cimg2num.cpp File Reference

#include "cimg2num.h"
#include "img2num.h"
#include "img2num/Error.h"
#include <cstring>

Include dependency graph for cimg2num.cpp:

Go to the source code of this file.

Functions
img2num_ImageToSvgConfig	img2num_ImageToSvgConfig_default (void)
void	img2num_gaussian_blur_fft (uint8_t *image, size_t width, size_t height, double sigma)
	Apply a Gaussian blur to an image using FFT.
void	img2num_invert_image (uint8_t *image, int width, int height)
	Invert the pixel values of an image.
void	img2num_threshold_image (uint8_t *ptr, const int width, const int height, const int num_thresholds)
	Apply a thresholding operation to an image.
void	img2num_black_threshold_image (uint8_t *ptr, const int width, const int height, const int num_thresholds)
	Apply black-thresholding to an image.
void	img2num_kmeans (const uint8_t *data, uint8_t *out_data, int32_t *out_labels, const int32_t width, const int32_t height, const int32_t k, const int32_t max_iter, const uint8_t color_space)
	Perform k-means clustering on image data.
void	img2num_bilateral_filter (uint8_t *image, size_t width, size_t height, double sigma_spatial, double sigma_range, uint8_t color_space)
	Apply bilateral filtering to an image.
char *	img2num_labels_to_svg (const uint8_t *data, const int32_t *labels, const int width, const int height, const int min_area, const int min_thickness)
	Convert labeled regions of an image into an SVG string.
char *	img2num_image_to_svg (const uint8_t *data, const int width, const int height, const img2num_ImageToSvgConfig *config)
	Convert labeled regions of an image into an SVG string.

Function Documentation

img2num_bilateral_filter()

void img2num_bilateral_filter	(	uint8_t *	image,
		size_t	width,
		size_t	height,
		double	sigma_spatial,
		double	sigma_range,
		uint8_t	color_space
	)

Apply bilateral filtering to an image.

Parameters

image	Pointer to RGBA pixel buffer.
width	Width of the image in pixels.
height	Height of the image in pixels.
sigma_spatial	Standard deviation for spatial Gaussian (proximity weight).
sigma_range	Standard deviation for range Gaussian (intensity similarity weight).
color_space	Color space flag (0 = CIE LAB, 1 = RGB).

Note

The filter modifies the image buffer in-place.

Dox File: doxygen/img2num.h.dox

Definition at line 80 of file cimg2num.cpp.

  {
    img2num::clear_last_error_and_catch(
        img2num::bilateral_filter, image, width, height, sigma_spatial, sigma_range, color_space
    );
}

img2num_black_threshold_image()

void img2num_black_threshold_image	(	uint8_t *	ptr,
		const int	width,
		const int	height,
		const int	num_thresholds
	)

Apply black-thresholding to an image.

Parameters

ptr	Pointer to the image buffer.
width	Width of the image in pixels.
height	Height of the image in pixels.
num_thresholds	Number of thresholds to apply.

Note

Similar to threshold_image but prioritizes darker pixels.

Dox File: doxygen/img2num.h.dox

Definition at line 63 of file cimg2num.cpp.

  {
    img2num::clear_last_error_and_catch(
        img2num::black_threshold_image, ptr, width, height, num_thresholds
    );
}

img2num_gaussian_blur_fft()

void img2num_gaussian_blur_fft	(	uint8_t *	image,
		size_t	width,
		size_t	height,
		double	sigma
	)

Apply a Gaussian blur to an image using FFT.

Parameters

image	Pointer to the image buffer (RGBA).
width	Width of the image in pixels.
height	Height of the image in pixels.
sigma	Standard deviation for Gaussian kernel.

Note

The operation modifies the image buffer in-place.

Dox File: doxygen/img2num.h.dox

Definition at line 47 of file cimg2num.cpp.

                                                                                          {
    img2num::clear_last_error_and_catch(img2num::gaussian_blur_fft, image, width, height, sigma);
}

img2num_image_to_svg()

char * img2num_image_to_svg	(	const uint8_t *	data,
		const int	width,
		const int	height,
		const img2num_ImageToSvgConfig *	config
	)

Convert labeled regions of an image into an SVG string.

Parameters

data	Pointer to image data buffer.
width	Width of the image in pixels.
height	Height of the image in pixels.
config	img2num_ImageToSvgConfig Configuration Struct. ‍See img2num::ImageToSvgConfig.

Returns

std::string An SVG string containing data roughly approximate to the input image.

Note

Dox File: doxygen/img2num.h.dox

Definition at line 109 of file cimg2num.cpp.

