From 86d277f1b3bb93ff90840399e26d37d2db0f8c41 Mon Sep 17 00:00:00 2001
From: Salman <salman@tunacode.com>
Date: Sun, 7 Sep 2014 13:21:09 +0500
Subject: [PATCH] added image.crop(x,y,width,height) to address #150

---
 examples/convert_image.js |  3 +++
 src/Matrix.cc             | 27 +++++++++++++++++++++++++++
 src/Matrix.h              |  2 ++
 3 files changed, 32 insertions(+)

diff --git a/examples/convert_image.js b/examples/convert_image.js
index eeb88da..a0aedf0 100755
--- a/examples/convert_image.js
+++ b/examples/convert_image.js
@@ -6,9 +6,12 @@ cv.readImage("./mona.png", function(err, im) {
 				img_hsv = im.copy();
 				img_gray = im.copy();
 
+				img_crop = im.crop(50,50,250,250);
+
 				img_hsv.convertHSVscale();
 				img_gray.convertGrayscale();
 
+				img_crop.save("crop.png");
 				im.save("/tmp/nor.png");
 				img_hsv.save("/tmp/hsv.png");
 				img_gray.save("/tmp/gray.png");
diff --git a/src/Matrix.cc b/src/Matrix.cc
index c94064f..0cc7ea3 100755
--- a/src/Matrix.cc
+++ b/src/Matrix.cc
@@ -55,6 +55,8 @@ Matrix::Init(Handle<Object> target) {
 	NODE_SET_PROTOTYPE_METHOD(constructor, "pyrUp", PyrUp);
 	NODE_SET_PROTOTYPE_METHOD(constructor, "channels", Channels);
 
+	NODE_SET_PROTOTYPE_METHOD(constructor, "crop", Crop);
+
 	NODE_SET_PROTOTYPE_METHOD(constructor, "convertGrayscale", ConvertGrayscale);
 	NODE_SET_PROTOTYPE_METHOD(constructor, "convertHSVscale", ConvertHSVscale);
 	NODE_SET_PROTOTYPE_METHOD(constructor, "gaussianBlur", GaussianBlur);
@@ -306,6 +308,31 @@ Matrix::Clone(const Arguments& args){
 }
 
 
+Handle<Value>
+Matrix::Crop(const Arguments& args){
+
+	SETUP_FUNCTION(Matrix)
+
+  	if ((args.Length() == 4) && (args[0]->IsNumber()) && (args[1]->IsNumber()) && (args[2]->IsNumber()) && (args[3]->IsNumber())){
+
+  		int x = args[0]->IntegerValue();
+  		int y = args[1]->IntegerValue();
+  		int width = args[2]->IntegerValue();
+  		int height = args[3]->IntegerValue();
+
+		cv::Rect roi(x, y, width, height);
+
+		Local<Object> im_h = Matrix::constructor->GetFunction()->NewInstance();
+		Matrix *m = ObjectWrap::Unwrap<Matrix>(im_h);
+		m->mat = self->mat(roi);
+
+		return scope.Close(im_h);
+	}
+	else{
+		return scope.Close(v8::String::New("Insufficient or wrong arguments"));
+	}
+}
+
 Handle<Value>
 Matrix::Row(const Arguments& args){
 	SETUP_FUNCTION(Matrix)
diff --git a/src/Matrix.h b/src/Matrix.h
index 3331e44..ec89884 100755
--- a/src/Matrix.h
+++ b/src/Matrix.h
@@ -73,6 +73,8 @@ class Matrix: public node::ObjectWrap {
     JSFUNC(GoodFeaturesToTrack)
     JSFUNC(HoughLinesP)
 
+    JSFUNC(Crop)
+
     JSFUNC(inRange)
 
     JSFUNC(LocateROI)