BackgroundSubtraction – How to keep the shape with the colors

lxnr_p

Hi everybody, I need some help for a project. I'm looking for a solution since a week but nothing work, or I don't come up to do it.

So, I'm trying to remove the background of the video from the webcam and keep the object in movement with its shape and its color. There is the BackgroundSubtraction in the examples, and I could modify it a little to have a black background and the contour of the object that is draw when an object in motion is detected. But I would like we see ourself in this contour. Then, I continue my research and I find in OpenProcessing a women that done something that match the most with what i'm trying to do. And we could press space to freeze the shape that was in motion, and then we only see the shape that move (with transparency) and the one that was freezed.

What i'm trying to do is the same thing but without the image capture. I could modify it to remove the image capture but the result is not really good, cause there's no transparency (only when we move in the interstice of two shape?).

Here the original code:

/**
 * Background Subtraction 
 * by Golan Levin. 
 * 
 * Detect the presence of people and objects in the frame using a simple
 * background-subtraction technique. To initialize the background, press a key.
 */


import processing.video.*;

int numPixels;
int[] backgroundPixels;
Capture video;

void setup() {
  // Change size to 320 x 240 if too slow at 640 x 480
  size(640, 480); 

  video = new Capture(this, width, height, 24);
  numPixels = video.width * video.height;
  // Create array to store the background image
  backgroundPixels = new int[numPixels];
  // Make the pixels[] array available for direct manipulation
  loadPixels();
}

void draw() {
  video.start();
  if (video.available()) {
    video.read(); // Read a new video frame
    video.loadPixels(); // Make the pixels of video available
    // Difference between the current frame and the stored background
    int presenceSum = 0;
    for (int i = 0; i < numPixels; i++) { // For each pixel in the video frame...
      // Fetch the current color in that location, and also the color
      // of the background in that spot
      color currColor = video.pixels[i];
      color bkgdColor = backgroundPixels[i];
      // Extract the red, green, and blue components of the current pixelÕs color
      int currR = (currColor >> 16) & 0xFF;
      int currG = (currColor >> 8) & 0xFF;
      int currB = currColor & 0xFF;
      // Extract the red, green, and blue components of the background pixelÕs color
      int bkgdR = (bkgdColor >> 16) & 0xFF;
      int bkgdG = (bkgdColor >> 8) & 0xFF;
      int bkgdB = bkgdColor & 0xFF;
      // Compute the difference of the red, green, and blue values
      int diffR = abs(currR - bkgdR);
      int diffG = abs(currG - bkgdG);
      int diffB = abs(currB - bkgdB);
      // Add these differences to the running tally
      presenceSum += diffR + diffG + diffB;
      // Render the difference image to the screen
      pixels[i] = color(diffR, diffG, diffB);
      // The following line does the same thing much faster, but is more technical
      //pixels[i] = 0xFF000000 | (diffR << 16) | (diffG << 8) | diffB;
    }
    updatePixels(); // Notify that the pixels[] array has changed
    println(presenceSum); // Print out the total amount of movement
  }
}

// When a key is pressed, capture the background image into the backgroundPixels
// buffer, by copying each of the current frameÕs pixels into it.
void keyPressed() {
  video.loadPixels();
  arraycopy(video.pixels, backgroundPixels);
}

And here the one that I modified:

/**
 * Background Subtraction 
 * by Golan Levin. 
 *
 * Detect the presence of people and objects in the frame using a simple
 * background-subtraction technique. To initialize the background, press a key.
 */


import processing.video.*;

int numPixels;
int[] backgroundPixels;
Capture video;

void setup() {
  size(720, 480); 

  // This the default video input, see the GettingStartedCapture 
  // example if it creates an error
  // video = new Capture(this, 160, 120);
  video = new Capture(this, width, height);

  // Start capturing the images from the camera
  video.start();

  numPixels = video.width * video.height;
  // Create array to store the background image
  backgroundPixels = new int[numPixels];
  // Make the pixels[] array available for direct manipulation
  loadPixels();
}

void draw() {
  video.loadPixels();
  arraycopy(video.pixels, backgroundPixels);
  updatePixels(); // Notify that the pixels[] array has changed
  //println(presenceSum); // Print out the total amount of movement
  if (video.available()) {
    video.read(); // Read a new video frame
    video.loadPixels(); // Make the pixels of video available
    // Difference between the current frame and the stored background
    int presenceSum = 0;
    for (int i = 0; i < numPixels; i++) { // For each pixel in the video frame...
      // Fetch the current color in that location, and also the color
      // of the background in that spot
      color currColor = video.pixels[i];
      color bkgdColor = backgroundPixels[i];
      // Extract the red, green, and blue components of the current pixel's color
      int currR = (currColor >> 16) & 0xFF;
      int currG = (currColor >> 8) & 0xFF;
      int currB = currColor & 0xFF;
      // Extract the red, green, and blue components of the background pixel's color
      int bkgdR = (bkgdColor >> 16) & 0xFF;
      int bkgdG = (bkgdColor >> 8) & 0xFF;
      int bkgdB = bkgdColor & 0xFF;
      // Compute the difference of the red, green, and blue values
      int diffR = abs(currR - bkgdR);
      int diffG = abs(currG - bkgdG);
      int diffB = abs(currB - bkgdB);
      // Add these differences to the running tally
      // presenceSum += diffR + diffG + diffB;
      // Render the difference image to the screen
      // pixels[i] = color(diffR, diffG, diffB);
      // The following line does the same thing much faster, but is more technical
      pixels[i] = 0xFF000000 | (diffR << 16) | (diffG << 8) | diffB;
    }
  }
}

// When a key is pressed, capture the background image into the backgroundPixels
// buffer, by copying each of the current frame's pixels into it.
void keyPressed() {
}

Actually, if I can be more clear, I would like we see the object in motion in the code I modified like we see it when we press space to freeze the image. (with the transparency and the invert filter)

I really hope somebody could help me, it drives me crazy... Thanks a lot

Alexandre