get canvas imageData after reading the file using ITK.js

Hi, I am using ITK.js to read input DICOM slices. The main reason why I am using ITK is `itkImage` contains some useful information of slice for my next visualizing steps, such as **origin**, **spacing**, etc., instead of using other JavaScript libaries to get these tags, so it's kind of time-consuming. Is it possible to convert `itkImage` to original canvas `imageData` after taking all the necessary tags into an array? Since I need the original `imageData` for my next steps.