C++ ofxCvGrayscaleImage::absDiff方法代码示例

void update()
{
    // Update our little offset thingy.
    offset += 0.01;

    if (offset > 1) 
    {
        offset = 0;   
    }
    
    // Update our camera.
    grabber.update();
    
    // If the camera has a new frame to offer us ...
    if (grabber.isFrameNew())
    {
        // Make a copy of our grabber pixels in the colorImage.
        colorImage.setFromPixels(grabber.getPixelsRef());

        // When we assign a color image to a grayscale image, it is converted automatically.
        grayscaleImage = colorImage;
		
	    // If we set learnBackground to true using the keyboard, we'll take a snapshot of 
	    // the background and use it to create a clean foreground image.
		if (learnBackground == true)
		{
		    // We assign the grayscaleImage to the grayscaleBackgroundImage.
			grayscaleBackgroundImage = grayscaleImage;	
			
			// Now we set learnBakground so we won't set a background unless
			// explicitly directed to with a keyboard command.
			learnBackground = false;
		}

        // Create a difference image by comparing the background and the current grayscale images.
		grayscaleAbsoluteDifference.absDiff(grayscaleBackgroundImage, grayscaleImage);

        // Assign grayscaleAbsoluteDifference to the grayscaleBinary image.
        grayscaleBinary = grayscaleAbsoluteDifference;
        
        // Then threshold the grayscale image to create a binary image.
        grayscaleBinary.threshold(threshold, invert);

        // Find contours (blobs) that are between the size of 20 pixels and 
        // 1 / 3 * (width * height) of the camera. Also find holes.
		contourFinder.findContours(grayscaleBinary, 100, (width * height) / 3.0, 10, true);

        // Get the biggest blob and use it to draw.
        if (contourFinder.nBlobs > 0)
        {
            holePositions.addVertex(contourFinder.blobs[0].boundingRect.getCenter());
        }
        else 
        {
		   holePositions.clear(); 
        }
    }
}

void ofApp::update() {
    
    if (ofGetElapsedTimeMillis() - lastTime >= timeToReset) {
        lastTime = ofGetElapsedTimeMillis();
        bLearnBackground = true;
        bLearnBackground1 = true;
    }
    
    
    micLevelsTopNew[4] = contourFinder.nBlobs;
    micLevelsTopNew[5] = contourFinder1.nBlobs;
    
    
    /* NEW CAMERA CODE */
    
    bool bNewFrame = false;
    
    bool bNewFrame1 = false;
    
    vidGrabber.update();
    bNewFrame = vidGrabber.isFrameNew();
    
    vidGrabber1.update();
    bNewFrame1 = vidGrabber.isFrameNew();
    
    if (bNewFrame){
        
        colorImg.setFromPixels(vidGrabber.getPixels(), 320,240);
        
        grayImage = colorImg;
        if (bLearnBackground == true){
            grayBg = grayImage;		// the = sign copys the pixels from grayImage into grayBg (operator overloading)
            bLearnBackground = false;
        }
        grayDiff.absDiff(grayBg, grayImage);
        grayDiff.threshold(threshold);
        contourFinder.findContours(grayDiff, 20, (340*240)/3, 10, true);
    }
    
    if (bNewFrame1){
        
        colorImg1.setFromPixels(vidGrabber1.getPixels(), 320,240);
        
        grayImage1 = colorImg1;
        if (bLearnBackground1 == true){
            grayBg1 = grayImage1;
            bLearnBackground1 = false;
        }
        grayDiff1.absDiff(grayBg1, grayImage1);
        grayDiff1.threshold(threshold);
        contourFinder1.findContours(grayDiff1, 20, (340*240)/3, 10, true);
    }
    
    switch (ANIMATION_STATE) {
        case ACTIVATED: {
            int max_pos = 0;
            int max_element = -1000;
            for (int i = 0; i < 12; i++) {
                if (micLevelsTopNew[i] > max_element) {
                    max_pos = i;
                    max_element = micLevelsTopNew[i];
                }
            }
        
            for (int x = 0; x < 1280; x++) {
                float top = pow(x-bottomSwarm.b,2);
                float bottom = 2*pow(bottomSwarm.c,2);
                bottomSwarm.curve[x] = bottomSwarm.a*exp(-(top/bottom));
            }
            
            ofVec2f norm = swarmPosition;
            bottomSwarm.b = norm.normalize().x*1280-160;
//            ofVec2f btm = absColumnPositionTop[max_pos];
            ofVec2f btm = cameraPositionsTop[max_pos];
            ofVec2f desired =  btm - swarmPosition;
            float d = sqrt((desired.x*desired.x) + (desired.y+desired.y));
            desired.normalize();
            if (d < 100) {
                float m = ofMap(d, 0.0, 100.0, 0.0, 4.0);
                desired *= m;
            } else {
                desired *= 4.0;
            }

            swarmPosition += desired;
            
            /* UPDATE WAVES */
            for (int x = 0; x < 1280; x++) {
                gaussianBottom[x] = ofMap(bottomSwarm.curve[x], 0.0, 1.1, ambientLevel, 255.0);
            }
            break;
        }
        case DEACTIVATED: {
            
            for (int x = 0; x < 1280; x++) {
                float top = pow(x-bottomSwarm.b,2);
                float bottom = 2*pow(bottomSwarm.c,2);
                bottomSwarm.curve[x] = bottomSwarm.a*exp(-(top/bottom));
            }
            
//.........这里部分代码省略.........