From d60e3d11d51e5ef4efbda3bc8916dbfcb465d5a3 Mon Sep 17 00:00:00 2001
From: Tim Park <timfpark@gmail.com>
Date: Mon, 29 Jul 2013 12:54:38 -0700
Subject: [PATCH] add countNonZero to Matrix operations

---
 src/Matrix.cc | 11 +++++++++++
 src/Matrix.h  |  1 +
 test/unit.js  |  9 +++++++++
 3 files changed, 21 insertions(+)

diff --git a/src/Matrix.cc b/src/Matrix.cc
index b93c671..8cbc363 100755
--- a/src/Matrix.cc
+++ b/src/Matrix.cc
@@ -61,6 +61,7 @@ Matrix::Init(Handle<Object> target) {
 	NODE_SET_PROTOTYPE_METHOD(constructor, "absDiff", AbsDiff);
 	NODE_SET_PROTOTYPE_METHOD(constructor, "addWeighted", AddWeighted);
 	NODE_SET_PROTOTYPE_METHOD(constructor, "bitwiseXor", BitwiseXor);
+	NODE_SET_PROTOTYPE_METHOD(constructor, "countNonZero", CountNonZero);
 	NODE_SET_PROTOTYPE_METHOD(constructor, "split", Split);
 	NODE_SET_PROTOTYPE_METHOD(constructor, "canny", Canny);
     NODE_SET_PROTOTYPE_METHOD(constructor, "dilate", Dilate);
@@ -816,6 +817,16 @@ Matrix::BitwiseXor(const v8::Arguments& args) {
 	return scope.Close(v8::Null());
 }
 
+Handle<Value>
+Matrix::CountNonZero(const v8::Arguments& args) {
+	HandleScope scope;
+
+	Matrix *self = ObjectWrap::Unwrap<Matrix>(args.This());
+
+	double count = (double)cv::countNonZero(self->mat);
+	return scope.Close(v8::Number::New(count));
+}
+
 Handle<Value>
 Matrix::Split(const v8::Arguments& args) {
 	HandleScope scope;
diff --git a/src/Matrix.h b/src/Matrix.h
index 5197001..3dcb691 100755
--- a/src/Matrix.h
+++ b/src/Matrix.h
@@ -56,6 +56,7 @@ class Matrix: public node::ObjectWrap {
     JSFUNC(AbsDiff)
     JSFUNC(AddWeighted)
     JSFUNC(BitwiseXor)
+    JSFUNC(CountNonZero)
     JSFUNC(Split)
     JSFUNC(Canny)
     JSFUNC(Dilate)
diff --git a/test/unit.js b/test/unit.js
index d008508..863750c 100755
--- a/test/unit.js
+++ b/test/unit.js
@@ -216,6 +216,15 @@ vows.describe('Smoke Tests OpenCV').addBatch({
       assert.equal(xored.get(0,0), 0);
     }
 
+    , ".countNonZero": function(cv) {
+      cv.readImage("./examples/mona.png", function(err, im) {
+          assert.ok(im);
+  
+          im.convertGrayscale();
+          assert.equal(im.countNonZero(), 378000);
+      });
+    }
+
   }