fixed Mat::Mat(const IplImage*, bool) constructor (ticket #487). fixed the bayer demosaicing part in the new cv::cvtColor implementation

modules/core/src/matrix.cpp

@@ -82,7 +82,7 @@ Mat::Mat(const IplImage* img, bool copyData)
     if( copyData )
     {
         Mat m = *this;
-        rows = cols = 0;
+        release();
         if( !img->roi || !img->roi->coi ||
             img->dataOrder == IPL_DATA_ORDER_PLANE)
             m.copyTo(*this);

modules/imgproc/src/color.cpp

@@ -2619,6 +2619,7 @@ void cvtColor( const Mat& src, Mat& dst, int code, int dcn )
             
         case CV_BayerBG2BGR: case CV_BayerGB2BGR: case CV_BayerRG2BGR: case CV_BayerGR2BGR:
         case CV_BayerBG2BGR_VNG: case CV_BayerGB2BGR_VNG: case CV_BayerRG2BGR_VNG: case CV_BayerGR2BGR_VNG:
+            if(dcn <= 0) dcn = 3;
             CV_Assert( scn == 1 && dcn == 3 && depth == CV_8U );
             dst.create(sz, CV_8UC3);