add neural net options for switching out classifier in future

kittydar.js

@@ -6,19 +6,19 @@ if (process.arch) {   // in node
   var Canvas = (require)('canvas');
 }
 
-var network = require("./network.json");
+var network = require("./network.js");
 var net = new brain.NeuralNetwork().fromJSON(network);
 
 var params = {
   patchSize: 48,       // size of training images in px
   minSize: 48,         // starting window size
   resize: 360,         // initial image resize size in px
   scaleStep: 6,        // scaling step size in px
-  shiftBy: 4,          // px to slide window by
+  shiftBy: 6,          // px to slide window by
   overlapThresh: 0.5,  // min overlap ratio to classify as an overlap
-  minOverlaps: 8,      // minumum overlapping rects to classify as a head
+  minOverlaps: 2,      // minumum overlapping rects to classify as a head
   HOGparams: {         // parameters for HOG descriptor
-    cellSize: 4, // must divide evenly into shiftBy
+    cellSize: 6, // must divide evenly into shiftBy
     blockSize: 2,
     blockStride: 1,
     bins: 6,
@@ -33,7 +33,7 @@ var params = {
     // override if using another classifier
     var output = net.runInput(features)[0];
     return {
-      isCat: output > 0.995,
+      isCat: output > 0.999,
       value: output
     };
   }

nn-classifier.js

@@ -0,0 +1,29 @@
+/*
+  Running kittydar with these options will use the neural network backend:
+
+  var options = require("./nn-options");
+  kittydar.detectCats(canvas, options);
+ */
+var brain = require("brain");
+
+var network = require("./network.js");
+var net = new brain.NeuralNetwork().fromJSON(network);
+
+module.exports = {
+  shiftBy: 6,        // px to slide window by
+  minOverlaps: 2,    // minumum overlapping rects to classify as a head
+  HOGparams: {       // parameters for HOG descriptor
+    cellSize: 6,     // must divide evenly into shiftBy
+    blockSize: 2,
+    blockStride: 1,
+    bins: 6,
+    norm: "L2"
+  },
+  classify: function(features) {
+    var output = net.runInput(features)[0];
+    return {
+      isCat: output > 0.999,
+      value: output
+    };
+  }
+}