Legacy ImageMagick Discussions Archive

Hi. I can't seem to find any method of testing if Genesis or Terminus have been called. Do functions that test this exist?

I'm developing an application that uses MagickWand. It calls genesis and terminus in main, so this isn't a problem within my application. However, my application takes plugins that handle specific functionality. The idea being that others would develop these modules. In one of my reference modules, I'd like to use MagickWand. This is where I'm having my problem. If I call Genesis and Terminus in my module init and finalize functions, I get this error:

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magick/semaphore.c:290: LockSemaphoreInfo: Assertion `semaphore_info != (SemaphoreInfo *) ((void *)0)' failed.

I'm assuming this is caused by a second call to Genesis.

This leaves me with an unpleasant choice: I can either not use MagickWand in my module, and try to use a different library and add an extra dependency, or I can use my knowledge that Genesis has been called in the main application and not worry about it. However, while that's an assumption that I can make, I can't expect that others have implementation details of my application.

Am I mising something? Am I just approaching this the wrong way? Any help is appreciated!

Try IsMagickInstantiated().

That would seem to be exactly what I'm looking for! Thank you for the quick reply!

That said, I can't find that function anywhere in the API documentation I've been using. (http://www.imagemagick.org/script/magick-wand.php) Is there some extra documentation somewhere that I missed?

Well, I just tried to run my app using IsMagickInstantiated(), and I'm having some more issues. No matter what, IsMagickInstantiated always returns 0. So, if I do this:

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MagickWandGenesis();
g_assert(IsMagickInstantiated());

I get an assertion failure:

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ERROR:photo_strip.c:84:dmp_pb_photo_strip_init: assertion failed: (IsMagickInstantiated())

Running through the debugger also shows this behavior.

I'm using ImageMagick 6.7.7.10 from the repositories with Ubuntu 13.04

Thanks in advance for your help!

Can you try ImageMaagick 6.8.8-1, the current release? In the mean-time we'll add IsMagickWandInstantiated() to the MagickWand API in the next release, 6.8.8-2.

Ok, I just installed ImageMagick 6.8.8-1 from source. I gave this block of code a shot:

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MagickWandGenesis();
const gchar * testing = MagickGetVersion(NULL);
g_printf("%s", testing);
g_assert(IsMagickInstantiated());

...and I got the same result:

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ERROR:photo_strip.c:88:dmp_pb_photo_strip_init: assertion failed: (IsMagickInstantiated())
ImageMagick 6.8.8-1 Q16 x86_64 2014-01-03 http://www.imagemagick.org

I suppose going forward I can go back to tracking this manually within my application. Maybe I'll provide a callback that modules can use to check the state of MagickWand until the new IsMagickWandInstantiated() function is implemented.

Thanks for your help!

We can reproduce the problem you posted and have a patch in ImageMagick 6.8.8-2 Beta, available by sometime tomorrow. Thanks.

Legacy ImageMagick Discussions Archive

Test if MagickWandGenesis() or MagickWandTerminus() called

Test if MagickWandGenesis() or MagickWandTerminus() called

Re: Test if MagickWandGenesis() or MagickWandTerminus() call

Re: Test if MagickWandGenesis() or MagickWandTerminus() call

Re: Test if MagickWandGenesis() or MagickWandTerminus() call

Re: Test if MagickWandGenesis() or MagickWandTerminus() call

Re: Test if MagickWandGenesis() or MagickWandTerminus() call

Re: Test if MagickWandGenesis() or MagickWandTerminus() call