Functions for estimation of image histogram. More...

Functions
SIMD_API void	SimdAbsSecondDerivativeHistogram (const uint8_t src, size_t width, size_t height, size_t stride, size_t step, size_t indent, uint32_t histogram)
	Calculates histogram of second derivative for 8-bit gray image. More...

SIMD_API void	SimdHistogram (const uint8_t src, size_t width, size_t height, size_t stride, uint32_t histogram)
	Calculates histogram for 8-bit gray image. More...

SIMD_API void	SimdHistogramMasked (const uint8_t src, size_t srcStride, size_t width, size_t height, const uint8_t mask, size_t maskStride, uint8_t index, uint32_t *histogram)
	Calculates histogram for 8-bit gray image with using mask. More...

SIMD_API void	SimdHistogramConditional (const uint8_t src, size_t srcStride, size_t width, size_t height, const uint8_t mask, size_t maskStride, uint8_t value, SimdCompareType compareType, uint32_t *histogram)
	Calculates histogram of 8-bit gray image for those points when mask points satisfying certain condition. More...

SIMD_API void	SimdNormalizedColors (const uint32_t histogram, uint8_t colors)
	Gets normalized color map for given histogram. More...

SIMD_API void	SimdChangeColors (const uint8_t src, size_t srcStride, size_t width, size_t height, const uint8_t colors, uint8_t *dst, size_t dstStride)
	Changes colors for 8-bit gray image with using of color map. More...

SIMD_API void	SimdNormalizeHistogram (const uint8_t src, size_t srcStride, size_t width, size_t height, uint8_t dst, size_t dstStride)
	Normalizes histogram for 8-bit gray image. More...

template<template< class > class A>
SIMD_INLINE void	AbsSecondDerivativeHistogram (const View< A > &src, size_t step, size_t indent, uint32_t *histogram)
	Calculates histogram of second derivative for 8-bit gray image. More...

template<template< class > class A>
SIMD_INLINE void	Histogram (const View< A > &src, uint32_t *histogram)
	Calculates histogram for 8-bit gray image. More...

template<template< class > class A>
SIMD_INLINE void	HistogramMasked (const View< A > &src, const View< A > &mask, uint8_t index, uint32_t *histogram)
	Calculates histogram for 8-bit gray image with using mask. More...

template<template< class > class A>
SIMD_INLINE void	HistogramConditional (const View< A > &src, const View< A > &mask, uint8_t value, SimdCompareType compareType, uint32_t *histogram)
	Calculates histogram of 8-bit gray image for those points when mask points satisfying certain condition. More...

template<template< class > class A>
SIMD_INLINE void	ChangeColors (const View< A > &src, const uint8_t *colors, View< A > &dst)
	Changes colors for 8-bit gray image with using of color map. More...

template<template< class > class A>
SIMD_INLINE void	NormalizeHistogram (const View< A > &src, View< A > &dst)
	Normalizes histogram for 8-bit gray image. More...

SIMD_INLINE double	Mean (const uint32_t *histogram)
	Calculates mean from image histogram. More...

SIMD_INLINE uint8_t	OtsuThreshold (const uint32_t *histogram)
	Calculates Otsu threhsold from image histogram. More...

Detailed Description

Functions for estimation of image histogram.

Function Documentation

◆ SimdAbsSecondDerivativeHistogram()

void SimdAbsSecondDerivativeHistogram	(	const uint8_t *	src,
		size_t	width,
		size_t	height,
		size_t	stride,
		size_t	step,
		size_t	indent,
		uint32_t *	histogram
	)

Calculates histogram of second derivative for 8-bit gray image.

For all points except the boundary (defined by parameter indent):

dx = abs(src[x, y] - average(src[x+step, y], src[x-step, y]));
dy = abs(src[x, y] - average(src[x, y+step], src[x, y-step]));
histogram[max(dx, dy)]++;

Note: This function has a C++ wrapper Simd::AbsSecondDerivativeHistogram(const View<A>& src, size_t step, size_t indent, uint32_t * histogram).

Parameters

[in]	src	- a pointer to pixels data of input 8-bit gray image.
[in]	width	- an image width.
[in]	height	- an image height.
[in]	stride	- a row size of the image.
[in]	step	- a step for second derivative calculation.
[in]	indent	- a indent from image boundary.
[out]	histogram	- a pointer to histogram (array of 256 unsigned 32-bit values).

◆ SimdHistogram()

void SimdHistogram	(	const uint8_t *	src,
		size_t	width,
		size_t	height,
		size_t	stride,
		uint32_t *	histogram
	)

Calculates histogram for 8-bit gray image.

For all points:

histogram[src[i]]++.

Note: This function has a C++ wrapper Simd::Histogram(const View<A>& src, uint32_t * histogram).

