SHAPE
ConformShapeToModel (Vec &b, // io
const SHAPE &Shape, // in
const ASM_MODEL &Model, // in
int iLev, // in
bool fShapeModelFinalIter) // in
{
Vec MeanShape(Model.AsmLevs[iLev].MeanShape);
// For calculations below we need to see shapes (nrows x 2) as vectors (1 x 2*nrows).
// Note that this is a "view" so if you change MeanShapeAsVec you
// are changing MeanShape too, and vice versa.
VecView MeanShapeAsVec(MeanShape.viewAsCol());
// find y, the model shape that best fits Shape
SHAPE OutShape(Shape);
int nEigs = Model.AsmLevs[iLev].nEigs;
double BMax = Model.AsmLevs[iLev].BMax;
if (fShapeModelFinalIter)
{
// final iter in main ASM search loop so loosen up the model
nEigs = Model.AsmLevs[iLev].nEigsFinal;
BMax = Model.AsmLevs[iLev].BMaxFinal;
}
ASSERT(BMax > 0);
ASSERT(nEigs > 0);
SHAPE x(Shape.nrows(), 2);
x.viewAsCol() = MeanShapeAsVec + Model.EigVecs * b; // generate a model shape x
Mat Pose(AlignShape(x, Shape));
SHAPE y(TransformShape(Shape, Pose.inverse())); // project Shape into model space
// update model params b to match y
// We limit b to ensure we stay within model limits
b = Model.EigInverse * (y.viewAsCol() - MeanShapeAsVec);
LimitB(b, Model.AsmLevs[iLev].EigVals, nEigs, BMax);
// generate OutShape from the model using our calculated b,
// and align OutShape to Shape
OutShape.viewAsCol() = Model.EigVecs * b;
OutShape = TransformShape(Model.AsmLevs[iLev].MeanShape + OutShape, Pose);
return OutShape;
}
Shape ConformShapeToMod( // Return a copy of inshape conformed to the model
VEC& b, // io: eigvec weights, 2n x 1
const Shape& inshape, // in: the current position of the landmarks
const Shape& meanshape, // in: n x 2
const VEC& eigvals, // in: neigs x 1
const MAT& eigvecs, // in: 2n x neigs
const MAT& eigvecsi, // in: neigs x 2n, inverse of eigvecs
const double bmax, // in: for LimitB
const VEC& pointweights) // in: contribution of each point to the pose
{
Shape shape(inshape.clone());
// estimate the pose which transforms the shape into the model space
// (use the b from previous iterations of the ASM)
MAT modelshape(AsColVec(meanshape) + eigvecs * b);
modelshape = DimKeep(modelshape, shape.rows, 2); // redim back to 2 columns
const MAT pose(AlignmentMat(modelshape, shape, Buf(pointweights)));
// transform the shape into the model space
modelshape = TransformShape(shape, pose.inv(cv::DECOMP_LU));
// update shape model params b to match modelshape, then limit b
b = eigvecsi * AsColVec(modelshape - meanshape);
LimitB(b, eigvals, bmax);
// generate conformedshape from the model using the limited b
// (we generate as a column vec, then redim back to 2 columns)
const Shape conformedshape(DimKeep(eigvecs * b, shape.rows, 2));
// back to image space
return JitterPointsAt00(TransformShape(meanshape + conformedshape, pose));
}
