intrinsicsParams = helperReadYAML('cameraParams.yaml');

imageSize = [intrinsicsParams.image_height intrinsicsParams.image_width]; intrinsicMatrix = intrinsicsParams.camera_matrix; distortionCoefficients = intrinsicsParams.distortion_coefficients; intrinsicsObj = cameraIntrinsicsFromOpenCV(intrinsicMatrix,distortionCoefficients,imageSize);

% Load the captured image.imageName = fullfile(toolboxdir('vision'),'visiondata','calibration','stereo','left','left01.png'); I = imread(imageName);% Undistort the image.J = undistortImage(I,intrinsicsObj,'OutputView','full');% Display the result.figure montage({I,J})

functioncameraParams = helperReadYAML(filename)% helperReadYAML reads a ROS YAML file, filename, and returns a structure% with these fields: image_width, image_height, camera_name,% camera_matrix, distortion_model, distortion_coefficients,% rectification_matrix, and projection_matrix. These fields are stored% in the YAML file colon separated from their values in different lines.f = fopen(filename,'r'); stringFields = {'camera_name','distortion_model'};while~feof(f) [name,value,isEmptyLine] = helperReadYAMLLine(f);ifisEmptyLinecontinueendif~isempty(value)% Convert all values to numbers except for known string% fields.if~any(contains(name, stringFields)) value = str2num(value);%#okendelse% An empty value in ROS YAML files indicates a matrix in% upcoming lines. Read the matrix from the upcoming lines.value = helperReadYAMLMatrix(f);end% Store post-processed value.cameraParams.(name) = value;endfclose(f);end

functionmatrix = helperReadYAMLMatrix(f)% helperReadYAMLMatrix reads a matrix from the ROS YAML file. A matrix in% a ROS YAML file has three fields: rows, columns and data. rows and col% describe the matrix size. data is a continguous array of the matrix% elements in row-major order. This helper function assumes the presence% of all three fields of a matrix to return the correct matrix.numRows = 0; numCols = 0; data = [];% Read numRows, numCols and matrix data.while~feof(f) [name,value,isEmptyLine] = helperReadYAMLLine(f);ifisEmptyLinecontinueendswitchnamecase'rows'numRows = str2num(value);%#okcase'cols'numCols = str2num(value);%#okcase'data'data = str2num(value);%#ok% Terminate the while loop as data is the last% field of a matrix in the ROS YAML file.breakotherwise% Terminate the while loop if any other field is% encountered.breakendendifnumel(data) == numRows*numCols% Reshape the matrix using row-major order.matrix = reshape(data,[numCols numRows])';endend

function[name,value,isEmptyLine] = helperReadYAMLLine(f)% Read line from file.line = fgetl(f);% Trim leading and trailing whitespaces.line = strtrim(line);ifisempty(line) || line(1)=='//www.tatmou.com/kr/kr/help/vision/ref/#'% Empty line or comment.name =''; value =''; isEmptyLine = true;else% Split the line to get name and value.c = strsplit(line,':'); assert(length(c)==2,'Unexpected file format') name = c{1}; value = strtrim(c{2});% Trim leading whitespace.isEmptyLine = false;endend