Test opening single-channel OME-TIFF file

[weiji14]

What I am changing

• Ensure that a single-channel OME-TIFF files can be opened by async-tiff

How I did it

• Created a helper open_remote_tiff utility function to read TIFFs from object stores
• Added a test to open an OME-TIFF file from https://downloads.openmicroscopy.org/images/OME-TIFF/2016-06/bioformats-artificial/single-channel.ome.tif, ensuring that the ImageDescription OME XML metadata is parsed out correctly.

How you can test it

• Run cargo test locally or look at CI logs

Related Issues

• OME-TIFF: Result::unwrap() on an Err value: General("invalid utf-8 sequence of 1 bytes from index 2144") #101

[kylebarron]

Does this close #101?

[kylebarron]

yeah I think it would be better to either check in this file into this repo, or perhaps create an async-tiff-fixtures separate repo that we can check data into.

Assuming this file is large, it would be great if we could extract like a one-pixel or very small subset of this file, while maintaining all header metadata the same.

Or, we could find the size of the last IFD and just clip the existing buffer to that region. So all IFD parsing would succeed but any image loading would fail as the image data is past the byte region checked in to the test fixture.

[weiji14]

This file is 74.3KB, not huge but having many test files like these will add up (the vendored images from #28 add up to 4.5MB already 🙂).

Probably best to bring this discussion over to #23.

[weiji14]

Does this close #101?

No it doesn't. I haven't applied the String::from_utf8_lossy patch mentioned at #101 (comment), nor handled the line causing the panic on the pyo3 side yet. Will do that in another PR.