Parameters

[in]	src	- a pointer to pixels data of input 8-bit gray image.
[in]	width	- an image width.
[in]	height	- an image height.
[in]	stride	- a row size of the image.
[out]	histogram	- a pointer to histogram (array of 256 unsigned 32-bit values).

◆ SimdHistogramMasked()

void SimdHistogramMasked	(	const uint8_t *	src,
		size_t	srcStride,
		size_t	width,
		size_t	height,
		const uint8_t *	mask,
		size_t	maskStride,
		uint8_t	index,
		uint32_t *	histogram
	)

Calculates histogram for 8-bit gray image with using mask.

For every point:

if(mask[i] == index)
    histogram[src[i]]++.

Note: This function has a C++ wrapper Simd::HistogramMasked(const View<A> & src, const View<A> & mask, uint8_t index, uint32_t * histogram).

Parameters

[in]	src	- a pointer to pixels data of input 8-bit gray image.
[in]	srcStride	- a row size of the image.
[in]	width	- an image width.
[in]	height	- an image height.
[in]	mask	- a pointer to pixels data of the mask 8-bit image.
[in]	maskStride	- a row size of the mask image.
[in]	index	- a mask index.
[out]	histogram	- a pointer to histogram (array of 256 unsigned 32-bit values).

◆ SimdHistogramConditional()

void SimdHistogramConditional	(	const uint8_t *	src,
		size_t	srcStride,
		size_t	width,
		size_t	height,
		const uint8_t *	mask,
		size_t	maskStride,
		uint8_t	value,
		SimdCompareType	compareType,
		uint32_t *	histogram
	)

Calculates histogram of 8-bit gray image for those points when mask points satisfying certain condition.

For every point:

if(compare(mask[x, y], value))
    histogram[src[x, y]]++.

Note: This function has a C++ wrapper Simd::HistogramConditional(const View<A>& src, const View<A>& mask, uint8_t value, SimdCompareType compareType, uint32_t * histogram).

Parameters

[in]	src	- a pointer to pixels data of input 8-bit gray image.
[in]	srcStride	- a row size of the image.
[in]	width	- an image width.
[in]	height	- an image height.
[in]	mask	- a pointer to pixels data of the mask 8-bit image.
[in]	maskStride	- a row size of the mask image.
[in]	value	- a second value for compare operation.
[in]	compareType	- a compare operation type (see SimdCompareType).
[out]	histogram	- a pointer to histogram (array of 256 unsigned 32-bit values).

◆ SimdNormalizedColors()

void SimdNormalizedColors	(	const uint32_t *	histogram,
		uint8_t *	colors
	)

Gets normalized color map for given histogram.

Parameters

[in]	histogram	- a pointer to histogram (array of 256 unsigned 32-bit values).
[out]	colors	- a pointer to the color map (array of 256 unsigned 8-bit values).

◆ SimdChangeColors()

void SimdChangeColors	(	const uint8_t *	src,
		size_t	srcStride,
		size_t	width,
		size_t	height,
		const uint8_t *	colors,
		uint8_t *	dst,
		size_t	dstStride
	)

Changes colors for 8-bit gray image with using of color map.

The input and output 8-bit gray images must have the same size. Algorithm description:

for(y = 0; y < height; ++y)
    for(x = 0; x < width; ++x)
        dst[x, y] = colors[src[x, y]];

Note: This function has a C++ wrapper Simd::ChangeColors(const View<A> & src, const uint8_t * colors, View<A> & dst).

Parameters

[in]	src	- a pointer to pixels data of input 8-bit gray image.
[in]	srcStride	- a row size of the image.
[in]	width	- an image width.
[in]	height	- an image height.
[in]	colors	- a pointer to the color map (array of 256 unsigned 8-bit values).
[out]	dst	- a pointer to pixels data of output 8-bit gray image.
[in]	dstStride	- a row size of the output gray image.

◆ SimdNormalizeHistogram()

void SimdNormalizeHistogram	(	const uint8_t *	src,
		size_t	srcStride,
		size_t	width,
		size_t	height,
		uint8_t *	dst,
		size_t	dstStride
	)

Normalizes histogram for 8-bit gray image.

The input and output 8-bit gray images must have the same size.

Note: This function has a C++ wrapper Simd::NormalizeHistogram(const View<A> & src, View<A> & dst).

Parameters

[in]	src	- a pointer to pixels data of input 8-bit gray image.
[in]	srcStride	- a row size of the image.
[in]	width	- an image width.
[in]	height	- an image height.
[out]	dst	- a pointer to pixels data of output 8-bit image with normalized histogram.
[in]	dstStride	- a row size of the output image.

