Motion Animation - Greg Parsons
Midterm Project
- Motivation
- I was interested in the demonstrations of computer vision presented during the first week of lecture. Using the in class sampling of the technologies I was impressed by how I was able to manipulate a project using frame differencing. I would like to create a project that is manipulated by movements from the viewer of the project.
- Interaction
- The interaction of the project will be enacted with a webcam, recording movement in a scene and manipulating a graphical image based on the data collected from the difference in frames. In total the project would react to the viewers movements in some way.
- Function
- My programming experience is limited to the past two quarters of instruction. But I would like to be able to achieve smooth movement in the image using some form of algorithmic processing.
- Visualization
- I have a semi-working project that I created this weekend using a visual example from OpenProcessing.org that I will show in class if needed.
Code for Demo:
Copy this into a new processing project to test.
/** * Greg Parsons VIS145B Midterm Test * * Project Uses Frame Differencing to detect motion, sees it and draws a picture * */ //videocapture import processing.video.*; float x, y; int numPixels; int[] previousFrame; int[] diffFrame; Capture video; //treecursion float curlx = 0; float curly = 0; float f = sqrt(2)/2.; float deley = 20; float growth = 0; float growthTarget = 0; int movementDiff = constrain(10, 5, 15); int movementDiffNegative = constrain(10, -5, -10); void setup() { //video capture size(640, 480, P2D); //P2D from treecursion video = new Capture(this, width, height, 24); numPixels = video.width * video.height; previousFrame = new int[numPixels]; diffFrame = new int[numPixels]; loadPixels(); smooth(); //treecursion addMouseWheelListener(new java.awt.event.MouseWheelListener() { public void mouseWheelMoved(java.awt.event.MouseWheelEvent evt) { mouseWheel(evt.getWheelRotation()); } } ); } void draw() { //video capture if (video.available()) { // When using video to manipulate the screen, use video.available() and // video.read() inside the draw() method so that it's safe to draw to the screen video.read(); // Read the new frame from the camera video.loadPixels(); // Make its pixels[] array available int movementSum = 0; // Amount of movement in the frame for (int i = 0; i < numPixels; i++) { // For each pixel in the video frame... color currColor = video.pixels[i]; color prevColor = previousFrame[i]; // Extract the red, green, and blue components from current pixel int currR = (currColor >> 16) & 0xFF; // Like red(), but faster int currG = (currColor >> 8) & 0xFF; int currB = currColor & 0xFF; // Extract red, green, and blue components from previous pixel int prevR = (prevColor >> 16) & 0xFF; int prevG = (prevColor >> 8) & 0xFF; int prevB = prevColor & 0xFF; // Compute the difference of the red, green, and blue values int diffR = abs(currR - prevR); int diffG = abs(currG - prevG); int diffB = abs(currB - prevB); // Add these differences to the running tally movementSum += diffR + diffG + diffB; // Render the difference image to the screen //diffFrame = color(diffR, diffG, diffB); diffFrame[i] = round(sqrt(diffR*diffR + diffG*diffG + diffB*diffB)); // pixels[i] = currColor; // pixels[i] = color(diffFrame[i]); // The following line is much faster, but more confusing to read //pixels[i] = 0xff000000 | (diffR << 16) | (diffG << 8) | diffB; // Save the current color into the 'previous' buffer previousFrame[i] = currColor; } // To prevent flicker from frames that are all black (no movement), // only update the screen if the image has changed. if (movementSum > 0) { updatePixels(); // println(movementSum); // Print the total amount of movement to the console } } int v = round(x+y*width); if (diffFrame[v] > 5) { if ((diffFrame[v] > 5) && (diffFrame[v] < 15)) { movementDiff = movementDiff + 3; } else if ((diffFrame[v] > 15) && (diffFrame[v] < 50)) { movementDiff = movementDiff - 3; } movementDiffNegative = (movementDiff * -1); System.out.println("the movement diff is" + movementDiff + "the movementDiffNegative is" + movementDiffNegative); //treecursion background(250); stroke(0); curlx += (radians(360./height*movementDiff)-curlx)/deley; curly += (radians(360./height*movementDiffNegative)-curly)/deley; translate(width/2,height/3*2); line(0,0,0,height/2); branch(height/4.,17); growth += (growthTarget/10-growth+1.)/deley; println(diffFrame[v]); } } void mouseWheel(int delta) { growthTarget += delta; } //treecursion void branch(float len,int num) { len *= f; num -= 1; if((len > 1) && (num > 0)) { pushMatrix(); rotate(curlx); line(0,0,0,-len); translate(0,-len); branch(len,num); popMatrix(); // pushMatrix(); // line(0,0,0,-len); // translate(0,-len); // branch(len); // popMatrix(); len *= growth; pushMatrix(); rotate(curlx-curly); line(0,0,0,-len); translate(0,-len); branch(len,num); popMatrix(); //len /= growth; } }
