Identification: QRCode and RFID

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Bar Code

We are using the pattern recognition every day in our life: bar code. When you go shopping, bar code; When you go club with membership, bar code.

Bar Code is simply a pattern of dark and light lines or cells used to encode an alphanumeric string. A scanner read the "image" and send it to the computer to interpreting the widths of the light and dark bands as zeros or ones. Of course, it is done by the photodiode, it is far away from what we will use: QRCode.

Different kinds of pattern recognition

We have many kinds of pattern recognition, a face detection is one of them.

face recognition

Road Sign recognition

You may tried Reatable in Microwave International New Media Arts festival 2007 before. The object is sticked by some pattern on the bottom. This is exactly the pattern recognition

By recognizing the pattern, the computer can identify each of them.

We are going to try this in the class. Instead, we are trying a easiler one, but very popular in Japan: QRCode.

QRCode: 2 deminsional bar code

QR stands for Quick Response. It is created in Japan originally for tracking the vehicle parts. But you can see it is attached to every single items in Japan everywhere like magazine, product, even can use QRCode to pay bill in shops.

It is kind of the optical way to do the pattern recognition. If you have your mobile phone a Japan version or from Japan Brand, most of them has a QRCode reader as most of the mobile phone comes with camera. Even the JAVA platform J2ME has a library to read the QRCode.

QRCode for our course web

The above QRCode is representing the URL of our course web. If you have a mobile phone with QRCode reader, just simply try it and you will see the web address.

Now, let's try it in Processing.

Daniel Shiffman has made a library for Processing: pqrcode. http://www.shiffman.net/p5/pqrcode/. Just simply download the library and put into Processing.

Before you want to play with QRCode, of course you need to generate the QRCode. Here is the online QRCode generator:

http://qrcode.kaywa.com/

pqrcode Library

There is a class "Decoder" , and it include all the function you need to analyis the QRCode.

Decoder decoder;


void setup() {
  decoder = new Decoder(this);
}

PImage img = loadImage("abc.jpg");  
decoder.decodeImage(img);

And just like movie Library and serial library, it has a event. It helps to feedback when the decoder object finishes

void decoderEvent(Decoder decoder) {    
  String statusMsg = decoder.getDecodedString();    
  println(statusMsg);  
}

The getDecodedString help to feedback the status of the decoder, like whether it is success or not.

decoder.decoding() is a boolean checking whether the decoder is decoding the image.

decoder.getImage() is a PImage that is the image the decoder is using.

Now I give you the structure here and you finish up by yourself.

import processing.video.*;
import pqrcode.*;


Capture video;
String status = " "
Decoder decoder


void setup() {
  size(???,???);
  video = new Capture(this, ???, ???, 30);
  decoder = new Decoder(this);

}


void draw() {
  background(0);
  image(video,0,0);
  
  if (decoder.decoding()) {
    PImage vv = decoder.getImage();
    image(vv, 0,0, vv.width/4, vv.height/4);

  }

}


void decoderEvent(Decoder decoder) {    
  String statusMsg = decoder.getDecodedString();    
  println(statusMsg);  
}


void captureEvent(Capture video) {
  video.read();
}

For this keyReleased, modify it by yourself to fit your case.

void keyReleased() {
  switch(key) {
  case ' ':
    PImage savedFrame = createImage(video.width, 
      video.height, RGB);
    savedFrame.copy(video,0,0,video.width,video.height,
      0,0,video.width, video.height);
    savedFrame.updatedPixels();
    decoder.decodeImage(???);
    break;
  case 'q':
    PImage testFrame = loadImage("?????");
    decoder.decodeImage(???);
    break;

}

Case Studies

The voice of the street: The voice of the street have provided a service for street artists. Combining street art, QR codes and Google Maps the service allows street artists to communicate with the viewer and visa versa.

Pet Shop Boys - MV - Integral

ConQwest

http://playareacode.com/work/conqwest/

Radio Frequency Identification: RFID

"Radio-frequency identification (RFID) is an automatic identification method, relying on storing and remotely retrieving data using devices called RFID tags or transponders.

An RFID tag is an object that can be applied to or incorporated into a product, animal, or person for the purpose of identification using radiowaves. Some tags can be read from several meters away and beyond the line of sight of the reader.

Most RFID tags contain at least two parts. One is an integrated circuit for storing and processing information, modulating and demodulating a (RF) signal, and other specialized functions. The second is an antenna for receiving and transmitting the signal. A technology called chipless RFID allows for discrete identification of tags without an integrated circuit, thereby allowing tags to be printed directly onto assets at a lower cost than traditional tags."

Here in Hong Kong, we have a very great RFID system around us everyday: Octopus Card!

Another lovely RFID application in Hong Kong is Autoroll

RFID and Art

By using RFID, there are many interactive art interact with their audience. Here is some of the references.

"RFID Light Sequencer"
2006
ISHIBASHI Motoi+MANABE Daito
http://www.ntticc.or.jp/Archive/2006/Kidsprogram/Work/RFID.html

"iTea"
David Kousemaker
http://www.mediamatic.net/artefact-22745-en.html

Straitjacket Embrace!
David Kousemaker
http://www.lancelmaat.nl/1samen/StraitjacketEmbrace/StraitJacket.html

"Transmission"
Meghan Trainor
http://meghantrainor.com/portfolio/03_nerd/003_nerd.html

"Filter"
Meghan Trainor
http://meghantrainor.com/portfolio/03_nerd/003_nerd.html

"ET"
Yuichiro Katsumoto

Extension of "Amagatana"

S.U.I. -Smart Urban Intelligence-
2006
computer, video projector, stereo speakers, smartcard reader & smart cards
C & Java with JMF, JSAPI
Prix Ars Electronica 2006, Honorary Mention Interactive Art
Ryota Kimura

RFID Snakes and Ladders

Arphield Recordings

Zapped! (http://www.preemptivemedia.net/)

Reverse Engineering: RFID Killer!!!!!

Google RFID Zapper!

HOWTO turn a disposable camera into an RFID-killer

RFID with Arduino and Processing

And it is your time to make it. Instead, you just simply need the Arduinio as an input device. I should say just use the serial communication of Arduino, and nothing more. So you don't even need to program the Arduino, but just simply program the client program (reading program), may be, in Processing.

Let's see which devices we will use:

ID Innovations ID12 Reader

RFID Tag

ID12 Breakout (Optional)

Even ID12 Breakout is cheap and useful, but it is just out of stock when we order the equipment and parts.
So you need to hand made this 2mm legs to fit the breadboard.

This is the datasheet of ID12, let's take a look.

Before you do the program in Processing, we must need to know the specification of the RFID Tag.Let's take a look now.

The format of the tag is:
STX (ASCII02) + 32 bit ID + ETX (ASCII03)

So you are receiving this information from the RFID Tag Reader.

import processing.serial.*;


Serial myPort;      
String tagID = "";  

void setup() {
   size(600,200);
   String portnum = Serial.list()[?];
   myPort = new Serial(this, portnum, 9600);
   myPort.buffer(16);
   PFont myFont = createFont(PFont.list()[2], 24);
   textFont(myFont);
}

                

void draw() {
  background(0);
  text(tagID, width/4, height/2 - 24);
}

                

void serialEvent(Serial myPort) {
  String inputString = myPort.readString();
  tagID = parseString(inputString);
}

                

String parseString(String thisString) {
  String tagString = ""; 
   
  // first character of the input:
  char firstChar = thisString.charAt(0);

  // last character of the input:
  char lastChar = thisString.charAt(thisString.length() -1);

  // if the first char is STX (0x02) and the last char
  // is ETX (0x03), then put the next ten bytes
  // into the tag string:
  if ((firstChar == 0x02) && (lastChar == 0x03)) {
    tagString = thisString.substring(1, 11);
  }

  return tagString;
}

                

Class Works: RFID Trigger Big Load Device

Now you can grab the unique ID of the RFID Tag from the reader. Can you do something with this information?

Okay, you can take some time to think about the interaction.

Here is a very little suggestion:

Remember we can use the Relay box to trigger some high load device like a Desktop Light? It just like something Home Automation: When your is RFID reconginzed Door, once you use the RFID to enter the room, the system knows who you are. Then the system will help you to trigger something like the TV.