Stereo Vision on Matlab (Rectification error)

Question

I am working on Stereo vision task and trying to run this algorithm:

numImagePairs = 11;
imageFiles1 = cell(1,numImagePairs);
imageFiles2 = cell(1,numImagePairs);
imagemDir = fullfile('C:','Users','carlo','Documents','Iniciacao','Matlab','Principal');

for i = 1:numImagePairs
imageFiles1{i} = fullfile(imagemDir, sprintf('left%02d.jpg',i));
imageFiles2{i} = fullfile(imagemDir, sprintf('right%02d.jpg',i));
end

%Detect the checkerboard
[imagePoints,boardSize,pairsUsed] = detectCheckerboardPoints(imageFiles1,imageFiles2);

%Generate world coordinates of the checkerboard points
squareSize=29; %millimeters
worldPoints= generateCheckerboardPoints(boardSize, squareSize);

%Compute the stereo camera parameters
stereoParams= estimateCameraParameters(imagePoints,worldPoints);


%Evaluate calibration accuracy
figure;
showReprojectionErrors(stereoParams);

%Read in the stereo pair of images
I1 = imread('left.jpg');
I2 = imread('right.jpg');

%Rectify the images
[J1,J2]=rectifyStereoImages(I1,I2,stereoParams);

%Display the images before rectification
figure;
imshow(stereoAnaglyph(I1,I2));
title('Before rectification');

%Display the images after rectification
figure;
imshow(stereoAnaglyph(J1,J2));
title('After rectification');


%Generate the disparity map
disparityMap = disparity(J1,J2);
figure;
imshow(disparityMap, [0,64]);
colormap('jet');
colorbar;
title('Disparity Map');

EDIT

Running this leads to the output:

Operands to the || and && operators must be convertible to logical scalar values.

Error in vision.internal.calibration.CameraParametersImpl/getValidBounds (line 883)
        if isempty(coder.target) && (left > right || top > bot)

Error in vision.internal.calibration.CameraParametersImpl/computeUndistortBounds (line 785)
                [xBounds, yBounds] = getValidBounds(this, undistortedMask, ...

Error in vision.internal.calibration.StereoParametersImpl/computeOutputBounds (line 371)
        [xBoundsUndistort1, yBoundsUndistort1] = ...

Error in vision.internal.calibration.StereoParametersImpl/computeRectificationParameters (line 271)
        [xBounds, yBounds] = computeOutputBounds(this, imageSize, ...

Error in vision.internal.calibration.StereoParametersImpl/rectifyStereoImagesImpl (line 190)
            [H1, H2, Q, xBounds, yBounds] = ...

Error in rectifyStereoImages (line 99)
[rectifiedImage1, rectifiedImage2] = rectifyStereoImagesImpl(stereoParams, ...

Error in new_project (line 55)
[J1, J2] = rectifyStereoImages(I1, I2, stereoParams);

In this case all the corners of all images were detected, which means that the calibration apparently is running ok and are 11 centimeters of distance between the two cameras.

Dima Dima · Accepted Answer · 2015-08-24T14:05:33

This error indicates that rectifyStereoImages cannot compute the bounds of the output image. This usually means that you need more calibration images to get a better estimate of the distortion coefficients. You want to make sure that you get points close to edges and corners of your field of view.

First, try the following:

[J1,J2]=rectifyStereoImages(I1,I2,stereoParams, 'OutputView', 'full');

Also, it would be very helpful if you could post a few of your calibration images.

Stereo Vision on Matlab (Rectification error)

1 Answers