Document Zeiss CZI

[bgilbert]

For openslide/openslide#396.

[openslide-bot]

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[bgilbert]

@iewchen Could you take a look and make sure I haven't misstated anything?

[iewchen]

czi-format.md

I have made some minor edits. Please see the attached file.

Edit: correct spelling. czi-format.md

[bgilbert]

Updated based on your feedback, thanks. Could you take another look?

I noticed that you dropped the statement that Label and SlidePreview have one subblock of uncompressed pixel data, 24 bpp and 48 bpp respectively. Is that not correct? OpenSlide doesn't enforce the 24bpp/48bpp part but does currently assume those images are single-subblock and uncompressed.

[iewchen]

Looks good.

The one subblock of uncompressed pixel data, 24 bpp and 48 bpp are observations, they are not in the CZI specification.

For SlidePreview, other cameras can be used, such as use monochrome camera to capture preview in fluorescence, therefore it may be stored as 16bpp , although I haven't tried.

All Label and SlidePreview I saw so far have only one subblock and are uncompressed. They do not have the scene dimension. The one subblock seems to be a good choice for color images, since their size are less than 2000x2000. I don't quite understand why they are stored as uncompressed.

[bgilbert]

Got it, thanks. I've dropped the statement.