代码引用自博客:
http://blog.chinaaet.com/helimin/p/5100018184
双边滤波器函数代码如下:
function B = bfilter2(A,w,sigma)
%A为给定图像,归一化到[0,1]的double矩阵
%W为双边滤波器(核)的边长/2
%定义域方差σd记为SIGMA(1),值域方差σr记为SIGMA(2)
% This function implements 2-D bilateral filtering using
% the method outlined in:
%
% C. Tomasi and R. Manduchi. Bilateral Filtering for
% Gray and Color Images. In Proceedings of the IEEE
% International Conference on Computer Vision, 1998.
%
% B = bfilter2(A,W,SIGMA) performs 2-D bilateral filtering
% for the grayscale or color image A. A should be a double
% precision matrix of size NxMx1 or NxMx3 (i.e., grayscale
% or color images, respectively) with normalized values in
% the closed interval [0,1]. The half-size of the Gaussian
% bilateral filter window is defined by W. The standard
% deviations of the bilateral filter are given by SIGMA,
% where the spatial-domain standard deviation is given by
% SIGMA(1) and the intensity-domain standard deviation is
% given by SIGMA(2).
%
% Douglas R. Lanman, Brown University, September 2006.
% [email protected], http://mesh.brown.edu/dlanman
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Pre-process input and select appropriate filter.
% Verify that the input image exists and is valid.
if ~exist('A','var') || isempty(A)
error('Input image A is undefined or invalid.');
end
if ~isfloat(A) || ~sum([1,3] == size(A,3)) || ...
min(A(:)) < 0 || max(A(:)) > 1
error(['Input image A must be a double precision ',...
'matrix of size NxMx1 or NxMx3 on the closed ',...
'interval [0,1].']);
end
% Verify bilateral filter window size.
if ~exist('w','var') || isempty(w) || ...
numel(w) ~= 1 || w < 1 %计算数组中的元素个数
w = 5;
end
w = ceil(w); %大于w的最小整数
% Verify bilateral filter standard deviations.
if ~exist('sigma','var') || isempty(sigma) || ...
numel(sigma) ~= 2 || sigma(1) <= 0 || sigma(2) <= 0
sigma = [3 0.1];
end
% Apply either grayscale or color bilateral filtering.
if size(A,3) == 1 %如果输入图像为灰度图像,则调用灰度图像滤波方法
B = bfltGray(A,w,sigma(1),sigma(2));
else %如果输入图像为彩色图像,则调用彩色图像滤波方法
B = bfltColor(A,w,sigma(1),sigma(2));
end
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Implements bilateral filtering for grayscale images.
function B = bfltGray(A,w,sigma_d,sigma_r)
% Pre-compute Gaussian distance weights.
[X,Y] = meshgrid(-w:w,-w:w);
%创建核距离矩阵,e.g.
% [x,y]=meshgrid(-1:1,-1:1)
%
% x =
%
% -1 0 1
% -1 0 1
% -1 0 1
%
%
% y =
%
% -1 -1 -1
% 0 0 0
% 1 1 1
%计算定义域核
G = exp(-(X.^2+Y.^2)/(2*sigma_d^2));
% Create waitbar.计算过程比较慢,创建waitbar可实时看到进度
h = waitbar(0,'Applying bilateral filter...');
set(h,'Name','Bilateral Filter Progress');
% Apply bilateral filter.
%计算值域核H 并与定义域核G 乘积得到双边权重函数F
dim = size(A); %得到输入图像的width和height
B = zeros(dim);
for i = 1:dim(1)
for j = 1:dim(2)
% Extract local region.
iMin = max(i-w,1);
iMax = min(i+w,dim(1));
jMin = max(j-w,1);
jMax = min(j+w,dim(2));
%定义当前核所作用的区域为(iMin:iMax,jMin:jMax)
I = A(iMin:iMax,jMin:jMax); %提取该区域的源图像值赋给I
% Compute Gaussian intensity weights.
H = exp(-(I-A(i,j)).^2/(2*sigma_r^2));
% Calculate bilateral filter response.
F = H.*G((iMin:iMax)-i+w+1,(jMin:jMax)-j+w+1);
B(i,j) = sum(F(:).*I(:))/sum(F(:));
end
waitbar(i/dim(1));
end
% Close waitbar.
close(h);
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Implements bilateral filter for color images.
function B = bfltColor(A,w,sigma_d,sigma_r)
% Convert input sRGB image to CIELab color space.
if exist('applycform','file')
A = applycform(A,makecform('srgb2lab'));
else
A = colorspace('Lab<-RGB',A);
end
% Pre-compute Gaussian domain weights.
