% Read two images %image1 = imread('1.png'); %image2 = imread('2.png'); image1 = imread('40.bmp'); image2 = imread('乙醇.bmp'); % Down-sample the image to half its original resolution downsampled_image1 = imresize(image1, 0.1); downsampled_image2 = imresize(image2, 0.1); % Convert images to grayscale image1 = rgb2gray(downsampled_image1); image2 = rgb2gray(downsampled_image2); % Convert images to double precision for computations image1 = double(image1); image2 = double(image2); % Determine size of images [n, m] = size(image1); % Initialize matrices for displacement fields u = zeros(n, m); v = zeros(n, m); % Set window size for correlation (odd number to have a central pixel) window_size = 15; half_window_size = (window_size-1)/2; % You need to initialize these variables before the loop uTemp = zeros(n, m); vTemp = zeros(n, m); for i = 1+half_window_size : n-half_window_size fprintf('The value of i is: %d\n', i); parfor j = 1+half_window_size : m-half_window_size fprintf('The value of j is: %d\n', j); % Extract sub-window from image1 sub_window1 = image1(i-half_window_size : i+half_window_size, j-half_window_size : j+half_window_size); % Skip this sub-window if all its values are the same if numel(unique(sub_window1)) == 1 continue; end % Correlate this with image2 within a search area (here, the whole image) correlation = normxcorr2(sub_window1, image2); % Find the peak correlation [ypeak, xpeak] = find(correlation == max(correlation(:))); % If there are multiple, just take the first one ypeak = ypeak(1); xpeak = xpeak(1); % Compute displacements (be careful about off-by-one due to zero-based and one-based indexing) uTemp(i,j) = ypeak - i; vTemp(i,j) = xpeak - j; end end % Copy the temporary variables back to the original ones after the loop u = uTemp; v = vTemp; % Flatten the images into 1D arrays image1_1D = image1(:); image2_1D = image2(:); % Compute the correlation coefficient correlationCoefficient = corrcoef(image1_1D, image2_1D); % The correlation coefficient is the value at position (1,2) or (2,1) in the output matrix correlationCoefficient = correlationCoefficient(1,2); fprintf('The value of correlationCoefficient is: %d\n', correlationCoefficient); % Display original images and displacement field figure, subplot(1,3,1), imshow(image1, []), title('Image 1'); subplot(1,3,2), imshow(image2, []), title('Image 2'); subplot(1,3,3), quiver(u, v), title('Displacement Field');

这段代码是一个基于互相关的图像位移估计算法的实现。这个算法的基本思路是在一个图像中选取一个子窗口，在另一个图像中搜索与之最相似的子窗口，通过计算它们之间的位移来估计图像的位移。具体实现中，首先读取两张图像，并对它们进行降采样和灰度化处理。然后，通过计算互相关来找到最相似的子窗口，并计算它们之间的位移。最后，将位移场可视化并计算两张图像的相关系数。

代码中的parfor循环是一个并行循环，用于加速计算。它会自动地将循环中的任务分配到多个处理器上并行执行。在这个例子中，它会将每个像素的处理任务分配到多个处理器上并行执行，以提高计算速度。

相关问题

（1）设计MATLAB图形界面，包括参考影像、带配准影像文件读取，控制点存储，配准后的影像写入等功能。 （2）根据课堂讲授的关于人工选取控制点的配准方法，设计基于人工选取控制点的配准程序； （3）研究基于Harris角点、相关系数法等遥感影像配准方法，设计自动提取控制点，并实现遥感影像配准。

以下是基于MATLAB图形界面的遥感图像配准程序代码：

function varargout = imageRegistrationGUI(varargin)
% IMAGE REGISTRATION GUI MATLAB code for imageRegistrationGUI.fig
%      IMAGE REGISTRATION GUI, by itself, creates a new IMAGE REGISTRATION GUI or raises the existing
%      singleton*.
%
%      H = IMAGE REGISTRATION GUI returns the handle to a new IMAGE REGISTRATION GUI or the handle to
%      the existing singleton*.
%
%      IMAGE REGISTRATION GUI('CALLBACK',hObject,eventData,handles,...) calls the local
%      function named CALLBACK in IMAGE REGISTRATION GUI.M with the given input arguments.
%
%      IMAGE REGISTRATION GUI('Property','Value',...) creates a new IMAGE REGISTRATION GUI or raises the
%      existing singleton*.  Starting from the left, property value pairs are
%      applied to the GUI before imageRegistrationGUI_OpeningFcn gets called.  An
%      unrecognized property name or invalid value makes property application
%      stop.  All inputs are passed to imageRegistrationGUI_OpeningFcn via varargin.
%
%      *See GUI Options on GUIDE's Tools menu.  Choose "GUI allows only one
%      instance to run (singleton)".
%
% See also: GUIDE, GUIDATA, GUIHANDLES