  {
    img2num_ImageToSvgConfig default_cfg {img2num_ImageToSvgConfig_default()};
 
    const img2num_ImageToSvgConfig& cfg {config ? *config : default_cfg};
 
    char* result {nullptr};
 
    img2num::clear_last_error_and_catch(
        [&](const uint8_t* d, const int w, const int h) {
            std::string svg {img2num::image_to_svg(d, w, h, to_cpp(cfg))};
 
            result = static_cast<char*>(std::malloc(svg.size() + 1));
            if (!result) {
                return; // Allocation failed
            }
            std::memcpy(result, svg.c_str(), svg.size() + 1);
        },
        data, width, height
    );
 
    return result;
}

References img2num_ImageToSvgConfig_default().

Here is the call graph for this function:

img2num_ImageToSvgConfig_default()

img2num_ImageToSvgConfig img2num_ImageToSvgConfig_default

(

void

)

Definition at line 42 of file cimg2num.cpp.

                                                                {
    // Use the defaults from the C++ struct
    return to_c(img2num::ImageToSvgConfig {});
}

Referenced by img2num_image_to_svg().

Here is the caller graph for this function:

img2num_invert_image()

void img2num_invert_image	(	uint8_t *	ptr,
		int	width,
		int	height
	)

Invert the pixel values of an image.

Parameters

ptr	Pointer to the image buffer.
width	Width of the image in pixels.
height	Height of the image in pixels.

Note

Each pixel value is replaced by 255 - original_value.

Dox File: doxygen/img2num.h.dox

Definition at line 51 of file cimg2num.cpp.

                                                                 {
    img2num::clear_last_error_and_catch(img2num::invert_image, image, width, height);
}

img2num_kmeans()

void img2num_kmeans	(	const uint8_t *	data,
		uint8_t *	out_data,
		int32_t *	out_labels,
		const int32_t	width,
		const int32_t	height,
		const int32_t	k,
		const int32_t	max_iter,
		const uint8_t	color_space
	)

Perform k-means clustering on image data.

Parameters

data	Pointer to input image data buffer.
out_data	Pointer to output buffer where clustered pixel values are stored.
out_labels	Pointer to output buffer for cluster labels per pixel.
width	Width of the image in pixels.
height	Height of the image in pixels.
k	Number of clusters to compute.
max_iter	Maximum number of iterations for the algorithm.
color_space	Color space flag (0 = CIE LAB, 1 = RGB).

Note

The function does not modify the input buffer.

Dox File: doxygen/img2num.h.dox

Definition at line 71 of file cimg2num.cpp.

  {
    img2num::clear_last_error_and_catch(
        img2num::kmeans, data, out_data, out_labels, width, height, k, max_iter, color_space
    );
}

img2num_labels_to_svg()

char * img2num_labels_to_svg	(	const uint8_t *	data,
		const int32_t *	labels,
		const int	width,
		const int	height,
		const int	min_area,
		const int	min_thickness
	)

Convert labeled regions of an image into an SVG string.

Parameters

data	Pointer to image data buffer.
labels	Pointer to label buffer, indicating region for each pixel.
width	Width of the image in pixels.
height	Height of the image in pixels.
min_area	Minimum area (in pixels) for a region to be included in the SVG.

Returns

std::string A valid SVG string containing the data.

Note

Dox File: doxygen/img2num.h.dox

Definition at line 89 of file cimg2num.cpp.

  {
    char* result {nullptr};
    img2num::clear_last_error_and_catch(
        [&](const uint8_t* d, const int32_t* l, const int w, const int h, const int min_a,
            const int min_t) {
            std::string svg {img2num::labels_to_svg(d, l, w, h, min_a, min_t)};
            result = static_cast<char*>(std::malloc(svg.size() + 1));
            if (!result) {
                return; // Allocation failed
            }
            std::memcpy(result, svg.c_str(), svg.size() + 1);
        },
        data, labels, width, height, min_area, min_thickness
    );
    return result;
}

img2num_threshold_image()

void img2num_threshold_image	(	uint8_t *	ptr,
		const int	width,
		const int	height,
		const int	num_thresholds
	)

Apply a thresholding operation to an image.

Parameters

ptr	Pointer to the image buffer.
width	Width of the image in pixels.
height	Height of the image in pixels.
num_thresholds	Number of thresholds to apply.

Note

Thresholds split pixel intensity ranges into discrete levels.

Dox File: doxygen/img2num.h.dox

Definition at line 55 of file cimg2num.cpp.

  {
    img2num::clear_last_error_and_catch(
        img2num::threshold_image, ptr, width, height, num_thresholds
    );
}