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HxSub

Synopsis

HxImageRep HxSub(HxImageRep im1, HxImageRep im2)

Input

HxImageRep im1

The first input image

HxImageRep im2

The second input image

Return value

HxImageRep

The substraction of the input images

Description

The function HxSub substracts two images on a pixel-by-pixel basis. Vector pixel types of the same dimension are substracted component wise, while pixel types of different dimensions cannot be summed.

Remarks

Admissable image types

The two input images should have the same dimensionality, the same pixeldimensionality and the same size.

Warning for possible overflow

Substraction can result in an overflow error.

Examples

Substracting two images

#include "HxImageRepGlobalFuncs.h"
#include "HxImageRep.h"

HxImageRep HxSubExample1(HxImageRep im1, HxImageRep im2) {
   im1 = HxImageAsDouble(im1);
   im2 = HxImageAsDouble(im2);
   im1 = HxSub(im1, im2);
   im1 = HxContrastStretch(im1, 255);
   im1 = HxImageAsByte(im1);

   return im1;
}

int main(int argc, char* argv[])
{
    HxImageRep im1 = HxMakeFromFile(argv[1]);
    HxImageRep im2 = HxMakeFromFile(argv[2]);
    im1 = HxSubExample1(im1, im2);
    HxWriteFile(im1, argv[3]);

    return 0;
}

First input image for the HxSub example.

Second input image for the HxSub example.

Output image of the HxSub example.

In this example we substract two (scalar) images. First we convert the image to double images to prevent overflow as much as possible. After substracting the images, we stretch the result and convert it to byte for visualization purposes.

See also

HxAdd, HxMul, HxDiv,

Keywords

Binary, Arithmetic,

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