how can i zero pad of an image(vein) to make it look like a cylinder

I have an image that i want to pad the volume until it looks like a cylinder! Then when i rotate it by 90 deg it wont look like a lot of long lines but only a lot of short lines.

[Nikhil Sonavane]

Can you explain your query is a well defined way?

[Oluwatobi Adeyemi]

i have an MIP image i want to rotate but i want it to look more like a cylinder instead of a line when i rotate it

Answer 1

[Nikhil Sonavane]

If you have the Image Processing ToolBox you can use the function PADARRAY. For example if I wanted to pad 2 zeroes around the matrix:

A =   [1 2; 3 4];
B =   [5 6; 7 8];
C =   cat(3,A,B);     % 3D matrix
D =   padarray(C,[3 3 3],0,'both');

If you do not have the toolbox you could work around by by writing a few extra lines of code:

A =   [1 2; 3 4];
B =   [5 6; 7 8];
C =   cat(3,A,B);     % 3D matrix

vec= size(C);           %Storing the dimensions of the a3d  matrix
vec= vec+4;            %Increasing the dimensions depending upon the number of zeroes to be padded.

paddedMatrix  =  zeros(vec);    %Creating an empty matrix with new dimensions 
paddedMatrix(3:end-2,3:end-2,3:end-2)=C;  %Putting C into the empty matrix.

You can also refer to the documentation of Volume Viewer App if it helps resolve your query.

[Oluwatobi Adeyemi]

the volume viewers app really help thanks