2007.07.14 08:00 "[Tiff] [ANNOUNCE]: Libtiff 3.9.0beta released", by Andrey Kiselev

2007.07.23 14:02 "Re: [Tiff] possible ABI change in 3.9.0 beta?", by Frank Warmerdam

I was looking at the changes from 3.8.2 to 3.9.0 beta, doing my usual inspection for possible ABI changes. I notice that _TIFFRGBAImage has added two new fields:

  uint16 SubsamplingHor;                  /* subsampling factors */
  uint16 SubsamplingVer;

Does this mean that there has been an accidental ABI change between 3.8.2 and 3.9.0? If so, is it a problem that can be fixed before 3.9.0? Otherwise, I will have to patch around this to upload 3.9.0 into debian. Since 4.0.0 will be an ABI changed, I'll save the pain of the tiff transition until then. I haven't yet tested programs that use TIFFRGBAImage compiled with 3.8.2 and run with 3.9.0 beta, but I intend to do that just to be sure.


Good point. I suppose this means there is an ABI change, and versioning information needs to be set appropriately.

I normally think of the TIFFRGBAImage structure as internal to the library but I suppose it is legal for applications to provide custom functions for use with it that are dependent on the internals of this structure so it is indeed public.

Best regards,

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