adjust axes as the loaded image size.

I want to load different size of images on axes. I want to know that When image is loaded, how the size of axes is adjusted as the size of loaded image.

Answer 1

[Image Analyst]

It does its best to adjust the size of the displayed image given the initial size of the axes and the size and aspect ratio of the image being displayed. I don't know the exact algorithm. If you want fixed axes sizes, and fixed magnification then you can set up those with calls to set() and imshow() respectively.

[Nan]

Thanks for your answer. To use set() function, I think I initially have to get the dimension of the input image. Although I can get the size of image by using s.bytes, I don't know how can I get the dimension of image and how to set these dimension on the axes sizes. Please give some advices.

[Image Analyst]

See my demo:

% Demo to display an image with random size and location.
% By ImageAnalyst
clc;    % Clear the command window.
close all;  % Close all figures (except those of imtool.)
imtool close all;  % Close all imtool figures.
clear;  % Erase all existing variables.
workspace;  % Make sure the workspace panel is showing.
fontSize = 14;

% Read in a standard MATLAB gray scale demo image.
folder = fullfile(matlabroot, '\toolbox\images\imdemos');
baseFileName = 'cameraman.tif';
% Get the full filename, with path prepended.
fullFileName = fullfile(folder, baseFileName);
if ~exist(fullFileName, 'file')
  % Didn't find it there.  Check the search path for it.
  fullFileName = baseFileName; % No path this time.
  if ~exist(fullFileName, 'file')
    % Still didn't find it.  Alert user.
    errorMessage = sprintf('Error: %s does not exist.', fullFileName);
    uiwait(warndlg(errorMessage));
    return;
  end
end
grayImage = imread(fullFileName);
% Get the dimensions of the image.  numberOfColorBands should be = 1.
[rows columns numberOfColorBands] = size(grayImage);
% Display the original gray scale image.
imshow(grayImage, []);
title('Grayscale Image', 'FontSize', fontSize);
% Enlarge figure to full screen.
set(gcf, 'units','normalized','outerposition',[0 0 1 1]);
set(gcf,'name','Demo To display image in random location and random sizes','numbertitle','off') 
axis on;

keepGoing = true;  % Keep going until user cancels out.
maxRuns = 30; % Fail safe to prevent going on forever.
thisRun = 1;
while keepGoing && thisRun < maxRuns
  % Make it a random size:
  randomWidth = max(0.1, rand(1));
  randomHeight = max(0.1, rand(1));
  % Make it show at a rnadom location.
  % Make it fit on screen.
  randomX = (1 - randomWidth) * rand(1);
  randomY = (1 - randomHeight) * rand(1);
  myRect = [randomX, randomY, randomWidth, randomHeight];
  
  % Do the sizong and positioning.
  set(gca, 'units','normalized', 'outerposition', myRect);
  
  % Notify user and allow opportunity to exit.
  locationMessage = sprintf('X = %.4f\nY = %.4f\nWidth = %.4f\nHeight = %.4f\n', myRect);    
  promptMessage = sprintf('%s\n\nDo you want to display another random size at another random location?', locationMessage);
  button = questdlg(promptMessage, 'Continue?', 'Continue', 'Cancel', 'Continue');
  if strcmp(button, 'Cancel')
    keepGoing = false;
    break;
  end
  thisRun = thisRun + 1;  % Increment failsafe.
end