get canvas imageData after reading the file using ITK.js

InsightSoftwareConsortium / ITK-Wasm

High performance spatial analysis in a web browser and across programming languages and hardware architectures

https://wasm.itk.org

Apache License 2.0

195 stars 48 forks source link

get canvas imageData after reading the file using ITK.js #240

Open truongleit opened 5 years ago

truongleit commented 5 years ago

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.

thewtex commented 5 years ago

It is possible to convert to a canvas imageData by using itkImage.data, with caveats:

Many / most DICOM image data is not UInt8, so rescaling will be necessary.
Many / most DICOM image data is not RGBA but scalar data, so duplicating components for grayscale images will be necessary.
Images with anisotropic spacing or non-identity direction will not render correctly.
Many DICOM are 3D, not 2D, so extraction of the desired slice is necessary.

So, it helps to use vtk.js, for example, for rendering to help with these issues.