Iris recognition using filters? I am implementing an iris recognition system in matlab and have performed the following steps according to an algorithm proposed in a paper


Initial image 


Median filtering 
For each row in the filtered image, assign a value of one to the pixels that have the minimum value in that row and the other pixels to zero
Again median filtering to remove white spots here and there.
States that: Get the row and column that has maximum
number of ones. Then find the center (xo, yo) and
the radii (rx, ry) as follows: xo = the index of this
column, yo = the index of this row, rx = the
number of ones in this row/2, ry = the number of
ones in this column/2


My question is how do i do step 5 in MATLAB?
Given a matrix A that consists of zeros and ones only (which you should have after step 4 of your algorithm, you could implement step 5 via the following:

% find column with the maximum number of ones. sum down the rows of the
% matrix and find the column with the largest sum
[ry,xo] = max(sum(A));
% find the corresponding row; do the same thing except sum across the
% matrix's columns
[rx,yo] = max(sum(A,2));
% the values "rx" and "ry" above contain the sums of the row and column
% (respectively) that have the maximum number of ones. divide them by
% 2 according to your algorithm in step 5
rx = rx / 2;
ry = ry / 2;


After the above (which is untested), then xo, yo, rx, and ry should be populated with the values that your algorithm indicated.