MATLAB: RectifyStereoImages doesn’t cope with projective2d transforms being passed to it for uncalibrated stereo pairs

Computer Vision Toolboxrectifystereoimages

When following the code example at http://au.mathworks.com/help/vision/examples/uncalibrated-stereo-image-rectification.html I get an error no the final image rectification step with the following command (output included) I wonder if my version of the Computer Vision Toolbox (6.1 under R2014b) is not supporting this operation?:

>> [I1Rect, I2Rect] = rectifyStereoImages(I1, I2, tform1, tform2); Error using rectifyStereoImages Expected stereoParams to be one of these types:

stereoParameters

Instead its type was projective2d.

Error in rectifyStereoImages>validateStereoParameters (line 129) validateattributes(params, {'stereoParameters'}, …

Error in rectifyStereoImages>parseInputs (line 109) validateStereoParameters(stereoParams);

Error in rectifyStereoImages (line 96) [I1, I2, interp, outputView, fillValues] = parseInputs(…

Thank you in advance of any advice received.

James

Best Answer

The current online documentation is for R2015b. The analogous documentation for R2014b is here Uncalibrated Stereo Image Rectification.

(I don’t have any version of the Toolbox, so the is the limit of my ability to help.)

Related Solutions

MATLAB: I calibrated the camera using Camera Calibration app,How do i apply it to the camera for further use

If you click the "Export" button on the app, it will export a cameraParameters object to your workspace. There is a variety of functions that use it, such as undistortImage, cameraMatrix, and cameraPose.

MATLAB: How to generate code for ‘rectifyStereoImages’ functionality to rectify stereo camera images

MATLAB coder does not support the passing of the 'stereoParameters' object as an argument into a function. I recommend you pass the information in as a struct, and then create the 'stereoParameters' object inside the function, as suggested in the link below:

https://www.mathworks.com/help/vision/ref/rectifystereoimages.html#bvmuj0w-1

The workflow is to:

1) Set up a function that accepts structs as an argument, and generates the 'stereoParams' within.

2) You can then pass this generated 'stereoParams' into the rectifyStereoImages function.

3) I also recommend setting up the 'stereoParams' to be a persistent variable, so it is not generated with each instance of the function being called:

https://www.mathworks.com/help/matlab/ref/persistent.html

Thus , please create the following function:

% Input Arguments would be image matrices and a struct
function [a,b]= img_rec(img1,img2,stereoParamStruct)
    persistent stereoParams
    if isempty(stereoParams)
        % Create the stereoParams object using the input struct
        stereoParams = stereoParameters(stereoParamStruct);
    end
      % Now that the object is created, you can run 'rectifyStereoImages'
          [a,b]=rectifyStereoImages(img1, img2, stereoParams);
  end

You can use the commands listed below at the MATLAB command prompt to generate embeddable code.

>> params_str = toStruct(stereoParameters)
>> codegen img_rec -args {coder.typeof(img1), coder.typeof(img2), coder.typeof(params_str)};

Best Answer

Related Solutions

MATLAB: I calibrated the camera using Camera Calibration app,How do i apply it to the camera for further use

MATLAB: How to generate code for ‘rectifyStereoImages’ functionality to rectify stereo camera images

Related Question