You can get information about the image file using imfinfo, which displays a structure with various fields, including width, height, and colort type.
For instance:
InfoImage = imfinfo('peppers.png');
InfoImage =
Filename: '/Applications/MATLAB_R2014a.app/toolbox/matlab/imagesc...'
FileModDate: '02-Apr-2013 15:55:52'
FileSize: 287677
Format: 'png'
FormatVersion: []
Width: 512
Height: 384
BitDepth: 24
ColorType: 'truecolor'
FormatSignature: [137 80 78 71 13 10 26 10]
Colormap: []
Histogram: []
InterlaceType: 'none'
Transparency: 'none'
SimpleTransparencyData: []
BackgroundColor: []
RenderingIntent: []
Chromaticities: []
Gamma: []
XResolution: []
YResolution: []
ResolutionUnit: []
XOffset: []
YOffset: []
OffsetUnit: []
SignificantBits: []
ImageModTime: '16 Jul 2002 16:46:41 +0000'
Title: []
Author: []
Description: 'Zesty peppers'
Copyright: 'Copyright The MathWorks, Inc.'
CreationTime: []
Software: []
Disclaimer: []
Warning: []
Source: []
Comment: []
OtherText: []
Then you can get the information you need with a regular structure assignment:
With = InfoImage.Width;
Height = InfoImage.Height;
Colortype = InfoImage.ColorType;
After that you are good to go. You can display this information in text fields by setting the String property for them:
set(handles.WidthTextbox,'String',num2str(InfoImage.Width));
and so on for the other fields.
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