Auteur : delon

/// Transport 1D

function [iX,iY] = transport1D(X,Y)
 [Xs,iX] = gsort(X,'g','i'); // on a Xs = X(iX)
 [Ys,iY] = gsort(Y,'g','i');
endfunction


// Calcule l'assignent en 2D et evalue le coût total du transport

function [Z,c]=transport2D(X,Y,N,e) 
// X et Y deux nuages de points en 2D ; matrice 2 colonnes et n lignes. La fonction renvoie un nuage de points Z qui est obtenu par déplacement de X vers les points de Y.
 
  theta = %pi/2*(2*rand(N,1)-1);
  Z=X;
  for k=1:N
    utheta = [cos(theta(k));sin(theta(k))];
    Zt = Z*utheta;
    Yt = Y*utheta;
    [iZ,iY] = transport1D(Zt,Yt);
    Z(iZ,:) = Z(iZ,:)+e*(Yt(iY)-Zt(iZ))*utheta';
    D=sqrt(sum((Z(iZ,:)-Y(iY,:)).^2,2));
   if (max(D)<1D-05) then
      mprintf('stop a k=%d\n',k);
      break;
    end
  end
 c = sum(sum((X(iZ,:)-Y(iY,:)).^2,2))
endfunction

• Correction pour le TP Edition d’images

• ////////////////////////////////////////////////////////////////////
  // Function COLOR_POISSON 
  // Take two color images u and v and a binary mask. The image //v is assumed to be smaller than u. First a subimage of u 
  // with the size of v is extracted at (x,y). Then, we copy the // part of v corresponding to the mask to this subimage of u, // and then u is reformed. 
  // Author : Julie Delon, 2015. 
  ////////////////////////////////////////////////////////////////////
  
  // Input parameters 
  // - image u (large image)
  // - image v (small image with portion to be copied in u)
  // - mask (binary mask)
  // - (x,y) integers, position in u where a portion of v must 
  // be copied
  
  // Output :
  // - image out containing u and a portion of v cloned by 
  // Poisson Editing
  
  function out = color_poisson(u, v, mask, x, y, niter)
   [nr,nc] = size(v(:,:,1));
   ucrop = u(x:x+nr-1,y:y+nc-1,:); 
  
   for i = 1:3
   tmp(:,:,i) = poisson(ucrop(:,:,i),v(:,:,i),mask,niter);
   end
  
   out = u;
   out(x:x+nr-1,y:y+nc-1,:) = tmp;
   out = max(min(out,255),0);
  
  endfunction
  
  // Poisson editing for gray level images
  function out = poisson(u, v, mask, niter)
  
   f = u.*(1-mask) + v.*mask;
   K=[0,1,0;1,0,1;0,1,0];
   lapv = laplacien(v);
   
   for k = 1:niter
   Kf = conv2(f,K,'same');
   f(mask) = 1/4*(Kf(mask) + lapv(mask));
   end
  
   out = f;
  endfunction
  
  // Compute the laplacian of an image u
  function lap = laplacien(u)
  
   [ud,ub,ug,uh] = imdiff(u);
   lap = ud + ub + ug + uh;
  
  endfunction
  
  
  function [ud,ub,ug,uh] = imdiff(u)
  
   Kd = [ 0,1, -1 ];
   Kb = [ 0;1; -1 ];
   Kg = [ -1,1, 0 ];
   Kh = [ -1;1; 0 ];
  
   ud = conv2(u,Kd,'same');
   ub = conv2(u,Kb,'same');
   ug = conv2(u,Kg,'same');
   uh = conv2(u,Kh,'same');
  
  endfunction