2009.02.12 21:10 "[Tiff] warning and errors", by Philip Watkinson

2009.02.12 23:06 "Re: [Tiff] warning and errors", by Philip Watkinson

We want to use Libtiff in a production evironment. We don't want warnings/error messages unless there is a critical error (the image is corrupt).

  1. Is there a listing of warnings which indicate that the image is corrupt?
  2. If Libtiff generates an error, can I assume it is a critical error?

Regards, Philip

-----Original Message-----

I'm using Libtiff and getting the warning "unknown field with tag

> 34665

(0x8769) encountered". Joris stated the following about the tag in

> some

correspondence:

The warning doesn't really matter, unless you're specifically

> interested in the EXIF information of course. Image decoding using > LibTiff should still work fine, the warning can be safely ignored.

Can I assume that all warning still produce a good image?

No, this is not a safe assumption, but it is true that the "unknown field" warning is harmless. It normally just indicates the presents of a (possibly private) tag not in the core standard.

There are some warnings that may indicate the image is likely to be wrong. But generally speaking the library will attempt to continue processing and you are *likely* to get something useful when you see warnings.

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