AWARE SYSTEMS
TIFF and LibTiff Mail List Archive

Thread

2001.04.13 18:32 "Wang Imaging V6 JPEG Encoded TIFFs", by Rex Jolliff
2001.04.24 14:48 "Uneven BitsPerSample files", by Michael O'Rourke
2001.04.24 16:35 "Being able to read the bits per sample array? (vs a single value)", by Michael O'Rourke
2001.04.24 21:49 "Re: Being able to read the bits per sample array? (vs a single value)", by morello

2001.04.24 21:49 "Re: Being able to read the bits per sample array? (vs a single value)", by morello

Looks to me like LibTiff only lets you read TAG_BITSPERSAMPLE as a single value rather than an array.

Anybody know how to read the array (if it exists)?

I haven't looked into this in detail, so maybe someone else can correct me. I might need a solution to this myself soon.

First I think this is a limitation in the library and will need a code change. But there are already examples of array tags which seem to be implemented (according to the documents), such as EXTRASAMPLES. Maybe that is a place to look?

This would probably need to be done as a private hack. Alternatively, isn't there an extension mechanism for adding support for new tags (without altering the mainstream code), perhaps that can also be used to alter the handling of the bits per sample tag.

Having said all that, I am not sure if the code to actually read the scanlines will work. Can of worms.

Tom

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