Method: Magick::Image#contrast

Defined in:
ext/RMagick/rmimage.c

#contrast(*args) ⇒ Object

Enhance the intensity differences between the lighter and darker elements of the image. Set sharpen to “true” to increase the image contrast otherwise the contrast is reduced.

Ruby usage:

- @verbatim Image#contrast @endverbatim
- @verbatim Image#contrast(sharpen) @endverbatim

Notes:

- Default sharpen is 0

Parameters:

  • argc —

    number of input arguments

  • argv —

    array of input arguments

  • self —

    this object

Returns:

  • a new image


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# File 'ext/RMagick/rmimage.c', line 3954

VALUE
Image_contrast(int argc, VALUE *argv, VALUE self)
{
    Image *image, *new_image;
    unsigned int sharpen = 0;

    image = rm_check_destroyed(self);
    if (argc > 1)
    {
        rb_raise(rb_eArgError, "wrong number of arguments (%d for 0 or 1)", argc);
    }
    else if (argc == 1)
    {
        sharpen = RTEST(argv[0]);
    }

    new_image = rm_clone_image(image);

    (void) ContrastImage(new_image, sharpen);
    rm_check_image_exception(new_image, DestroyOnError);

    return rm_image_new(new_image);
}