% Edit the above text to modify the response to help imageRegistrationGUI

% Last Modified by GUIDE v2.5 29-Jun-2021 16:31:49

% Begin initialization code - DO NOT EDIT
gui_Singleton = 1;
gui_State = struct('gui_Name',       mfilename, ...
                   'gui_Singleton',  gui_Singleton, ...
                   'gui_OpeningFcn', @imageRegistrationGUI_OpeningFcn, ...
                   'gui_OutputFcn',  @imageRegistrationGUI_OutputFcn, ...
                   'gui_LayoutFcn',  [] , ...
                   'gui_Callback',   []);
if nargin && ischar(varargin{1})
    gui_State.gui_Callback = str2func(varargin{1});
end

if nargout
    [varargout{1:nargout}] = gui_mainfcn(gui_State, varargin{:});
else
    gui_mainfcn(gui_State, varargin{:});
end
% End initialization code - DO NOT EDIT


% --- Executes just before imageRegistrationGUI is made visible.
function imageRegistrationGUI_OpeningFcn(hObject, eventdata, handles, varargin)
% This function has no output args, see OutputFcn.
% hObject    handle to figure
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)
% varargin   command line arguments to imageRegistrationGUI (see VARARGIN)

% Choose default command line output for imageRegistrationGUI
handles.output = hObject;

% Update handles structure
guidata(hObject, handles);

% UIWAIT makes imageRegistrationGUI wait for user response (see UIRESUME)
% uiwait(handles.imageRegistrationGUI);


% --- Outputs from this function are returned to the command line.
function varargout = imageRegistrationGUI_OutputFcn(hObject, eventdata, handles) 
% varargout  cell array for returning output args (see VARARGOUT);
% hObject    handle to figure
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

% Get default command line output from handles structure
varargout{1} = handles.output;


% --- Executes on button press in browseFixedImageBtn.
function browseFixedImageBtn_Callback(hObject, eventdata, handles)
% hObject    handle to browseFixedImageBtn (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

% Allow user to select fixed image file
[filename, pathname] = uigetfile({'*.tif;*.tiff;*.jpg;*.jpeg;*.bmp;*.png','All Image Files';...
    '*.*','All Files'}, 'Select Fixed Image File');
if isequal(filename,0) || isequal(pathname,0)
    return;
else
    handles.fixedImageFile = fullfile(pathname, filename);
    set(handles.fixedImageFilePath, 'String', handles.fixedImageFile);
end

% Update handles structure
guidata(hObject, handles);


function fixedImageFilePath_Callback(hObject, eventdata, handles)
% hObject    handle to fixedImageFilePath (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

% Hints: get(hObject,'String') returns contents of fixedImageFilePath as text
%        str2double(get(hObject,'String')) returns contents of fixedImageFilePath as a double


% --- Executes during object creation, after setting all properties.
function fixedImageFilePath_CreateFcn(hObject, eventdata, handles)
% hObject    handle to fixedImageFilePath (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    empty - handles not created until after all CreateFcns called

% Hint: edit controls usually have a white background on Windows.
%       See ISPC and COMPUTER.
if ispc && isequal(get(hObject,'BackgroundColor'), get(0,'defaultUicontrolBackgroundColor'))
    set(hObject,'BackgroundColor','white');
end


% --- Executes on button press in browseMovingImageBtn.
function browseMovingImageBtn_Callback(hObject, eventdata, handles)
% hObject    handle to browseMovingImageBtn (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

% Allow user to select moving image file
[filename, pathname] = uigetfile({'*.tif;*.tiff;*.jpg;*.jpeg;*.bmp;*.png','All Image Files';...
    '*.*','All Files'}, 'Select Moving Image File');
if isequal(filename,0) || isequal(pathname,0)
    return;
else
    handles.movingImageFile = fullfile(pathname, filename);
    set(handles.movingImageFilePath, 'String', handles.movingImageFile);
end

% Update handles structure
guidata(hObject, handles);


function movingImageFilePath_Callback(hObject, eventdata, handles)
% hObject    handle to movingImageFilePath (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

% Hints: get(hObject,'String') returns contents of movingImageFilePath as text
%        str2double(get(hObject,'String')) returns contents of movingImageFilePath as a double


% --- Executes during object creation, after setting all properties.
function movingImageFilePath_CreateFcn(hObject, eventdata, handles)
% hObject    handle to movingImageFilePath (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    empty - handles not created until after all CreateFcns called

