1 简介
Distortion is often considered as an unfavorable factor in most image analysis. However, it is undeniable that the distortion reflects the intrinsic property of the lens, especially, the extreme wide-angle lens, which has a significant distortion. In this paper, we discuss how explicitly employing the distortion cues can detect the forgery object in distortion image and make the following contributions:
1) a radial distortion projection model is adopted to simplify the traditional captured ray-based models, where the straight world line is projected into a great circle on the viewing sphere;
2) two bottom-up cues based on distortion constraint are provided to discriminate the authentication of the line in the image;
3) a fake saliency map is used to maximum fake detection density, and based on the fake saliency map, an energy function is provided to achieve the pixel-level forgery object via graph cut. Experimental results on simulated data and real images demonstrate the performances of our method.
2 部分代码
% Demo for "Forgery Authentication in Extreme Wide-angle Lens Using Distortion Cue and Fake Saliency Map"close all; clear; clc;% Read datasavefile = 'ForensicImage/PSTest-5';orgimage = imread(strcat(savefile,'.jpg'));load(strcat(savefile,'.mat'));figure,subplot(131);imshow(orgimage);title('Forgery image');% compute the measure cueK_value=line_number:4;fake_saliency=zeros(size(orgimage,1),size(orgimage,2),'uint8');Grave_Point_x=0;Grave_Point_y=0;Grave_K=0;for i=1:line_number% the distance cueK_value(i,1)=Distance_inv(Points(((1+(i-1)*3):(3+(i-1)*3)),:),fish_x,fish_y,fish_r,1);% the volume cueK_value(i,2)=Volume_inv(Points(((1+(i-1)*3):(3+(i-1)*3)),:),fish_x,fish_y,fish_r,1);% the combine cueK_value(i,3)=Combine(K_value(i,2),K_value(i,1));% the untrustworthy likelihoodK_value(i,4)=1-0.9*exp(-(K_value(i,3)*10)^2/((0.2^2)*2));% compute the center of gravityif K_value(i,4)>0.5Grave_Point_x=Grave_Point_x+1*(Points(1+(i-1)*3,1)...+Points(2+(i-1)*3,1)+Points(3+(i-1)*3,1));Grave_Point_y=Grave_Point_y+1*(Points(1+(i-1)*3,2)...+Points(2+(i-1)*3,2)+Points(3+(i-1)*3,2));Grave_K=Grave_K+1;endfake_saliency = Line2image(fake_saliency, K_value(i,4),...Points(((1+(i-1)*3):(3+(i-1)*3)),:));endI=rgb2gray(orgimage);BW= edge(I,'canny',0.1);subplot(132);imshow(BW); title('Forgery line detection');hold on;for i=1:line_numberif K_value(i,4)>0.5 % line detection with S>0.5plot(Points((1+(i-1)*3),1),Points((1+(i-1)*3),2),'Color', [1,0,0]);plot(Points((2+(i-1)*3),1),Points((2+(i-1)*3),2),'Color', [1,0,0]);plot(Points((3+(i-1)*3),1),Points((3+(i-1)*3),2),'Color', [1,0,0]);line([Points((1+(i-1)*3),1) Points((2+(i-1)*3),1)], [Points((1+(i-1)*3),2) Points((2+(i-1)*3),2)],...'Color', [1,0,0], 'LineWidth', 3)line([Points((2+(i-1)*3),1) Points((3+(i-1)*3),1)], [Points((2+(i-1)*3),2) Points((3+(i-1)*3),2)],...'Color', [1,0,0], 'LineWidth', 3)elseplot(Points((1+(i-1)*3),1),Points((1+(i-1)*3),2),'Color', [0,1,0]);plot(Points((2+(i-1)*3),1),Points((2+(i-1)*3),2),'Color', [0,1,0]);plot(Points((3+(i-1)*3),1),Points((3+(i-1)*3),2),'Color', [0,1,0]);line([Points((1+(i-1)*3),1) Points((2+(i-1)*3),1)], [Points((1+(i-1)*3),2) Points((2+(i-1)*3),2)],...'Color', [0,1,0], 'LineWidth', 3)line([Points((2+(i-1)*3),1) Points((3+(i-1)*3),1)], [Points((2+(i-1)*3),2) Points((3+(i-1)*3),2)],...'Color', [0,1,0], 'LineWidth', 3)endend% Generate the fake saliency mapif Grave_K~=0Grave_Point_x=round(Grave_Point_x/(Grave_K*3));Grave_Point_y=round(Grave_Point_y/(Grave_K*3));fake_saliency(Grave_Point_y-10:Grave_Point_y+10,...Grave_Point_x-10:Grave_Point_x+10)=255;endthick=max(size(fake_saliency,1),size(fake_saliency,2));fake_saliency = imdilate(fake_saliency,strel('ball',round(thick/30),round(thick/30)));fake_saliency = imfilter(fake_saliency,fspecial('gaussian', [round(thick/10) round(thick/10)], round(thick/10)));fake_saliency=im2double(fake_saliency);if Grave_K~=0fake_saliency=fake_saliency.*(0.9/max(max(fake_saliency)));endsubplot(133);imshow(fake_saliency), colormap(hot); title('Fake saliency map');
3 仿真结果



4 参考文献
[1] Fu, H. , and X. Cao . "Forgery Authentication in Extreme Wide-Angle Lens Using Distortion Cue and Fake Saliency Map." IEEE Transactions on Information Forensics & Security 7.4(2012):1301-1314.
博主简介:擅长智能优化算法、神经网络预测、信号处理、元胞自动机、图像处理、路径规划、无人机等多种领域的Matlab仿真,相关matlab代码问题可私信交流。
部分理论引用网络文献,若有侵权联系博主删除。
该文提出了一种利用径向失真投影模型简化传统捕捉射线模型的方法,用于检测图像中的伪造对象。通过提供基于失真约束的两种自底向上线索来区分图像中的线条真实性,并使用伪造显著性图来最大化伪造检测密度。实验结果在模拟数据和真实图像上验证了方法的有效性。
488

被折叠的 条评论
为什么被折叠?



