Updated version to include Code 39 decoding

examples/file_input.html

@@ -18,6 +18,8 @@ showInMenu: false
         <input type="radio" name="reader" value="code_128" checked />
         <label>EAN</label>
         <input type="radio" name="reader" value="ean" />
+        <label>Code39</label>
+        <input type="radio" name="reader" value="code_39" />
     </fieldset>
   </div>
   <div id="result_strip">

examples/js/quagga.js

@@ -470,10 +470,11 @@ define(
             return error;
         };
 
-        BarcodeReader.prototype._nextSet = function(line) {
+        BarcodeReader.prototype._nextSet = function(line, offset) {
             var i;
 
-            for (i = 0; i < line.length; i++) {
+            offset = offset || 0;
+            for (i = offset; i < line.length; i++) {
                 if (line[i]) {
                     return i;
                 }
@@ -597,6 +598,18 @@ define(
             return result;
         };
 
+        BarcodeReader.prototype._matchRange = function(start, end, value) {
+            var i;
+
+            start = start < 0 ? 0 : start;
+            for (i = start; i < end; i++) {
+                if (this._row[i] !== value) {
+                    return false;
+                }
+            }
+            return true;
+        };
+        
         BarcodeReader.DIRECTION = {
             FORWARD : 1,
             REVERSE : -1
@@ -1409,7 +1422,7 @@ define('input_stream',["image_loader"], function(ImageLoader) {
 
         that.setInputStream = function(config) {
             _config = config;
-            video.src = config.src;
+            video.src = (typeof config.src !== 'undefined') ? config.src : '';
         };
 
         that.ended = function() {
@@ -4180,6 +4193,16 @@ define('array_helper',[],function() {
                 }
             }
             return max;
+        },
+
+        sum: function(arr) {
+            var length = arr.length,
+                sum = 0;
+
+            while(length--) {
+                sum += arr[length];
+            }
+            return sum;
         }
     };
 }); 
@@ -6416,12 +6439,213 @@ define('bresenham',[],function() {
 /* jshint undef: true, unused: true, browser:true, devel: true */
 /* global define */
 
-define('barcode_decoder',["bresenham", "image_debug", 'code_128_reader', 'ean_reader'], function(Bresenham, ImageDebug, Code128Reader, EANReader) {
+define(
+    'code_39_reader',[
+        "./barcode_reader",
+        "./array_helper"
+    ],
+    function(BarcodeReader, ArrayHelper) {
+        
+
+        function Code39Reader() {
+            BarcodeReader.call(this);
+        }
+
+        var properties = {
+            ALPHABETH_STRING: {value: "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ-. *$/+%"},
+            ALPHABET: {value: [48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 45, 46, 32, 42, 36, 47, 43, 37]},
+            CHARACTER_ENCODINGS: {value: [0x034, 0x121, 0x061, 0x160, 0x031, 0x130, 0x070, 0x025, 0x124, 0x064, 0x109, 0x049, 0x148, 0x019, 0x118, 0x058, 0x00D, 0x10C, 0x04C, 0x01C, 0x103, 0x043, 0x142, 0x013, 0x112, 0x052, 0x007, 0x106, 0x046, 0x016, 0x181, 0x0C1, 0x1C0, 0x091, 0x190, 0x0D0, 0x085, 0x184, 0x0C4, 0x094, 0x0A8, 0x0A2, 0x08A, 0x02A]},
+            ASTERISK: {value: 0x094}
+        };
+
+        Code39Reader.prototype = Object.create(BarcodeReader.prototype, properties);
+        Code39Reader.prototype.constructor = Code39Reader;
+
+        Code39Reader.prototype._toCounters = function(start, counter) {
+            var self = this,
+                numCounters = counter.length,
+                end = self._row.length,
+                isWhite = !self._row[start],
+                i,
+                counterPos = 0;
+
+            ArrayHelper.init(counter, 0);
+
+            for ( i = start; i < end; i++) {
+                if (self._row[i] ^ isWhite) {
+                    counter[counterPos]++;
+                } else {
+                    counterPos++;
+                    if (counterPos === numCounters) {
+                        break;
+                    } else {
+                        counter[counterPos] = 1;
+                        isWhite = !isWhite;
+                    }
+                }
+            }
+
+            return counter;
+        };
+
+        Code39Reader.prototype._decode = function() {
+            var self = this,
+                counters = [0,0,0,0,0,0,0,0,0],
+                result = [],
+                start = self._findStart(),
+                decodedChar,
+                lastStart,
+                pattern,
+                nextStart;
+
+            if (!start) {
+                return null;
+            }
+            nextStart = self._nextSet(self._row, start.end);
+
+            do {
+                counters = self._toCounters(nextStart, counters);
+                pattern = self._toPattern(counters);
+                if (pattern < 0) {
+                    return null;
+                }
+                decodedChar = self._patternToChar(pattern);
+                result.push(decodedChar);
+                lastStart = nextStart;
+                nextStart += ArrayHelper.sum(counters);
+                nextStart = self._nextSet(self._row, nextStart);
+            } while(decodedChar !== '*');
+            result.pop();
+
+
+
+            return {
+                code : result.join(""),
+                start : start.start,
+                end : nextStart,
+                startInfo : start,
+                decodedCodes : result
+            };
+        };
+
+        Code39Reader.prototype._patternToChar = function(pattern) {
+            var i,
+                self = this;
+
+            for (i = 0; i < self.CHARACTER_ENCODINGS.length; i++) {
+                if (self.CHARACTER_ENCODINGS[i] === pattern) {
+                    return String.fromCharCode(self.ALPHABET[i]);
+                }
+            }
+        };
+
+        Code39Reader.prototype._findNextWidth = function(counters, current) {
+            var i,
+                minWidth = Number.MAX_VALUE;
+
+            for (i = 0; i < counters.length; i++) {
+                if (counters[i] < minWidth && counters[i] > current) {
+                    minWidth = counters[i];
+                }
+            }
+
+            return minWidth;
+        };
+
+        Code39Reader.prototype._toPattern = function(counters) {
+            var numCounters = counters.length,
+                maxNarrowWidth = 0,
+                numWideBars = numCounters,
+                wideBarWidth = 0,
+                self = this,
+                pattern,
+                i;
+
+            while(numWideBars > 3) {
+                maxNarrowWidth = self._findNextWidth(counters, maxNarrowWidth);
+                numWideBars = 0;
+                pattern = 0;
+                for (i = 0; i < numCounters; i++) {
+                    if (counters[i] > maxNarrowWidth) {
+                        pattern |= 1 << (numCounters - 1 - i);
+                        numWideBars++;
+                        wideBarWidth += counters[i];
+                    }
+                }
+
+                if (numWideBars === 3) {
+                    for (i = 0; i < numCounters && numWideBars > 0; i++) {
+                        if (counters[i] > maxNarrowWidth) {
+                            numWideBars--;
+                            if ((counters[i] * 3) >= wideBarWidth) {
+                                return -1;
+                            }
+                        }
+                    }
+                    return pattern;
+                }
+            }
+            return -1;
+        };
+
+        Code39Reader.prototype._findStart = function() {
+            var self = this,
+                offset = self._nextSet(self._row),
+                patternStart = offset,
+                counter = [0,0,0,0,0,0,0,0,0],
+                counterPos = 0,
+                isWhite = false,
+                i,
+                j,
+                whiteSpaceMustStart;
+
+            for ( i = offset; i < self._row.length; i++) {
+                if (self._row[i] ^ isWhite) {
+                    counter[counterPos]++;
+                } else {
+                    if (counterPos === counter.length - 1) {
+
+                        // find start pattern
+                        if (self._toPattern(counter) === self.ASTERISK) {
+                            whiteSpaceMustStart = Math.floor(Math.max(0, patternStart - ((i - patternStart) / 4)));
+                            if (self._matchRange(whiteSpaceMustStart, patternStart, 0)) {
+                                return {
+                                    start: patternStart,
+                                    end: i
+                                };
+                            }
+                        }
+
+                        patternStart += counter[0] + counter[1];
+                        for ( j = 0; j < 7; j++) {
+                            counter[j] = counter[j + 2];
+                        }
+                        counter[7] = 0;
+                        counter[8] = 0;
+                        counterPos--;
+                    } else {
+                        counterPos++;
+                    }
+                    counter[counterPos] = 1;
+                    isWhite = !isWhite;
+                }
+            }
+            return null;
+        };
+
+        return (Code39Reader);
+    }
+);
+/* jshint undef: true, unused: true, browser:true, devel: true */
+/* global define */
+
+define('barcode_decoder',["bresenham", "image_debug", 'code_128_reader', 'ean_reader', 'code_39_reader'], function(Bresenham, ImageDebug, Code128Reader, EANReader, Code39Reader) {
     
