plot3d of jpeg file contains a triangle(2D) and data of triangle in z-axis

I have a jpeg file contains a triangle in a rectangle and a set of data corresponding to the points of that triangle. How to plot3d of that jpeg on xy plane and data in z-axis?

[Merged from duplicate]

I have a jpeg file contains a triangle in a rectangle and a set of data corresponding to the points of that triangle. How to plot3d of that jpeg on xy plane and data in z-axis? I tried surf() which plot y-axis as z

[Walter Roberson]

Do you mean that the jpeg file has some text in it that you need to do optical recognition of in order to do the plot?

http://www.mathworks.com/matlabcentral/answers/7924-where-can-i-upload-images-and-files-for-use-on-matlab-answers

[Walter Roberson]

surf() does not plot the y axis as z.

Answer 1

[Image Analyst]

Have you tried the surf() function? If it's a color image, then you can only plot one of the color channels as a height. You'd need 3 surfaces to plot the three different color channels each as a surface, like in this demo:

clc;    % Clear the command window.
close all;  % Close all figures (except those of imtool.)
imtool close all;  % Close all imtool figures if you have the Image Processing Toolbox.
clear;  % Erase all existing variables. Or clearvars if you want.
workspace;  % Make sure the workspace panel is showing.
format long g;
format compact;
fontSize = 20;

% Read in a standard MATLAB color demo image.
folder = fullfile(matlabroot, '\toolbox\images\imdemos');
baseFileName = 'onion.png';
% 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
rgbImage = imread(fullFileName);
% Get the dimensions of the image.  numberOfColorBands should be = 3.
[rows columns numberOfColorBands] = size(rgbImage);
% Display the original color image.
subplot(2, 2, 1);
imshow(rgbImage);
title('Original Color Image', 'FontSize', fontSize);
% Enlarge figure to full screen.
set(gcf, 'units','normalized','outerposition',[0 0 1 1]);

% Extract the individual red, green, and blue color channels.
redChannel = rgbImage(:, :, 1);
greenChannel = rgbImage(:, :, 2);
blueChannel = rgbImage(:, :, 3);

% Plot each color channel as a surface:
subplot(2,2,2);
surf(double(redChannel));
title('Red Channel', 'FontSize', fontSize);
subplot(2,2,3);
surf(double(greenChannel));
title('Green Channel', 'FontSize', fontSize);
subplot(2,2,4);
surf(double(blueChannel));
title('Blue Channel', 'FontSize', fontSize);