Problems with interp3

Hi everybody!:

I have a matrix whose dimensions are 512x512x56(Cube_CT), every image have a voxel whose dimensions are 0.97x0.97 (mm) and the SliceThickness is 3mm, and I need that every image has a voxel with dimensions: 0.97x0.97(mm) and the SliceThickness 1mm. My code is the following:

    [m,n,p]=size(Cube_CT);
      [X,Y,Z]=meshgrid(1:m,1:n,1:p);

      voxel_x_in=InfoCT_ord{1,1}.PixelSpacing(1);
      voxel_y_in=InfoCT_ord{1,1}.PixelSpacing(2);
      voxel_z_in=InfoCT_ord{1,1}.SliceThickness;

      voxel_x_out=InfoCT_ord{1,1}.PixelSpacing(1);
      voxel_y_out=InfoCT_ord{1,1}.PixelSpacing(2);
      voxel_z_out=1;

      xx=(voxel_x_out/voxel_x_in:voxel_x_out/voxel_x_in:m);
      yy=(voxel_y_out/voxel_y_in:voxel_y_out/voxel_y_in:n);
      zz=(voxel_z_out/voxel_z_in:voxel_z_out/voxel_z_in:p);

      [Xq,Yq,Zq]=meshgrid(xx,yy,zz);

      CubeCT_inter=interp3(X,Y,Z,Cube_CT,Xq,Yq,Zq,'cubic');

But when I execute this code, all components of the first image and second image are NaN. I don't understand where is the problem.

Thanks!

Answer 1

[Walter Roberson]

I recommend you use linspace() instead of the colon operator to build the xx, yy, zz

[Francisco Javier Vilchez Torralba]

Hi Walter, thanks for your answer but I still have the same problem using linspace:

    [m,n,p]=size(Cubo_CT);
    [X,Y,Z]=meshgrid(1:m,1:n,1:p);

    voxel_x_in=InfoCT_ord{1,1}.PixelSpacing(1);
    voxel_y_in=InfoCT_ord{1,1}.PixelSpacing(2);
    voxel_z_in=InfoCT_ord{1,1}.SliceThickness;

    voxel_x_out=InfoCT_ord{1,1}.PixelSpacing(1);
    voxel_y_out=InfoCT_ord{1,1}.PixelSpacing(2);
    voxel_z_out=1;

    xx=linspace(voxel_x_out/voxel_x_in,m,m);
    yy=linspace(voxel_y_out/voxel_y_in,n,n);
   zz=linspace(voxel_z_out/voxel_z_in,p,p/(voxel_z_out/voxel_z_in));

    [Xq,Yq,Zq]=meshgrid(xx,yy,zz);

    CuboCT_inter=interp3(X,Y,Z,Cubo_CT,Xq,Yq,Zq,'cubic');

[Walter Roberson]

Which is the "first" image, and which is the "second" image?