Important Fix for Delphi users: FPU exceptions

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Walter-Tracker Supp
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Joined: Mon Jun 13, 2011 5:10 pm

Important Fix for Delphi users: FPU exceptions

Post by Walter-Tracker Supp » Wed Apr 03, 2013 8:53 pm

In light of some discussions with one of our Delphi users we have recognized the need to fix an issue with the ocrtools.dll which could impact Delphi applications in certain environment configurations.

The fixed DLLs are version numbered 1.0.13.x and will be on our website very shortly (you can check DLL version in Windows Explorer by right-clicking the DLL and selecting "properties").

A little background: in some algorithms, including the fundamental OCR algorithms we use, it is preferable (for performance reasons, and sometimes mathematics) to ignore some floating point exceptions (e.g. divide by zero) when the "bad" results of these operations do not negatively impact the algorithm. The default behaviour in MSVC++ is to ignore these hardware exceptions thrown by the FPU, but Delphi applications do not suppress them.

The newest DLLs explicitly disable the relevant FP exceptions during algorithms for which throwing these exceptions is not desirable, and then sets the previous exception handling state after execution (so that exceptions in your own Delphi code will be handled as normal).

This change has been made in version 1.0.13.x of the ocrtools DLLs available on our website shortly (likely within an hour or so after this post). The live DLLs will be updated first, and demo versions in the demo installer will be updated as soon as our installer gurus can get this done.

We apologize to any users (Delphi users, in particular) who have been inconvenienced by this behaviour.


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