PS 滤镜——极坐标变换到平面坐标

%%%  极坐标到平面坐标

clc;
clear all;
close all;

addpath('E:\PhotoShop Algortihm\Image Processing\PS Algorithm');

I=imread('4.jpg');
I=double(I);

Image=I;
Info_Size=size(Image);
row=Info_Size(1);
col=Info_Size(2);
e=col/row;
R=row/2;
a=col/2;
b=row/2;

Image_new=Image;
Center_X=(col+1)/2;
Center_Y=(row+1)/2;

for i=1:row
    for j=1:col       
        r1=i*R/row;
        r2=r1*e;
        theta=j*2*pi/col;
        x1=r2*cos(theta);
        y1=r1*sin(theta);
        x=Center_X+x1;
        y=Center_Y-y1;
% % % % x=floor(x)+1;
% % % % y=floor(y)+1;
        if(x>1 && x1)
             x1=floor(x);
             y1=floor(y);
             p=x-x1;
             q=y-y1;
             Image_new(i,j,:)=(1-p)*(1-q)*Image(y1,x1,:)+p*(1-q)*Image(y1,x1+1,:)...
                            +q*(1-p)*Image(y1+1,x1,:)+p*q*Image(y1+1,x1+1,:);
        end
    end
end

figure, imshow(Image_new/255);

原图

效果图 

转载于:https://www.cnblogs.com/muyuge/p/6152349.html