     
     var readers = {
         code_128_reader: Code128Reader,
-        ean_reader: EANReader
+        ean_reader: EANReader,
+        code_39_reader: Code39Reader
     };
     var BarcodeDecoder = {
         create : function(config, inputImageWrapper) {
@@ -6967,7 +7191,7 @@ define('camera_access',["html_utils"], function(HtmlUtils) {
     }
 
     /**
-     * Tries to attach the camer-stream to a given video-element
+     * Tries to attach the camera-stream to a given video-element
      * and calls the callback function when the content is ready
      * @param {Object} constraints
      * @param {Object} video
@@ -7001,6 +7225,12 @@ define('camera_access',["html_utils"], function(HtmlUtils) {
         });
     }
 
+    /**
+     * Normalizes the incoming constraints to satisfy the current browser
+     * @param config
+     * @param cb Callback which is called whenever constraints are created
+     * @returns {*}
+     */
     function normalizeConstraints(config, cb) {
         var constraints = {
                 audio: false,

examples/live_w_locator.html

@@ -17,6 +17,8 @@ showInMenu: false
         <input type="radio" name="reader" value="code_128" checked />
         <label>EAN</label>
         <input type="radio" name="reader" value="ean" />
+        <label>Code39</label>
+        <input type="radio" name="reader" value="code_39" />
     </fieldset>
     <br clear="all" />
   </div>

examples/static_images.html

@@ -20,6 +20,8 @@ showInMenu: false
         <input type="radio" name="reader" value="code_128" checked />
         <label>EAN</label>
         <input type="radio" name="reader" value="ean" />
+        <label>Code39</label>
+        <input type="radio" name="reader" value="code_39" />
     </fieldset>
   </div>
   <div id="result_strip">

index.md

@@ -268,6 +268,10 @@ In case you want to take a deeper dive into the inner workings of Quagga, get to
 
 ## <a name="changelog">Changelog</a>
 
+### 2015-03-04
+- Features
+  - Added support for [Code 39][code39_wiki] barcodes
+
 ### 2015-01-21
 - Features
   - Added support for web-worker (using 4 workers as default, can be changed through `config.numOfWorkers`)
@@ -289,3 +293,4 @@ In the course of implementing web-workers some breaking changes were introduced
 [chaiUrl]: http://chaijs.com/
 [mochaUrl]: https://github.com/mochajs/mocha
 [karmaUrl]: http://karma-runner.github.io/
+[code39_wiki]: http://en.wikipedia.org/wiki/Code_39