首先，看一下图像中的宽高与笛卡尔坐标系之间的关系如下图所示，即x与width(cols)对应，y与height(rows)对应，x是按列来进行变化，y按行变化。



OpenCV读入图像以Mat形式存储时，为Mat（Width，Height），访问时用的是A=Mat.at（y,x），y代表行，x代表列；

MATLAB读入图像以Mat形式存储时，为Mat（Height，Width），访问时用B=Mat(y,x),同OpenCV，由于存储时互为转置关系，因此访问同一幅图片中同一个像素，MATLAB里面的Mat(i,j)对应的OpenCV里面为Mat(j,i)。对比如图2



对于opencv的Rect(int x,int y,int width,int height)结构而言，x代表起始点的列坐标(即cols)，y代表起始点的行坐标(即rows)。

图像的批量存储
savepath='F:\matlabwork\Target image\blank1';
for i=0:10
    x=b+2.5*d+i*7*d; 
    rect=[a+(7*i-4)*d,m-1.5*d,3*d,3*d];
    A=imcrop(im,rect);
  imwrite(A,[savepath,num2str(i'%02d'),'.bmp']);%将处理后的图片保存在F:\matlabwork\Target image\下，命名为01.bmp
end;

图片的批量读写`
str='F:\matlabwork\Target image\blank1-'; %我的图像放在F盘，matlabwork\Target image\图像文件夹下,图片的前缀是blank1-；
for i=1:20
    I=imread([str,num2str(i),'.bmp']); %依次读取每一幅图像
end

读取指定目录下的图片
Img1=imread('F:\matlabwork\blank\blank81.bmp'); %读取指定文件下的图片

使用matlab显示.mat文件的图像（ground truth）

将数组或者矩阵保存为一个mat格式的文件，进行load命令读取a=load('gth.mat')；

当进行imshow（a,[]）;显示图像时

发生报错：

Error using imageDisplayValidateParams

Expected input number 1, I, to be one of these types:


  double, single, uint8, uint16, uint32, uint64, int8, int16, int32, int64, logical


Instead its type was struct.


Error in imageDisplayValidateParams (line 12)

validateattributes(common_args.CData, {'numeric','logical'},...


Error in imageDisplayParseInputs (line 79)

common_args = imageDisplayValidateParams(common_args);


Error in imshow (line 198)

  [common_args,specific_args] = ...


报错原因：得到的a是struct类型的数据，而imshow（）显示应该是一个矩阵或者数组。


如何修改：将命令改写为：a=cell2mat(struct2cell(load('gth.mat')));得到的a即为矩阵。imshow（a,[]）;可正常显示。

一、简介
本GUI实现的功能：加载图片、灰度处理图片、0.5倍缩放图片、保存处理

版本为R2014a中文版本
二、源代码
function varargout = GUI_TEST(varargin)
% GUI_TEST MATLAB code for GUI_TEST.fig
%      GUI_TEST, by itself, creates a new GUI_TEST or raises the existing
%      singleton*.
%
%      H = GUI_TEST returns the handle to a new GUI_TEST or the handle to
%      the existing singleton*.
%
%      GUI_TEST('CALLBACK',hObject,eventData,handles,...) calls the local
%      function named CALLBACK in GUI_TEST.M with the given input arguments.
%
%      GUI_TEST('Property','Value',...) creates a new GUI_TEST or raises the
%      existing singleton*.  Starting from the left, property value pairs are
%      applied to the GUI before GUI_TEST_OpeningFcn gets called.  An
%      unrecognized property name or invalid value makes property application
%      stop.  All inputs are passed to GUI_TEST_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 GUI_TEST

% Last Modified by GUIDE v2.5 20-Mar-2020 09:03:44

% Begin initialization code - DO NOT EDIT
gui_Singleton = 1;
gui_State = struct('gui_Name',       mfilename, ...
                   'gui_Singleton',  gui_Singleton, ...
                   'gui_OpeningFcn', @GUI_TEST_OpeningFcn, ...
                   'gui_OutputFcn',  @GUI_TEST_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 GUI_TEST is made visible.
function GUI_TEST_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 GUI_TEST (see VARARGIN)

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

% Update handles structure
guidata(hObject, handles);

% UIWAIT makes GUI_TEST wait for user response (see UIRESUME)
% uiwait(handles.figure1);
global label;
label=0;



% --- Outputs from this function are returned to the command line.
function varargout = GUI_TEST_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 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)
global OriginalPic;

[filename,pathname]=uigetfile({'*.bmp;*.jpg;*.png;*.jpeg;*.tif'},'选择一个图片','F:\test');
str=[pathname filename];

if isequal(filename,0)||isequal(pathname,0)
    warndlg('Please select a picture first!','Warning');
    return;
else
    OriginalPic= imread(str);
    axes(handles.axes1);
    imshow(OriginalPic);
end;





% --- Executes on button press in pushbutton5.
function pushbutton5_Callback(hObject, eventdata, handles)
% hObject    handle to pushbutton5 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)
global OriginalPic;
global GrayPic;
global label;

[rows , cols , colors] = size(OriginalPic); %原图的矩阵参数
GrayPic = zeros(rows , cols);  %用参数创建一个全零矩阵，来存储用灰度图像
GrayPic = uint8(GrayPic);%图像是double型的，将全零矩阵转化为uint8格式
for i = 1:rows  
    for j = 1:cols  
        GrayPic(i , j) = OriginalPic(i , j , 1)*0.3+OriginalPic(i , j , 2)*0.59+OriginalPic(i , j , 3)*0.11; 
        %按照W=0.30,V=0.59,U=0.11进行加权运算，得到最合理的灰度图像
    end  
end  

axes(handles.axes2);
imshow(GrayPic);
label=1;




% --- 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)
global OriginalPic;
global ScalePic;
global label;

ScalePic=imresize(OriginalPic,0.5,'cubic');

axes(handles.axes2);
imshow(ScalePic);
label=2;


% --- Executes on button press in pushbutton7.
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)
global OriginalPic;
global GrayPic;
global ScalePic;
global label;

[FileName,PathName] = uiputfile({'*.jpg','JPEG(*.jpg)';...
                                 '*.bmp','Bitmap(*.bmp)';...
                                 '*.gif','GIF(*.gif)';...
                                 '*.*',  'All Files (*.*)'},...
                                 'Save Picture','Untitled');

三、运行结果



四、备注
完整代码或者代写添加QQ 1564658423