Morphology in MagickWand.

[rpatelob]

What is the equivalent of below CLI into C?

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-morphology Distance:-1 Euclidean:5,1000

C code.

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  KernelInfo *kernel;
  const char *kernel_string = "EuclideanKernel";
  ExceptionInfo * exc = AcquireExceptionInfo();
  kernel = AcquireKernelInfo(kernel_string,exc);
  MagickMorphologyImage(wand2, DistanceMorphology, 1000, kernel);

[snibgo]

Please, always state what version of IM you are using.

const char *kernel_string = "EuclideanKernel";
ExceptionInfo * exc = AcquireExceptionInfo();
kernel = AcquireKernelInfo(kernel_string,exc);

I suggest you read the documentation on AcquireKernelInfo(). The source code for that function explains the parameter. See also http://www.imagemagick.org/Usage/morphology/ for a fuller description.

[rpatelob]

Thank you snibgo for the suggestion. And I'm using Version: ImageMagick 7.0.5-5 Q16 x86_64 2017-04-26 http://www.imagemagick.org.

[el_supremo]

I've replicated one of Anthony's morphology examples using MagickWand.

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#ifdef MORPHOLOGY_1
// https://www.imagemagick.org/discourse-server/viewtopic.php?f=6&t=31863

// Try one of Anthony's morphology examples first:
// convert man.gif   -morphology Erode Octagon  erode_man.gif
#include <windows.h>
#include <wand/magick_wand.h>
void test_wand(void)
{
	MagickWand *mw = NULL;
	KernelInfo *ki;
	char kernel[512];

	MagickWandGenesis();

	/* Create a wand */
	mw = NewMagickWand();

	/* Read the input image */
	MagickReadImage(mw,"man.gif");

	ki = AcquireKernelInfo("Octagon");
	if(ki == NULL) {
		MessageBox(NULL,"ki NULL","",MB_OK);
		if(mw) mw = DestroyMagickWand(mw);
		MagickWandTerminus();
		exit(10);
	}
	if(!MagickMorphologyImage(mw, ErodeMorphology, 1, ki)) {
		MessageBox(NULL,"Failed","",MB_OK);
	} else {
		/* write it */
		MagickWriteImage(mw,"man_erode_octagon.gif");
	}

	/* Tidy up */
	ki=DestroyKernelInfo(ki);
	if(mw) mw = DestroyMagickWand(mw);
	MagickWandTerminus();
}
#endif

I presume that "-morphology Distance:-1 Euclidean:5,1000" would require:

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	ki = AcquireKernelInfo("Euclidean:5,1000");

and

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if(!MagickMorphologyImage(mw, DistanceMorphology, -1, ki)) {

Pete

[rpatelob]

Hello el_supremo,

Finally I got my solution this way.

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-morphology Distance:-1 Euclidean:5,1000

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  KernelInfo *kernel;
  GeometryInfo geometry;
  geometry.sigma = 1000;
  geometry.rho = 5;
  ExceptionInfo * exc = AcquireExceptionInfo();
  kernel = AcquireKernelBuiltIn(EuclideanKernel, &geometry, exc);
  MagickMorphologyImage(wand2, DistanceMorphology, 1, kernel);

Thank you for the Example. Could you please check my code? I have got the result so haven't spend so much time on it.

[snibgo]

If you need iterations of -1 at the command line, I expect you need -1 in the call to MagickMorphologyImage. But I haven't tested this, and "-1" probably has no effect for "Distance".

To check your code, you can test whether the code gives the same result as the command line.

[el_supremo]

I forgot to note that the code I wrote used IM version 6.9.7. It appears that the code you are using is IM v7 - I need to get around to upgrading!
In V7 the signature is:

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KernelInfo *AcquireKernelInfo(const char *kernel_string,  ExceptionInfo *exception)

but in V6 it is:

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KernelInfo *AcquireKernelInfo(const char *kernel_string)

Other than that, I agree with @snibgo that if the command line version needed -1, then the code should use -1 too, although it is possible that -1 and 1 would give the same result in your case.

Pete