Question

在图像配准的上下文中，我必须计算两个图像的联合直方图，即每个直方图（i，j）包含在第一个图像中强度为i而在第二个图像中为j的像素数。

要做到这一点，我循环强度：

clear all; close all; clc

M = 1024;
N = 1024;

world_map=NaN(M,N,2);

rail_1 = rgb2gray(imread('img2.bmp'));

% Initial misregistration
dx = 12;
dy = 15;

[M1,N1] = size(rail_1);

% Center the 1st image on the world_map first layer
world_map(floor(M/2-M1/2):floor(M/2+(M1/2-1)),floor(N/2-N1/2):floor(N/2+(N1/2-1)),1) = rail_1;

% Translate the same image on the world_map second layer
world_map(floor(M/2-M1/2-dx):floor(M/2+(M1/2-1-dx)),floor(N/2-N1/2-dy):floor(N/2+(N1/2-1)-dy),2) = rail_1;


figure
h1=imagesc(world_map(:,:,1));
hold on
h2=imagesc(world_map(:,:,2));
set(h2,'AlphaData',0.5)
colormap gray

% find the overlapping area of the two images
overlap = find(~isnan(world_map(:,:,1)) & ~isnan(world_map(:,:,2)));
rail_1 = world_map(:,:,1);
rail_2 = world_map(:,:,2);

% compute the joint histogram (we here suppose that we have 256 gray level)
histo = zeros(256,256);

for i=1:256
    for j=1:256

        histo(i,j) = numel(find(rail_1(overlap)==i-1 & rail_2(overlap)==j-1));

    end
end

然而，这样的算法对于我的项目来说太慢了，我试图在没有for循环的情况下做到这一点，但到目前为止，我还没有找到任何解决方案来解决我的问题。

我希望你们能帮助我解决它;）

快速计算两幅图像的联合直方图

0 个答案: