www.gusucode.com > images 案例代码 matlab源码程序 > images/WriteImageDataToFileInGraphicsFormatExample.m

    %% Write Image Data to File in Graphics Format
% This example shows how to write image data from the MATLAB workspace to a
% file in one of the supported graphics file formats using the |imwrite|
% function. 
%%
% Load image data into the workspace. This example loads the indexed image
% |X| from a MAT-file, |clown.mat|, along with the associated colormap
% |map|.

% Copyright 2015 The MathWorks, Inc.

load clown
whos
%%
% Export the image data as a bitmap file using |imwrite|, specifying the
% name of the variable and the name of the output file you want to create.
% If you include an extension in the filename, |imwrite| attempts to infer
% the desired file format from it. For example, the file extension |.bmp|
% specifies the Microsoft Windows Bitmap format.  You can also specify the
% format explicitly as an argument to |imwrite|.
imwrite(X,map,'clown.bmp')
%%
% Use format-specific parameters with |imwrite| to control aspects of the
% export process. For example, with PNG files, you can specify
% the bit depth. To illustrate, read an image into the workspace in TIFF
% format and note its bit depth.
I = imread('cameraman.tif');
s = imfinfo('cameraman.tif');
s.BitDepth
%%
% Write the image to a graphics file in PNG format, specifying a bit depth
% of 4.
imwrite(I,'cameraman.png','Bitdepth',4)
%%
% Check the bit depth of the newly created file.
newfile = imfinfo('cameraman.png');
newfile.BitDepth