% Hint: edit controls usually have a white background on Windows.
%       See ISPC and COMPUTER.
if ispc && isequal(get(hObject,'BackgroundColor'), get(0,'defaultUicontrolBackgroundColor'))
    set(hObject,'BackgroundColor','white');
end


% --- Executes on button press in selectControlPointsBtn.
function selectControlPointsBtn_Callback(hObject, eventdata, handles)
% hObject    handle to selectControlPointsBtn (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

% Read fixed image and moving image
fixedImage = imread(handles.fixedImageFile);
movingImage = imread(handles.movingImageFile);

% Display the two images
axes(handles.fixedImageAxes);
imshow(fixedImage);
title('Fixed Image');
axes(handles.movingImageAxes);
imshow(movingImage);
title('Moving Image');

% Allow user to manually select control points
[fixedPoints,movingPoints] = cpselect(fixedImage,movingImage,'Wait',true);

% Store control points in handles
handles.fixedPoints = fixedPoints;
handles.movingPoints = movingPoints;

% Update handles structure
guidata(hObject, handles);


% --- Executes on button press in registerImageBtn.
function registerImageBtn_Callback(hObject, eventdata, handles)
% hObject    handle to registerImageBtn (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

% Read fixed image and moving image
fixedImage = imread(handles.fixedImageFile);
movingImage = imread(handles.movingImageFile);

% Retrieve control points from handles
fixedPoints = handles.fixedPoints;
movingPoints = handles.movingPoints;

% Perform image registration using control points
tform = fitgeotrans(movingPoints, fixedPoints, 'affine');
registeredImage = imwarp(movingImage, tform, 'OutputView', imref2d(size(fixedImage)));

% Display the registered image
axes(handles.registeredImageAxes);
imshow(registeredImage);
title('Registered Image');

% Save the registered image
[filename, pathname] = uiputfile({'*.tif;*.tiff;*.jpg;*.jpeg;*.bmp;*.png','All Image Files';...
    '*.*','All Files'}, 'Save Registered Image As', 'registeredImage.tif');
if isequal(filename,0) || isequal(pathname,0)
    return;
else
    imwrite(registeredImage, fullfile(pathname, filename));
end


% --- Executes on button press in autoSelectControlPointsBtn.
function autoSelectControlPointsBtn_Callback(hObject, eventdata, handles)
% hObject    handle to autoSelectControlPointsBtn (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

% Read fixed image and moving image
fixedImage = imread(handles.fixedImageFile);
movingImage = imread(handles.movingImageFile);

% Detect Harris corners in fixed image and moving image
fixedPoints = detectHarrisFeatures(fixedImage);
movingPoints = detectHarrisFeatures(movingImage);

% Extract features in the fixed image and moving image
[fixedFeatures, fixedPoints] = extractFeatures(fixedImage, fixedPoints);
[movingFeatures, movingPoints] = extractFeatures(movingImage, movingPoints);

% Match features between the fixed image and moving image
indexPairs = matchFeatures(fixedFeatures, movingFeatures);

% Retrieve matched points in the fixed image and moving image
fixedPoints = fixedPoints(indexPairs(:,1),:);
movingPoints = movingPoints(indexPairs(:,2),:);

% Store control points in handles
handles.fixedPoints = fixedPoints.Location;
handles.movingPoints = movingPoints.Location;

% Update handles structure
guidata(hObject, handles);

% Display the two images and the matched points
axes(handles.fixedImageAxes);
imshow(fixedImage);
hold on;
plot(fixedPoints);
title('Fixed Image with Control Points');
axes(handles.movingImageAxes);
imshow(movingImage);
hold on;
plot(movingPoints);
title('Moving Image with Control Points');


% --- Executes on button press in clearControlPointsBtn.
function clearControlPointsBtn_Callback(hObject, eventdata, handles)
% hObject    handle to clearControlPointsBtn (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

% Clear control points from handles
handles = rmfield(handles, 'fixedPoints');
handles = rmfield(handles, 'movingPoints');

% Clear control point displays
axes(handles.fixedImageAxes);
cla;
title('');
axes(handles.movingImageAxes);
cla;
title('');

% Update handles structure
guidata(hObject, handles);

以上是基于图形界面的MATLAB遥感图像配准程序，其中包含了参考影像、待配准影像文件读取，控制点存储，配准后的影像写入等功能。此外，该程序还包含了基于人工选取控制点和基于Harris角点自动提取控制点两种配准方法。完整的代码可以在MATLAB中创建GUI后，在GUIDE中编辑生成。