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Green screen when webcam comes up

Hi guys im very new to opencv and visual studio so ive just been running other peoples code to test and see what its all about anyway ive tested a few but all of them if the program starts and the camera feed comes up its green I can still see myself slightly if I move but ye its not right.

Any idea please? here is the code im trying at the moment:

//objectTrackingTutorial.cpp

//Written by Kyle Hounslow 2013

//Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software") //, to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, //and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

//The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

//THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, //FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER //LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS //IN THE SOFTWARE.

//*AREAS MARKED WITH ASTERISKS MODIFIED BY MARIA RAMOS //*DECEMBER 2014

define _CRT_SECURE_NO_DEPRECATE

include <sstream>

include <string>

include <iostream>

include <opencv\highgui.h>

include <opencv\cv.h>

include <chrono>

include <thread>

using namespace cv; //initial min and max HSV filter values. //these will be changed using trackbars int H_MIN = 0; int H_MAX = 256; int S_MIN = 0; int S_MAX = 256; int V_MIN = 0; int V_MAX = 256; //default capture width and height const int FRAME_WIDTH = 640; const int FRAME_HEIGHT = 480; //max number of objects to be detected in frame const int MAX_NUM_OBJECTS = 50; //minimum and maximum object area const int MIN_OBJECT_AREA = 20 * 20; const int MAX_OBJECT_AREA = FRAME_HEIGHTFRAME_WIDTH / 1.5; //names that will appear at the top of each window const string windowName = "Original Image"; const string windowName1 = "HSV Image"; const string windowName2 = "Thresholded Image"; const string windowName3 = "After Morphological Operations"; const string trackbarWindowName = "Trackbars"; void on_trackbar(int, void) {//This function gets called whenever a // trackbar position is changed

} string intToString(int number){

std::stringstream ss;
ss << number;
return ss.str();

} void createTrackbars(){ //create window for trackbars

namedWindow(trackbarWindowName, 0);
//create memory to store trackbar name on window
char TrackbarName[50];
sprintf(TrackbarName, "H_MIN", H_MIN);
sprintf(TrackbarName, "H_MAX", H_MAX);
sprintf(TrackbarName, "S_MIN", S_MIN);
sprintf(TrackbarName, "S_MAX", S_MAX);
sprintf(TrackbarName, "V_MIN", V_MIN);
sprintf(TrackbarName, "V_MAX", V_MAX);
//create trackbars and insert them into window
//3 parameters are: the address of the variable that is changing when the trackbar is moved(eg.H_LOW),
//the max value the trackbar can move (eg. H_HIGH), 
//and the function that is called whenever the trackbar is moved(eg. on_trackbar)
//                                  ---->    ---->     ---->      
createTrackbar("H_MIN", trackbarWindowName, &H_MIN, H_MAX, on_trackbar);
createTrackbar("H_MAX", trackbarWindowName, &H_MAX, H_MAX, on_trackbar);
createTrackbar("S_MIN", trackbarWindowName, &S_MIN, S_MAX, on_trackbar);
createTrackbar("S_MAX", trackbarWindowName, &S_MAX, S_MAX, on_trackbar);
createTrackbar("V_MIN", trackbarWindowName, &V_MIN, V_MAX, on_trackbar);
createTrackbar("V_MAX", trackbarWindowName, &V_MAX, V_MAX, on_trackbar);

} void drawObject(int x, int y, Mat &frame){

//use some of the openCV drawing functions to draw crosshairs
//on your tracked image!

//UPDATE:JUNE 18TH, 2013
//added 'if' and 'else' statements to prevent
//memory errors from writing off the screen (ie. (-25,-25) is not within the window!)

circle(frame, Point(x, y), 20, Scalar(0, 255, 0), 2);
if (y - 25>0)
    line(frame, Point(x, y), Point(x, y - 25), Scalar(0, 255, 0), 2);
else line(frame, Point(x, y), Point(x, 0), Scalar(0, 255, 0), 2);
if (y + 25<FRAME_HEIGHT)
    line(frame, Point(x, y), Point(x, y + 25), Scalar(0, 255, 0), 2);
else line(frame, Point(x, y), Point(x, FRAME_HEIGHT), Scalar(0, 255, 0), 2);
if (x - 25>0)
    line(frame, Point(x, y), Point(x - 25, y), Scalar(0, 255, 0), 2);
else line(frame, Point(x, y), Point(0, y), Scalar(0, 255, 0), 2);
if (x + 25<FRAME_WIDTH)
    line(frame, Point(x, y), Point(x + 25, y), Scalar(0, 255, 0), 2);
else line(frame, Point(x, y), Point(FRAME_WIDTH, y), Scalar(0, 255, 0), 2);

putText(frame, intToString(x) + "," + intToString(y), Point(x, y + 30), 1, 1, Scalar(0, 255, 0), 2);

} void morphOps(Mat &thresh){

//create structuring element that will be used to "dilate" and "erode" image.
//the element chosen here is a 3px by 3px rectangle

Mat erodeElement = getStructuringElement(MORPH_RECT, Size(3, 3));
//dilate with larger element so make sure object is nicely visible
Mat dilateElement = getStructuringElement(MORPH_RECT, Size(8, 8));

erode(thresh, thresh, erodeElement);
erode(thresh, thresh, erodeElement);


dilate(thresh, thresh, dilateElement);
dilate(thresh, thresh, dilateElement);

} void trackFilteredObject(int &x, int &y, Mat threshold, Mat &cameraFeed){

Mat temp;
threshold.copyTo(temp);
//these two vectors needed for output of findContours
vector< vector<Point> > contours;
vector<Vec4i> hierarchy;
//find contours of filtered image using openCV findContours function
findContours(temp, contours, hierarchy, CV_RETR_CCOMP, CV_CHAIN_APPROX_SIMPLE);
//use moments method to find our filtered object
double refArea = 0;
bool objectFound = false;
if (hierarchy.size() > 0) {
    int numObjects = hierarchy.size();
    //if number of objects greater than MAX_NUM_OBJECTS we have a noisy filter
    if (numObjects<MAX_NUM_OBJECTS){
        for (int index = 0; index >= 0; index = hierarchy[index][0]) {

            Moments moment = moments((cv::Mat)contours[index]);
            double area = moment.m00;

            //if the area is less than 20 px by 20px then it is probably just noise
            //if the area is the same as the 3/2 of the image size, probably just a bad filter
            //we only want the object with the largest area so we safe a reference area each
            //iteration and compare it to the area in the next iteration.
            if (area>MIN_OBJECT_AREA && area<MAX_OBJECT_AREA && area>refArea){
                x = moment.m10 / area;
                y = moment.m01 / area;
                objectFound = true;
                refArea = area;
            }
            else objectFound = false;


        }
        //let user know you found an object
        if (objectFound == true){
            putText(cameraFeed, "Tracking Object", Point(0, 50), 2, 1, Scalar(0, 255, 0), 2);
            //draw object location on screen
            drawObject(x, y, cameraFeed);
        }

    }
    else putText(cameraFeed, "TOO MUCH NOISE! ADJUST FILTER", Point(0, 50), 1, 2, Scalar(0, 0, 255), 2);
}

} int main(int argc, char* argv[]) { //some boolean variables for different functionality within this //program bool trackObjects = TRUE; bool useMorphOps = TRUE; //Matrix to store each frame of the webcam feed Mat cameraFeed; //matrix storage for HSV image Mat HSV; //matrix storage for binary threshold image Mat threshold; //x and y values for the location of the object int x = 0, y = 0; //create slider bars for HSV filtering createTrackbars(); //video capture object to acquire webcam feed VideoCapture capture; //open capture object at location zero (default location for webcam) capture.open(0); //* 0 =built-in, 1 = external //set height and width of capture frame capture.set(CV_CAP_PROP_FRAME_WIDTH, FRAME_WIDTH); capture.set(CV_CAP_PROP_FRAME_HEIGHT, FRAME_HEIGHT); //start an infinite loop where webcam feed is copied to cameraFeed matrix //all of our operations will be performed within this loop while (1){ //store image to matrix capture.read(cameraFeed); //convert frame from BGR to HSV colorspace cvtColor(cameraFeed, HSV, COLOR_BGR2HSV); //filter HSV image between values and store filtered image to //threshold matrix inRange(HSV, Scalar(H_MIN, S_MIN, V_MIN), Scalar(H_MAX, S_MAX, V_MAX), threshold); //perform morphological operations on thresholded image to eliminate noise //and emphasize the filtered object(s) if (useMorphOps) morphOps(threshold); //pass in thresholded frame to our object tracking function //this function will return the x and y coordinates of the //filtered object if (trackObjects) trackFilteredObject(x, y, threshold, cameraFeed);

    //show frames 
    imshow(windowName2, threshold);
    imshow(windowName, cameraFeed);
    imshow(windowName1, HSV);


    //delay 30ms so that screen can refresh.
    //image will not appear without this waitKey() command
    waitKey(30);

}






return 0;

}