% --- Executes on button press in pushbutton1.
function pushbutton1_Callback(hObject, eventdata, handles)
% hObject    handle to pushbutton1 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)
% “选择文件夹”按钮的回调函数，弹出文件夹打开对话框，选择待拼接图片

% 初始化四个坐标轴属性，清空图片，恢复到系统初始化状态
axes(handles.axes1); cla reset; box on; set(gca, 'XTickLabel', [], 'YTickLabel', []);
axes(handles.axes2); cla reset; box on; set(gca, 'XTickLabel', [], 'YTickLabel', []);
axes(handles.axes3); cla reset; box on; set(gca, 'XTickLabel', [], 'YTickLabel', []);
axes(handles.axes4); cla reset; box on; set(gca, 'XTickLabel', [], 'YTickLabel', []);

% 清空axes1,axes2，上一次拼接的结果以及拼接完的图片
handles.file = [];
handles.MStitch = [];
handles.grayResult = [];
handles.RGBResult = [];
 
dname = uigetdir('.\\images', '请选择待拼接图像文件夹：');
% folder_name =uigetdir(start_path,dialog_title) 
% start_path为默认的路径，dialog_title为对话框名称，returns the directory name as a string. 

if dname == 0          %异常处理
    return;
end
df = ls(dname);
if length(df) > 2
    for i = 1 : size(df, 1)
        if strfind(df(i, :), '.db');
            df(i, :) = [];
            break;
        end
    end
    if length(df) > 2
        filename = fullfile(dname, df(end, :));
        pathname = [dname '\'];
    else
        msgbox('请选择至少两幅图像！', '提示信息', 'warn');
        return;
    end
else
    msgbox('请选择至少两幅图像！', '提示信息', 'warn');
    return;
end
%图片序列处理
file = File_Process(filename, pathname);
if length(file) < 2
    msgbox('请选择至少两幅图像！', '提示信息', 'warn');
    return;
end
Img1 = imread(file{1}); 
Img2 = ImageList(file); 
axes(handles.axes1);
imshow(Img1); title('图像序列1');
axes(handles.axes2);
imshow(Img2); title('图像序列2');

handles.Img1 = Img1;
handles.Img2 = Img2;
handles.file = file;
guidata(hObject, handles);

效果图如下：

二、图像匹配功能

当用户点击“图像匹配”按钮时，软件会先判断 handles.file 是否为空，若为空，证明用户未进行待拼接图像导入步骤，msgbox 会提示“请先载入图像！”。

代码如下：

function pushbutton7_Callback(hObject, eventdata, handles)
% hObject    handle to pushbutton7 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)
% “图像匹配”按钮的回调函数，完成图像匹配，显示信息对话框。

if isempty(handles.file)
    msgbox('请先载入图像！', '提示信息', 'modal');
    return;
end
if ~isempty(handles.MStitch)
    msgbox('图像匹配已完成！', '提示信息', 'modal');
    return;
end

file = handles.file;
im1 = imread(file{1});
MStitch.imrgb1 = double(im1); 
im1 = rgb2gray(im1);
MStitch.im1 = double(im1); 
[Pheight, Pwidth] = size(im1);
MStitch.Pwidth = Pwidth; 
MStitch.Pheight = Pheight; 
MStitch.W_min = round(0.60*Pwidth);
MStitch.W_max = round(0.83*Pwidth); 
MStitch.H_min = round(0.98*Pheight); 
MStitch.minval = 255;
im2 = imread(file{2});
MStitch.imrgb2 = double(im2);
im2 = rgb2gray(im2);
im2 = double(im2);
MStitch.im2 = double(im2);
[W_box, H_box, bdown, MStitch] = Fun_Match(im2, MStitch);
msgbox('图像匹配完成！', '提示信息', 'modal');
handles.W_box = W_box;
handles.H_box = H_box;
handles.bdown = bdown;
handles.MStitch = MStitch;
guidata(hObject, handles);

% --- Executes on button press in pushbutton2.
function pushbutton2_Callback(hObject, eventdata, handles)
% hObject    handle to pushbutton2 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

if isempty(handles.file)
    msgbox('请先载入图像！', '提示信息', 'modal');
    return;
end
if isempty(handles.MStitch)
    msgbox('请先进行图像匹配！', '提示信息', 'modal');
    return;
end
if ~isempty(handles.grayResult)
    msgbox('灰度拼接图像已完成！', '提示信息', 'modal');
    return;
end
if length(handles.file)
    [MStitch, result] = GrayMain_Process(handles.MStitch, ...
        handles.W_box, handles.H_box, handles.bdown);
end
grayResult = im2uint8(mat2gray(result));
axes(handles.axes3); cla reset; box on; set(gca, 'XTickLabel', [], 'YTickLabel', []);
imshow(grayResult, []);
title('灰度图像拼接结果');

handles.grayResult = grayResult;
guidata(hObject, handles);

msgbox('灰度拼接图像完成！', '提示信息', 'modal');

% --- Executes on button press in pushbutton4.
function pushbutton4_Callback(hObject, eventdata, handles)
% hObject    handle to pushbutton4 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)
% “显示拼接图像”按钮的回调函数，弹出信息提示对话框，显示已拼接图像

if isempty(handles.RGBResult)
    msgbox('没有进行图像拼接！请先进行图像拼接。', '提示信息', 'error');
    return;
end

if ~isempty(handles.RGBResult)
    figure(1);imshow(handles.RGBResult, []);
    title('图像拼接结果');
end

if ~isempty(handles.RGBListResult)
    figure(2); imshow(handles.RGBListResult, []);
    title('序列图像拼接结果');
end

% --- Executes on button press in pushbutton6.
function pushbutton6_Callback(hObject, eventdata, handles)
% hObject    handle to pushbutton6 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)
% “保存拼接图像”按钮的回调函数，弹出信息提示对话框，保存已拼接图像

if isempty(handles.RGBResult)
    msgbox('没有进行图像拼接！请先进行图像拼接！', '提示信息', 'error');
    return;
end
[filename, pathname] = uiputfile({'*.jpg;*.tif;*.png;*.gif','All Image Files';...
    '*.*','All Files' }, '保存拼接结果图像', ...
    'Result\result.jpg');
if isequal(filename, 0)
    return;
end
[pathstr, name, ext] = fileparts(filename);

if ~isempty(handles.RGBResult)
    file = fullfile(pathname, [name, ext]);
    imwrite(handles.RGBResult, file);
end

if ~isempty(handles.RGBListResult)
    file = fullfile(pathname, [name, '_List', ext]);
    imwrite(handles.RGBListResult, file);
end

msgbox('保存拼接图像成功！', '提示信息', 'modal');

% --- Executes on button press in pushbutton8.
function pushbutton8_Callback(hObject, eventdata, handles)
% hObject    handle to pushbutton8 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)
% “退出系统”按钮的回调函数，弹出问题提示对话框，选择是否退出系统

choice = questdlg('您确定要退出无人机航拍图像拼接系统？', ...
    '退出选项', ...
    '退出', '取消', '取消');
switch choice
    case '退出'
        close all;
    case '取消'
        return;
end