Notebook sequence of views uses only first view ROI

[tbirdso]

Summary

When attempting to view multiple images in separate cells in a Jupyter Notebook with itkwidgets.view, only the first region of interest for the first cell run is used in subsequent displays. Trying to view a larger image after viewing a smaller image will display the entirety of the expected bounds.

The viewer otherwise behaves as normal without warnings or error messages, which makes it seem visibly as if the entirety of the image contains less information than expected. This can critically impact quantitative pipeline evaluation.

Minimal Reproducible Example

import numpy as np
from itkwidgets import view
import itk

# Create a smaller and larger image with unit spacing
arr = np.zeros([364, 210], dtype=np.float32)
arr[:,:105] = 1

arr2 = np.zeros([1292,500], dtype=np.float32)
arr2[:646,:] = 1

image = itk.image_from_array(arr) # physical bounds are (0,0), (210,364)
image2 = itk.image_from_array(arr2) # physical bounds are (0,0), (500, 1292)

# View smaller image first in a dedicated cell
view(image)

# View larger image second in a dedicated cell
view(image2)

Size values are based on issue occurrence when viewing ITKMontage tile data input vs output:

https://github.com/InsightSoftwareConsortium/ITKMontage/tree/master/examples/SampleData_CMUrun2

https://github.com/InsightSoftwareConsortium/ITKMontage/blob/master/examples/SimpleMontage.py

Expected Result

The full extent of both images are visible in respective notebook cells.

image2 (expected):

Observed Result

image is fully visible but image2 is visible only on the approximate extent (0,0), (210, 364).

image2 (observed):

Platforms / Versions

itkwidgets 0.32.6 itk 5.3.0 ipywidgets 7.7.2 ipydatawidgets 4.3.2 notebook 6.1.6

Windows 10 Python 3.8.5

Additional Notes

• The behavior does not occur when the largest image is the first viewed when the notebook runs.
• I believe I have observed this for both 2D and 3D cases in the past, but do not have a good 3D reference on hand.
• The issue does not occur for all possible image sizes. I was unable to reproduce an example for image sizes of <100 pixel widths.

cc @thewtex @PaulHax

[bnmajor]

This appears to be resolved (tested with v1.0a40). Feel free to re-open if needed!