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Save Camera Calibration Parameters

Erin 님이 질문을 제출함. 13 Mar 2014
The export of camera parameters from the Camera Calibration toolbox creates its own type of variable that cannot be saved as a .mat. How can I save these so that I can load it when I want to use that camera instead of calibrating it every time? Is xml the only way?
Thanks, Erin

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It's a 1x1 vision.CameraParameters object
There is a command toStruct(cameraParams) which seems to work,so if you have created a cameraParameters object in your workspace
mycamParams = toStruct(cameraParams)
save mycamParams.mat mycamParams %Saves as a mat file
clear %clear variables in workspace
load('mycamParams.mat') %loads it back in and Matlab recognises it is a structure
mycamParams=cameraParameters(parameterStruct) % recreates the camera parameters object which you can then use to undistort images etc.
I have an image how can I find camera calibration for that.

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Dima Lisin 님의 답변 1 May 2014
Dima Lisin 님이 편집함. 1 May 2014
 채택된 답변

You certainly can save the camera parameters object into a mat file, just like any other variable. Export the variable to workspace. Let's call it myParams. Then do
>> save myParams.mat myParams
That should work.

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I kept getting an error: ""Argument must contain a character vector". I slightly modified Dima's suggestion to make it work for me:
>> save 'myParams' myParams
Matt J 12 Dec 2018
Hard to see why the modification was necessary or made any difference. Maybe you were originally using the functional form of save as follows,
save('myParams',myParams)

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Sean de Wolski 님의 답변 13 Mar 2014

With MATLAB R2014a, you can generate equivalent code with the app.

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I unfortunately have 2013b not 2014a.
You can probably get a free upgrade if you purchased R2013b.
It's a company license so I can't.
Basically I am trying to save the object of the type vision.CameraParameters class. I would like to be able to save it out of my workspace so that I can just reload it to use it for undistortImage instead of rerunning the calibration each time my workspace gets cleared.

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Matt J 님의 답변 13 Mar 2014
Matt J 님이 편집함. 13 Mar 2014

You could write a customized save routine that exports the CameraParameters properties and saves them in a structure
function save_cameraParams(cpObject,fileName)
fields={'IntrinsicMatrix', 'RadialDistortion',etc...}
for ii=1:length(fields)
S.(fields{ii})=cpObject.(fields{ii});
end
save(fileName, 'S');
end
Then a similar one to reload and rebuild the vision.CameraParameters object,
function cpObject=load_cameraParams(fileName)
S=load(fileName); S=S.S
pairs=[fieldnames(S), struct2cell(S)].';
cpObject=vision.CameraParameters(pairs{:});
end

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