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openpreserve / jhove

File validation and characterisation.
http://jhove.openpreservation.org
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BigTIFF support? #687

Open fiendish opened 3 years ago

fiendish commented 3 years ago

The TIFF-hul module demands magic number 42

https://github.com/openpreserve/jhove/blob/47f077fcb09d3dd5720aeeb4abf27de5dac48d19/jhove-modules/tiff-hul/src/main/java/edu/harvard/hul/ois/jhove/module/TiffModule.java#L523

which means that BigTIFFs (magic number 43) don't validate: 

  ErrorMessage: No TIFF magic number: 43
   ID: TIFF-HUL-21
   Offset: 2

Is there any plan to support the BigTIFF variant?

carlwilson commented 2 years ago

We hadn't planned to as there's been no requests to so far. The changes to the format specification seem fairly straightforward but we don't have any examples of the format. What's the source of these images and do you have any sample files we could use to investigate further.

fiendish commented 2 years ago

I did in 2021, but not anymore. 🤷‍♂️ If I remember correctly, the context for the inquiry was that the Aperio SVS slide scanner image format is a TIFF with an image pyramid and some custom metadata headers, and some of them use BigTIFF.

samalloing commented 2 years ago

Hii Carl,

You find sample files at: https://www.awaresystems.be/imaging/tiff/bigtiff.html

Sam

carlwilson commented 2 years ago

I'd agree that support would be good, but only if the development effort is reasonable/manageable. @samalloing thanks for the link with the samples which I've taken a quick look at. The set of samples isn't huge, but it provides enough information to test a simple implementation. This won't get looked at before the upcoming release but will investigate and give a yes or no after that.