1.简述
我是参考这篇博主 相机去畸变,以及双目平行校正----极线校正(二)————之双目平行校正详细过程
matlab的源码下面给出,很简单的算法结构,不做详细解说。
2.我的matlab双目极线矫正源码
clear;clc;close all;
image_left = imread('./IMAG_L1.BMP');
image_right= imread('./IMAG_R1.BMP');
[H, W, C] = size(image_left);
%内参
A_L = [ 429.99849 0.0 376.35001;
0.0 427.66238 235.38535;
0.0 0.0 1.0];
A_R = [ 422.52402 0.0 387.14095;
0.0 421.20306 210.78373;
0.0 0.0 1.0];
fx1 = A_L(1,1);
fy1 = A_L(2,2);
cx1 = A_L(1,3);
cy1 = A_L(2,3);
fx2 = A_R(1,1);
fy2 = A_R(2,2);
cx2 = A_R(1,3);
cy2 = A_R(2,3);
fx = (fx1 + fx2)/2;
fy = (fy1 + fy2)/2;
cx = (cx1 + cx2)/2;
cy = (cy1 + cy2)/2;
AA = [fx 0 cx;
0 fy cy;
0 0 1];
%外参
D_L = [ -0.02811 0.01014 -0.00971 -0.00288 0.00000 ];
D_R = [ -0.01148 -0.00157 -0.01033 0.00455 0.00000 ];
k11 = D_L(1,1);
k12 = D_L(1,2);
k13 = D_L(1,5);
p11 = D_L(1,3);
p12 = D_L(1,4);
k21 = D_R(1,1);
k22 = D_R(1,2);
k23 = D_R(1,5);
p21 = D_R(1,3);
p22 = D_R(1,4);
%旋转与平移
om = [ 0.00214 -0.03862 -0.00286] ;
R_l = rodrigues(-om/2);
R_r = R_l';
for v = 11 : H-10
for u = 26 : W-2
u1 = (u - cx)/fx;
v1 = (v - cy)/fy;
pos1 = inv(R_l)*[u1 v1 1]';
pos2 = inv(R_r)*[u1 v1 1]';
x1 = pos1(1,:)/pos1(3,:);
y1 = pos1(2,:)/pos1(3,:);
r1 = x1^2 + y1^2;
x2 = pos2(1,:)/pos2(3,:);
y2 = pos2(2,:)/pos2(3,:);
r2 = x2^2 + y2^2;
xx1 = x1*(1 + k11*r1 + k12*r1^2 + k13*r1^3) + 2*p11*x1*y1 + p12*(r1 + 2*x1^2) ;
yy1 = y1*(1 + k11*r1 + k12*r1^2 + k13*r1^3) + 2*p12*x1*y1 + p11*(r1 + 2*y1^2) ;
xx2 = x2*(1 + k21*r2 + k22*r2^2 +k23*r2^3) + 2*p21*x2*y2 + p22*(r2 + 2*x2^2) ;
yy2 = y2*(1 + k21*r2 + k22*r2^2 +k23*r2^3) + 2*p22*x2*y2 + p21*(r2 + 2*y2^2) ;
xxx1 = xx1*fx1 + cx1;
yyy1 = yy1*fy1 + cy1;
xxx2 = xx2*fx2 + cx2;
yyy2 = yy2*fy2 + cy2;
if( xxx1 > 1 && yyy1 >1 && xxx1 <= 752 && yyy1 <=480)
w1 = xxx1;
h1 = yyy1;
new_image_L(v-10,u-25)= (floor(w1+1)-w1) * (floor(h1+1)-h1) * image_left(floor(h1),floor(w1)) + (floor(w1+1)-w1) * (h1-floor(h1)) * image_left(floor(h1+1),floor(w1)) + (w1-floor(w1)) * (floor(h1+1)-h1) * image_left(floor(h1),floor(w1+1) ) + (w1-floor(w1)) * (h1-floor(h1)) * image_left(floor(h1+1),floor(w1+1));
end
if(xxx2 > 1 && yyy2 >1 && xxx2 <= 752 && yyy2 <=480)
w2 = xxx2;
h2 = yyy2;
new_image_R(v-10,u-25)= (floor(w2+1)-w2) * (floor(h2+1)-h2) * image_right(floor(h2),floor(w2)) + (floor(w2+1)-w2) * (h2-floor(h2)) * image_right(floor(h2+1),floor(w2)) + (w2-floor(w2)) * (floor(h2+1)-h2) * image_right(floor(h2),floor(w2+1) ) + (w2-floor(w2)) * (h2-floor(h2)) * image_right(floor(h2+1),floor(w2+1));
end
end
end
size(new_image_L)
size(new_image_R)
ori_image = [image_left,image_right];
cor_image = [new_image_L,new_image_R];
[e, f, g] = size(ori_image);
subplot(2,1,1);imshow(ori_image);
title('校正之前');
M = 10; % 水平分量
N = 10; % 垂直分量
lw = 0.001; % 划线宽度
mx= ones(1,M+1);
my = linspace(1,e,M+1);
% 画水平线
for k = 1:M+1
line([mx(k) f*mx(k)],[my(k) my(k)],'color','g','LineWidth',lw);
end
nx = linspace(1,f,N+1);
ny = ones(1,N+1);
% 画垂直线
for k = 1:N+1
line([nx(k) nx(k)],[ny(k) e*ny(k)],'color','g','LineWidth',lw);
end
subplot(2,1,2);imshow(cor_image);
title('校正之后');
M = 10; % 水平分量
N = 10; % 垂直分量
lw = 0.001; % 划线宽度
mx= ones(1,M+1);
my = linspace(1,e,M+1);
% 画水平线
for k = 1:M+1
line([mx(k) f*mx(k)],[my(k) my(k)],'color','g','LineWidth',lw);
end
nx = linspace(1,f,N+1);
ny = ones(1,N+1);
% 画垂直线
for k = 1:N+1
line([nx(k) nx(k)],[ny(k) e*ny(k)],'color','g','LineWidth',lw);
end
3.矫正效果图
能看出还是有误差.
4.疑惑与说明
1)om是matlab标定得到的旋转矢量矩阵,需要用 rodrigues 函数转换为旋转角度(弧度).
2)这个拆分旋转矩阵的方法我是参考matlab工具箱里面的,不知道准确性。查阅很多论文和博客,以及请教群友也没给出很好答案。这个呢我算是硬凑上去的。如有知道的朋友,麻烦留言或者私聊一下,感激不敬!!!
3)说明一下,在做畸变矫正和极线矫正时,发现我的摄像头镜头不太好,大光圈那种,录下的图片很模糊,影响精度,所以这儿换了无畸变的镜头,很清晰了。所以和前面博客图片有些出入,但不影响。使用无畸变镜头并不意味着真没畸变,只是畸变很小,所以我还是进行畸变矫正。
4)下一步呢,有可能继续用matlab做双目匹配,也有可能将现有的成果进行FPGA移植。目前呢我用zynq搭建差不多,就是卡在图像插值哪儿缓存。所以接下来的工作方向不太确定。