Motion Detector

For this project, OpenGL and OpenCv libraries are used.

This application detects motion from video files and puts the motion in a frame highlight.

ofApp.H

Include the following header files:

• #include “ofMain.h"
• #include “ofxGui.h"
• #include “ofxOpenCv.h"
• #include “ofxCv.h" Declare the relevant parameters inside ofApp class

ofApp.cpp

void ofApp::setup()

This function is called once the program is executed. Load relevant files at this step.

• Example -> mySound.load("beep.wav"); (This line of code loads the “beep.wav” into mySound object, which is type ofSoundPlayer.)

ofFileDialogResult -> is used to open File Chooser Dialog ofxIntSlider -> is used to declare slider for gui ofVideoPlayer -> is used to declare an openFrameworks video

• Setup GUI elements Example -> gui.setup(); gui.add(playButton.setup(“Play”)); (This line of code generates the gui panel and adds a Button called “Play”)

void ofApp::update()

This function is called in every frame.

• use getPixels() to convert ofVideoPlayer object to ofPixels object.
• use toCv() to convert openFrameworks data to OpenCv data. In our code, toCv() is used to convert ofPixels data to OpenCv supported Matrix type.
• cvtColor() to apply an adaptive threshold to the Matrix.
• resize() the Matrix according to scaledWidth and scaledHeight
• use GaussianBlur on Matrix to reduce the image noise and reduce detail using a Point(25,25).

void ofApp::update()

Example on GaussianBlur

• create a copy of the current matrix.
• use absdiff( ) to compute the perelement absolute difference between both matrixes.
• Apply Treshold Binary.

• Use Dilation for 2 iteration on matrix generated by Threshold Binary method.
• Generate a copy of the Matrix to use for finding contours.

Example result from findContours

• Delete the previous Rect type vector by iterating between all members.
• Use an iteration for every contour and push back contours to a cv::Rect
• Call toOf() allocate a texture from Matrix
• Convert ofPixels data to ofTexture type.

void ofApp::draw() This function is used to draw images to the screen. • Video is drawn in this function every frame. • Draw Rectangles.

void ofApp::keyPressed(int key) This function handles key presses.

• Example:

if (key == ' ') { 
	playVideo(); 
	mySound.play(); 
} 

(The code above will play the video and play the sound file when space key is pressed.)