Analyse of MV Field by Matlab

% Function: Draw arrow array for motion vector field.
% Input:
%       fn: Filename
% Output:
%       pic:Arrow array picture.
%author:Chen Yu
%school:Carnegie Mellon University

function DarwMVField(fn)
fid=fopen(fn,'r');
if(fid == -1)
disp('Open Fail');
else
ArrayData = fscanf(fid, '%d');
Len = length(ArrayData);
%temp = zeros(ArrayData(1),ArrayData(2));
MVField = cat(2);
for i = 1:ArrayData(1)
for j = 1:ArrayData(2)
for k = 1:2
MVField(i,j, k) = ArrayData(2*((i - 1)*ArrayData(2) + j) + k);
end
end
end
%{
for i = 1:(ArrayData(1)/2)
temp1 = MVField(i,:, 1);
MVField(i,:, 1) = MVField(ArrayData(1)+1-i,:,1);
MVField(ArrayData(1)+1-i,:,1) = temp1;
temp2 = MVField(i,:, 2);
MVField(i,:, 2) = MVField(ArrayData(1)+1-i,:,2);
MVField(ArrayData(1)+1-i,:,2) = temp2;
end
%}
% (55, 40) = (x, y)
[X, Y] = meshgrid(1:1:ArrayData(2), 1:1:ArrayData(1));
%[X, Y] = meshgrid(1:1:150, 1:1:150);
hold on ;                         % 开启图形保持
xlabel('x');
ylabel('y');
title('Motion Vector Field')
set(gca,'XLim',[0 ArrayData(2)])
set(gca,'YLim',[0 ArrayData(1)])
set(gca,'YDir','reverse')

quiver(X,Y,MVField(1:ArrayData(1),1:ArrayData(2),1),MVField(1:ArrayData(1),1:ArrayData(2),2));               % 绘制梯度场
contour(X,Y,MVField(1:ArrayData(1),1:ArrayData(2),1),MVField(1:ArrayData(1),1:ArrayData(2),2));
end
end