[X,Y] = meshgrid(-w:w,-w:w);
G = exp(-(X.^2+Y.^2)/(2*sigma_d^2));
% Rescale range variance (using maximum luminance).
sigma_r = 100*sigma_r;
% Create waitbar.
h = waitbar(0,'Applying bilateral filter...');
set(h,'Name','Bilateral Filter Progress');
% Apply bilateral filter.
dim = size(A);
B = zeros(dim);
for i = 1:dim(1)
for j = 1:dim(2)
% Extract local region.
iMin = max(i-w,1);
iMax = min(i+w,dim(1));
jMin = max(j-w,1);
jMax = min(j+w,dim(2));
I = A(iMin:iMax,jMin:jMax,:);
% Compute Gaussian range weights.
dL = I(:,:,1)-A(i,j,1);
da = I(:,:,2)-A(i,j,2);
db = I(:,:,3)-A(i,j,3);
H = exp(-(dL.^2+da.^2+db.^2)/(2*sigma_r^2));
% Calculate bilateral filter response.
F = H.*G((iMin:iMax)-i+w+1,(jMin:jMax)-j+w+1);
norm_F = sum(F(:));
B(i,j,1) = sum(sum(F.*I(:,:,1)))/norm_F;
B(i,j,2) = sum(sum(F.*I(:,:,2)))/norm_F;
B(i,j,3) = sum(sum(F.*I(:,:,3)))/norm_F;
end
waitbar(i/dim(1));
end
% Convert filtered image back to sRGB color space.
if exist('applycform','file')
B = applycform(B,makecform('lab2srgb'));
else
B = colorspace('RGB<-Lab',B);
end
% Close waitbar.
close(h);
调用方法示例:
Image_pri = imread('academy.jpg');
Image_normalized = im2double(Image_pri);
w = 5; %窗口大小
sigma = [3 0.1]; %方差
Image_bf = bfilter2(Image_normalized,w,sigma);
特此感谢原博主!
在复现cifar10_inception10.py的时候,考虑到利用在线下载的方式导入数据的方式对国内用户不太友好。决定采用先到网站下载数据集文件,然后离线导入数据。
关于如何正确解决离线导入数据的问题,这一篇博客有很好的解决方法:
https://blog.csdn.net/weixin_45868601/article/details/105231538
找到了一篇很好的博客,文章的难度是渐进的,到后面可能需要一定的数学基础,但是我很喜欢他在文中给出的几个概念的例子。
链接如下:
https://baijiahao.baidu.com/s?id=162790571049
这个网站给出一个简单图片分类神经网络。特别的是,它将数据从原始图片到最后的分类标签的流图可视化,你可以看到每一个在不同的pading,不同的步长等参数下卷积块是怎么移动的。以及池化层是如何缩减数据的,激活函数的映射关系是怎样、数据尺寸是怎样发生变化的。非常直观的一个学习CNN工具。
https://poloclub.github.io/cnn-explainer/
https://www.cnblogs.com/wj-1314/p/9579490.html
https://blog.csdn.net/z_h_s/article/details/41575761
https://blog.csdn.net/yukinoai/article/details/99715227
https://blog.csdn.net/iteye_3224/article/details/82400727?utm_medium=distribute.pc_relevant_t0.none-task-blog-BlogCommendFromMachineLearnPai2-1.nonecase&depth_1-utm_source=distribute.pc_relevant_t0.none-task-blog-BlogCommendFromMachineLearnPai2-1.nonecase
https://www.pdf365.cn/
现在百度出来的结果都是五花八门的商业广告,一言不合就让你冲会员,这是一个少有的能用的免费软件。
I =imread('C:\Users\wangd\Desktop\in000155.jpg');
I1 = rgb2gray(I);
subplot(1,2,1);imshow(I1);
fftI1=fft2(I1);
sfftI1=fftshift(fftI1);
RR1=real(sfftI1);
II1=imag(sfftI1);
A1=sqrt(RR1.^2+II1.^2);
A1=(A1-min(min(A1)))/(max(max(A1))-min(min(A1)))*225;%归一化
subplot(1,2,2);imshow(A1);
批量处理代码的注释操作。