◆ AbsSecondDerivativeHistogram()

void AbsSecondDerivativeHistogram	(	const View< A > &	src,
		size_t	step,
		size_t	indent,
		uint32_t *	histogram
	)

Calculates histogram of second derivative for 8-bit gray image.

For all points except the boundary (defined by parameter indent):

dx = abs(src[x, y] - average(src[x+step, y], src[x-step, y]));
dy = abs(src[x, y] - average(src[x, y+step], src[x, y-step]));
histogram[max(dx, dy)]++;

Note: This function is a C++ wrapper for function SimdAbsSecondDerivativeHistogram.

Parameters

[in]	src	- an input 8-bit gray image.
[in]	step	- a step for second derivative calculation.
[in]	indent	- a indent from image boundary.
[out]	histogram	- a pointer to histogram (array of 256 unsigned 32-bit values).

◆ Histogram()

void Histogram	(	const View< A > &	src,
		uint32_t *	histogram
	)

Calculates histogram for 8-bit gray image.

For all points:

histogram[src[i]]++.

Note: This function is a C++ wrapper for function SimdHistogram.

Parameters

[in]	src	- an input 8-bit gray image.
[out]	histogram	- a pointer to histogram (array of 256 unsigned 32-bit values).

◆ HistogramMasked()

void HistogramMasked	(	const View< A > &	src,
		const View< A > &	mask,
		uint8_t	index,
		uint32_t *	histogram
	)

Calculates histogram for 8-bit gray image with using mask.

For every point:

if(mask[i] == index)
    histogram[src[i]]++.

Note: This function is a C++ wrapper for function SimdHistogramMasked.

Parameters

[in]	src	- an input 8-bit gray image.
[in]	mask	- a mask 8-bit image.
[in]	index	- a mask index.
[out]	histogram	- a pointer to histogram (array of 256 unsigned 32-bit values).

◆ HistogramConditional()

void HistogramConditional	(	const View< A > &	src,
		const View< A > &	mask,
		uint8_t	value,
		SimdCompareType	compareType,
		uint32_t *	histogram
	)

Calculates histogram of 8-bit gray image for those points when mask points satisfying certain condition.

For every point:

if(compare(mask[x, y], value))
    histogram[src[x, y]]++.

Note: This function is a C++ wrapper for function SimdHistogramConditional.

Parameters

[in]	src	- an input 8-bit gray image.
[in]	mask	- a mask 8-bit image.
[in]	value	- a second value for compare operation.
[in]	compareType	- a compare operation type (see SimdCompareType).
[out]	histogram	- a pointer to histogram (array of 256 unsigned 32-bit values).

◆ ChangeColors()

void ChangeColors	(	const View< A > &	src,
		const uint8_t *	colors,
		View< A > &	dst
	)

Changes colors for 8-bit gray image with using of color map.

The input and output 8-bit gray images must have the same size. Algorithm description:

for(y = 0; y < height; ++y)
    for(x = 0; x < width; ++x)
        dst[x, y] = colors[src[x, y]];

Note: This function is a C++ wrapper for function SimdChangeColors.

Parameters

[in]	src	- an input 8-bit gray image.
[in]	colors	- a pointer to the color map (array of 256 unsigned 8-bit values).
[out]	dst	- an output 8-bit gray image.

◆ NormalizeHistogram()

void NormalizeHistogram	(	const View< A > &	src,
		View< A > &	dst
	)

Normalizes histogram for 8-bit gray image.

The input and output 8-bit gray images must have the same size.

Note: This function is a C++ wrapper for function SimdNormalizeHistogram.

Parameters

[in]	src	- an input 8-bit gray image.
[out]	dst	- an output 8-bit image with normalized histogram.

◆ Mean()

void uint8_t Mean ( const uint32_t * histogram )

Calculates mean from image histogram.

Parameters

[in] histogram - a pointer to image histogram (array of 256 unsigned 32-bit integre values).

Returns: value of mean for image with given histogram.

◆ OtsuThreshold()

void uint8_t OtsuThreshold ( const uint32_t * histogram )

Calculates Otsu threhsold from image histogram.

Parameters

[in] histogram - a pointer to image histogram (array of 256 unsigned 32-bit integre values).

Returns: value of Otsu threshold for image with given histogram.

Simd Library Documentation.

Functions

Detailed Description

Function Documentation

◆ SimdAbsSecondDerivativeHistogram()

◆ SimdHistogram()

◆ SimdHistogramMasked()

◆ SimdHistogramConditional()

◆ SimdNormalizedColors()

◆ SimdChangeColors()

◆ SimdNormalizeHistogram()

◆ AbsSecondDerivativeHistogram()

◆ Histogram()

◆ HistogramMasked()

◆ HistogramConditional()

◆ ChangeColors()

◆ NormalizeHistogram()

◆ Mean()

◆ OtsuThreshold()