Allow multiple barcodes to be decoded

.eslintrc

@@ -10,7 +10,6 @@
     "ecmaFeatures": {
         "blockBindings": true,
         "forOf": true,
-        "blockBindings": true,
         "defaultParams": true,
         "globalReturn": false,
         "modules": true,
@@ -59,7 +58,6 @@
         "comma-style": [2, "last"],
         "consistent-this": [1, "self"],
         "eol-last": 0,
-        "new-cap": 0,
         "new-parens": 2,
         "no-array-constructor": 2,
         "no-mixed-spaces-and-tabs": 2,

README.md

@@ -357,7 +357,8 @@ options within the `decoder` are for debugging/visualization purposes only.
   showPattern: false,
   readers: [
     'code_128_reader'
-  ]
+  ],
+  multiple: false
 }
 ```
 
@@ -380,6 +381,12 @@ more possible clashes, or false-positives. One should take care of the order
 the readers are given, since some might return a value even though it is not
 the correct type (EAN-13 vs. UPC-A).
 
+The `multiple` property tells the decoder if it should continue decoding after
+finding a valid barcode.  If multiple is set to `true`, the results will be 
+returned as an array of result objects.  Each object in the array will have a
+`box`, and may have a `codeResult` depending on the success of decoding the 
+individual box.
+
 The remaining properties `drawBoundingBox`, `showFrequency`, `drawScanline` and
 `showPattern` are mostly of interest during debugging and visualization.
 

package.json

@@ -11,7 +11,9 @@
     "babel-loader": "^5.3.2",
     "chai": "^3.4.1",
     "core-js": "^1.2.1",
+    "eslint": "^1.10.3",
     "grunt": "^0.4.5",
+    "grunt-cli": "^0.1.13",
     "grunt-contrib-nodeunit": "^0.4.1",
     "grunt-karma": "^0.12.1",
     "isparta-loader": "^1.0.0",
@@ -21,9 +23,8 @@
     "karma-coverage": "^0.5.2",
     "karma-mocha": "~0.2.0",
     "karma-phantomjs-launcher": "^0.2.1",
-    "karma-sinon-chai": "^1.1.0",
     "karma-sinon": "^1.0.4",
-    "karma-sinon-chai": "~0.2.0",
+    "karma-sinon-chai": "^1.1.0",
     "karma-source-map-support": "^1.1.0",
     "karma-webpack": "^1.7.0",
     "mocha": "^2.3.2",
@@ -39,7 +40,8 @@
     "test": "grunt test",
     "integrationtest": "grunt integrationtest",
     "build": "webpack && webpack --config webpack.config.min.js && grunt uglyasm && webpack --config webpack.node.config.js",
-    "watch": "webpack --watch"
+    "watch": "webpack --watch",
+    "lint": "eslint src"
   },
   "repository": {
     "type": "git",
@@ -63,7 +65,7 @@
   ],
   "author": "Christoph Oberhofer <[email protected]>",
   "license": "MIT",
-  "engines":{
+  "engines": {
     "node": ">= 4.0"
   },
   "dependencies": {

src/barcode_decoder.js

@@ -267,14 +267,27 @@ export default {
                 return decodeFromBoundingBox(box);
             },
             decodeFromBoundingBoxes: function(boxes) {
-                var i, result;
+                var i, result,
+                    barcodes = [],
+                    multiple = config.multiple;
+
                 for ( i = 0; i < boxes.length; i++) {
-                    result = decodeFromBoundingBox(boxes[i]);
-                    if (result && result.codeResult) {
-                        result.box = boxes[i];
+                    const box = boxes[i];
+                    result = decodeFromBoundingBox(box) || {};
+                    result.box = box;
+
+                    if (multiple) {
+                        barcodes.push(result);
+                    } else if (result.codeResult) {
                         return result;
                     }
                 }
+
+                if (multiple) {
+                    return {
+                        barcodes
+                    };
+                }
             },
             setReaders: function(readers) {
                 config.readers = readers;

src/quagga.js

@@ -164,14 +164,24 @@ function transformResult(result) {
         yOffset = topRight.y,
         i;
 
-    if (!result || (xOffset === 0 && yOffset === 0)) {
+    if (xOffset === 0 && yOffset === 0) {
         return;
     }
 
+    if (result.barcodes) {
+        for (i = 0; i < result.barcodes.length; i++) {
+            transformResult(result.barcodes[i]);
+        }
+    }
 
     if (result.line && result.line.length === 2) {
         moveLine(result.line);
     }
+
+    if (result.box) {
+        moveBox(result.box);
+    }
+
     if (result.boxes && result.boxes.length > 0) {
         for (i = 0; i < result.boxes.length; i++) {
             moveBox(result.boxes[i]);
@@ -195,19 +205,36 @@ function transformResult(result) {
     }
 }
 
+function addResult (result, imageData) {
+    if (!imageData || !_resultCollector) {
+        return;
+    }
+
+    if (result.barcodes) {
+        result.barcodes.filter(barcode => barcode.codeResult)
+            .forEach(barcode => addResult(barcode, imageData));
+    } else if (result.codeResult) {
+        _resultCollector.addResult(imageData, _inputStream.getCanvasSize(), result.codeResult);
+    }
+}
+
+function hasCodeResult (result) {
+    return result && (result.barcodes ?
+      result.barcodes.some(barcode => barcode.codeResult) :
+      result.codeResult);
+}
+
 function publishResult(result, imageData) {
-    if (_onUIThread) {
+    const resultToPublish = result && (result.barcodes || result);
+
+    if (result && _onUIThread) {
         transformResult(result);
-        if (imageData && result && result.codeResult) {
-            if (_resultCollector) {
-                _resultCollector.addResult(imageData, _inputStream.getCanvasSize(), result.codeResult);
-            }
-        }
+        addResult(result, imageData);
     }
 
-    Events.publish("processed", result);
-    if (result && result.codeResult) {
-        Events.publish("detected", result);
+    Events.publish("processed", resultToPublish);
+    if (hasCodeResult(result)) {
+        Events.publish("detected", resultToPublish);
     }
 }