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// Copyright (C) 2006 Davis E. King (davis@dlib.net)
// License: Boost Software License See LICENSE.txt for the full license.
#undef DLIB_THRESHOLDINg_ABSTRACT_
#ifdef DLIB_THRESHOLDINg_ABSTRACT_
#include "../pixel.h"
namespace dlib
{
// ----------------------------------------------------------------------------------------
const unsigned char on_pixel = 255;
const unsigned char off_pixel = 0;
// ----------------------------------------------------------------------------------------
template <
typename in_image_type,
typename out_image_type
>
void threshold_image (
const in_image_type& in_img,
out_image_type& out_img,
typename pixel_traits<typename in_image_type::type>::basic_pixel_type thresh
);
/*!
requires
- in_image_type == is an implementation of array2d/array2d_kernel_abstract.h
- out_image_type == is an implementation of array2d/array2d_kernel_abstract.h
- pixel_traits<typename out_image_type::type>::grayscale == true
- pixel_traits<typename in_image_type::type>::has_alpha == false
- pixel_traits<typename out_image_type::type>::has_alpha == false
ensures
- #out_img == the thresholded version of in_img (in_img is converted to a grayscale
intensity image if it is color). Pixels in in_img with grayscale values >= thresh
have an output value of on_pixel and all others have a value of off_pixel.
- #out_img.nc() == in_img.nc()
- #out_img.nr() == in_img.nr()
!*/
template <
typename image_type
>
void threshold_image (
image_type& img,
typename pixel_traits<typename image_type::type>::basic_pixel_type thresh
);
/*!
requires
- it is valid to call threshold_image(img,img,thresh);
ensures
- calls threshold_image(img,img,thresh);
!*/
// ----------------------------------------------------------------------------------------
template <
typename in_image_type,
typename out_image_type
>
void auto_threshold_image (
const in_image_type& in_img,
out_image_type& out_img
);
/*!
requires
- in_image_type == is an implementation of array2d/array2d_kernel_abstract.h
- out_image_type == is an implementation of array2d/array2d_kernel_abstract.h
- pixel_traits<typename out_image_type::type>::grayscale == true
- pixel_traits<typename in_image_type::type>::has_alpha == false
- pixel_traits<typename out_image_type::type>::has_alpha == false
- pixel_traits<typename in_image_type::type>::is_unsigned == true
- pixel_traits<typename out_image_type::type>::is_unsigned == true
ensures
- #out_img == the thresholded version of in_img (in_img is converted to a grayscale
intensity image if it is color). Pixels in in_img with grayscale values >= thresh
have an output value of on_pixel and all others have a value of off_pixel.
- The thresh value used is determined by performing a k-means clustering
on the input image histogram with a k of 2. The point between the two
means found is used as the thresh value.
- #out_img.nc() == in_img.nc()
- #out_img.nr() == in_img.nr()
!*/
template <
typename image_type
>
void auto_threshold_image (
image_type& img
);
/*!
requires
- it is valid to call auto_threshold_image(img,img);
ensures
- calls auto_threshold_image(img,img);
!*/
// ----------------------------------------------------------------------------------------
template <
typename in_image_type,
typename out_image_type
>
void hysteresis_threshold (
const in_image_type& in_img,
out_image_type& out_img,
typename pixel_traits<typename in_image_type::type>::basic_pixel_type lower_thresh,
typename pixel_traits<typename in_image_type::type>::basic_pixel_type upper_thresh
);
/*!
requires
- in_image_type == is an implementation of array2d/array2d_kernel_abstract.h
- out_image_type == is an implementation of array2d/array2d_kernel_abstract.h
- pixel_traits<typename out_image_type::type>::grayscale == true
- pixel_traits<typename in_image_type::type>::has_alpha == false
- pixel_traits<typename out_image_type::type>::has_alpha == false
- lower_thresh <= upper_thresh
- is_same_object(in_img, out_img) == false
ensures
- #out_img == the hysteresis thresholded version of in_img (in_img is converted to a
grayscale intensity image if it is color). Pixels in in_img with grayscale
values >= upper_thresh have an output value of on_pixel and all others have a
value of off_pixel unless they are >= lower_thresh and are adjacent to a pixel
with a value >= upper_thresh in which case they have a value of on_pixel.
- #out_img.nc() == in_img.nc()
- #out_img.nr() == in_img.nr()
!*/
// ----------------------------------------------------------------------------------------
}
#endif // DLIB_THRESHOLDINg_ABSTRACT_
|
