolerance = 10;
/*
* Transform the image into a two colored image, one color for the color we want to track, another color for the others colors
* From this image, we get two datas : the number of pixel detected, and the center of gravity of these pixel
*/
CvPoint binarisation(IplImage* image, int *nbPixels) {
int x, y;
CvScalar pixel;
IplImage *hsv, *mask;
IplConvKernel *kernel;
int sommeX = 0, sommeY = 0;
*nbPixels = 0;
// Create the mask &initialize it to white (no color detected)
mask = cvCreateImage(cvGetSize(image), image->depth, 1);
// Create the hsv image
hsv = cvCloneImage(image);
cvCvtColor(image, hsv, CV_BGR2HSV);
// We create the mask
cvInRangeS(hsv, cvScalar(h - tolerance -1, s - tolerance, 0), cvScalar(h + tolerance -1, s + tolerance, 255), mask);
// Create kernels for the morphological operation
kernel = cvCreateStructuringElementEx(5, 5, 2, 2, CV_SHAPE_ELLIPSE);
// Morphological opening (inverse because we have white pixels on black background)
cvDilate(mask, mask, kernel, 1);
cvErode(mask, mask, kernel, 1);
// We go through the mask to look for the tracked object and get its gravity center
for(x = 0; x < mask->width; x++) {
for(y = 0; y < mask->height; y++) {
// If its a tracked pixel, count it to the center of gravity's calcul
if(((uchar *)(mask->imageData + y*mask->widthStep))[x] == 255) {
sommeX += x;
sommeY += y;
(*nbPixels)++;
}
}
}
// Show the result of the mask image
cvShowImage("GeckoGeek Mask", mask);
// We release the memory of kernels
cvReleaseStructuringElement(&kernel);
// We release the memory of the mask
cvReleaseImage(&mask);
// We release the memory of the hsv image
cvReleaseImage(&hsv);
// If there is no pixel, we return a center outside the image, else we return the center of gravity
if(*nbPixels > 0)
return cvPoint((int)(sommeX / (*nbPixels)), (int)(sommeY / (*nbPixels)));
else
return cvPoint(-1, -1);
}
/*
* Add a circle on the video that fellow your colored object
*/
void addObjectToVideo(IplImage* image, CvPoint objectNextPos, int nbPixels) {
int objectNextStepX, objectNextStepY;
// Calculate circle next position (if there is enough pixels)
if (nbPixels > 10) {
// Reset position if no pixel were found
if (objectPos.x == -1 || objectPos.y == -1) {
objectPos.x = objectNextPos.x;
objectPos.y = objectNextPos.y;
}
// Move step by step the object position to the desired position
if (abs(objectPos.x - objectNextPos.x) > STEP_MIN) {
objectNextStepX = max(STEP_MIN, min(STEP_MAX, abs(objectPos.x - objectNextPos.x) / 2));
objectPos.x += (-1) * sign(objectPos.x - objectNextPos.x) * objectNextStepX;
}
if (abs(objectPos.y - objectNextPos.y) > STEP_MIN) {
objectNextStepY = max(STEP_MIN, min(STEP_MAX, abs(objectPos.y - objectNextPos.y) / 2));
objectPos.y += (-1) * sign(objectPos.y - objectNextPos.y) * objectNextStepY;
}
// -1 = object isn't within the camera range
} else {
objectPos.x = -1;
objectPos.y = -1;
}
// Draw an object (circle) centered on the calculated center of gravity
if (nbPixels > 10)
cvDrawCircle(image, objectPos, 15, CV_RGB(255, 0, 0), -1);
// We show the image on the window
cvShowImage("GeckoGeek Color Tracking", image);
}
/*
* Get the color of the pixel where the mouse has clicked
* We put this color as model color (the color we want to tracked)
*/
void getObjectColor(int event, int x, int y, int flags, void *param = NULL) {
// Vars
CvScalar pixel;
IplImage *hsv;
if(event == CV_EVENT_LBUTTONUP) {
// Get the hsv image
hsv = cvCloneImage(image);
cvCvtColor(image, hsv, CV_BGR2HSV);
// Get the selected pixel
pixel = cvGet2D(hsv, y, x);
// Change the value of the tracked color with the color of the selected pixel
h = (int)pixel.val[0];
s = (int)pixel.val[1];
v = (int)pixel.val[2];
// Release the memory of the hsv image
cvReleaseImage(&hsv);
}
}
int main() {
// Image & hsvImage
IplImage *hsv;
// Video Capture
CvCapture *capture;
// Key for keyboard event
char key;
// Number of tracked pixels
int nbPixels;
// Next position of the object we overlay
CvPoint objectNextPos;
// Initialize the video Capture (200 => CV_CAP_V4L2)
capture = cvCreateCameraCapture(200);
// Check if the capture is ok
if (!capture) {
printf("Can't initialize the video capture.\n");
return -1;
}
// Create the windows
cvNamedWindow("GeckoGeek Color Tracking", CV_WINDOW_AUTOSIZE);
cvNamedWindow("GeckoGeek Mask", CV_WINDOW_AUTOSIZE);
cvMoveWindow("GeckoGeek Color Tracking", 0, 100);
cvMoveWindow("GeckoGeek Mask", 650, 100);
// Mouse event to select the tracked color on the original image
cvSetMouseCallback("GeckoGeek Color Tracking", getObjectColor);
// While we don't want to quit
while(key != 'Q' && key != 'q') {
// We get the current image
image = cvQueryFrame(capture);
// If there is no image, we exit the loop
if(!image)
continue;
objectNextPos = binarisation(image, &nbPixels);
addObjectToVideo(image, objectNextPos, nbPixels);
// We wait 10 ms
key = cvWaitKey(10);
}
// Destroy the windows we have created
cvDestroyWindow("GeckoGeek Color Tracking");
cvDestroyWindow("GeckoGeek Mask");
// Destroy the capture
cvReleaseCapture(&capture);
return 0;
} |
