# Revision history [back]

### Shape Transformers and Interfaces

Hi, I was trying to make use of the new Shape Transformers and Interfaces. Unfortunately it doesn't work as expected. To ensure not making any fancy warps and getting strange results cause of that reason I initialized a transformation where nothing at all should happen. But output for transformation for a testpoint is always [0,0] and the warped image is always completley gray. Any suggestions what could be wrong are welcome.

int main(void)
{
std::vector<cv::Point2f> points1, testpoints;
vector<DMatch> good_matches;
Mat respic, resmat;

points1.push_back(Point(0, 0)); //Corners 800x600 pic
points1.push_back(Point(799, 0));
points1.push_back(Point(799, 599));
points1.push_back(Point(0, 599));

Mat pointmatrix1(points1);

good_matches.push_back(DMatch(0, 0, 0));
good_matches.push_back(DMatch(1, 1, 0));
good_matches.push_back(DMatch(2, 2, 0));
good_matches.push_back(DMatch(3, 3, 0));

testpoints.push_back(Point(250, 250));
Mat testpointsmat(testpoints);

// Apply TPS
Ptr<ThinPlateSplineShapeTransformer> mytps = createThinPlateSplineShapeTransformer(0);
mytps->estimateTransformation(pointmatrix1, pointmatrix1, good_matches); // Using same pointmatrix nothing should change in res
mytps->applyTransformation(testpointsmat, resmat);

cout << "pointmatrix1 = " << endl << " " << pointmatrix1 << endl << endl;
cout << "testpointsmat = " << endl << " " << testpointsmat << endl << endl;
cout << "resmat = " << endl << " " << resmat << endl << endl; //Always [0,0] ?

imshow("img1", img1); // Just to see if I have a good picture

mytps->warpImage(img1, respic);

imwrite("Tranformed.png", respic);
imshow("Tranformed", respic); //Always completley grey ?

waitKey(0);

return 0;
}