Sobel Statistic

Getting of statistic related with Sobel filters. More...

Functions
SIMD_API void	SimdSobelDxAbsSum (const uint8_t *src, size_t stride, size_t width, size_t height, uint64_t *sum)
	Calculates the sum of absolute horizontal Sobel derivatives. More...
SIMD_API void	SimdSobelDyAbsSum (const uint8_t *src, size_t stride, size_t width, size_t height, uint64_t *sum)
	Calculates the sum of absolute vertical Sobel derivatives. More...
template<template< class > class A>
SIMD_INLINE void	SobelDxAbsSum (const View< A > &src, uint64_t &sum)
	Calculates sum of absolute value of Sobel's filter along x axis. More...
template<template< class > class A>
SIMD_INLINE void	SobelDyAbsSum (const View< A > &src, uint64_t &sum)
	Calculates sum of absolute value of Sobel's filter along y axis. More...

Detailed Description

Getting of statistic related with Sobel filters.

Function Documentation

SimdSobelDxAbsSum()

void SimdSobelDxAbsSum	(	const uint8_t *	src,
		size_t	stride,
		size_t	width,
		size_t	height,
		uint64_t *	sum
	)

Calculates the sum of absolute horizontal Sobel derivatives.

Input image must have 8-bit gray format, and width must be greater than 1. At image borders the nearest valid source row or column is reused. The output sum is initialized to zero inside the function before accumulation.

For every point:

x0 = Max(x - 1, 0); x2 = Min(x + 1, width - 1);
y0 = Max(y - 1, 0); y2 = Min(y + 1, height - 1);
sum += Abs((src[x2, y0] + 2*src[x2, y] + src[x2, y2]) -
           (src[x0, y0] + 2*src[x0, y] + src[x0, y2]));

Note

This function has a C++ wrappers: Simd::SobelDxAbsSum(const View<A>& src, uint64_t & sum).

Parameters

[in]	src	- a pointer to pixels data of the input image.
[in]	stride	- a row size of the input image in bytes.
[in]	width	- an image width.
[in]	height	- an image height.
[out]	sum	- a pointer to unsigned 64-bit integer value with result sum.

SimdSobelDyAbsSum()

void SimdSobelDyAbsSum	(	const uint8_t *	src,
		size_t	stride,
		size_t	width,
		size_t	height,
		uint64_t *	sum
	)

Calculates the sum of absolute vertical Sobel derivatives.

Input image must have 8-bit gray format, and width must be greater than 1. At image borders the nearest valid source row or column is reused. The output sum is initialized to zero inside the function before accumulation.

For every point:

x0 = Max(x - 1, 0); x2 = Min(x + 1, width - 1);
y0 = Max(y - 1, 0); y2 = Min(y + 1, height - 1);
sum += Abs((src[x0, y2] + 2*src[x, y2] + src[x2, y2]) -
           (src[x0, y0] + 2*src[x, y0] + src[x2, y0]));

Note

This function has a C++ wrappers: Simd::SobelDyAbsSum(const View<A>& src, uint64_t & sum).

Parameters

[in]	src	- a pointer to pixels data of the input image.
[in]	stride	- a row size of the input image in bytes.
[in]	width	- an image width.
[in]	height	- an image height.
[out]	sum	- a pointer to unsigned 64-bit integer value with result sum.

SobelDxAbsSum()

void SobelDxAbsSum	(	const View< A > &	src,
		uint64_t &	sum
	)

Calculates sum of absolute value of Sobel's filter along x axis.

Input image must have 8-bit gray format.

For every point:

sum += abs((src[x+1,y-1] + 2*src[x+1, y] + src[x+1, y+1]) - (src[x-1,y-1] + 2*src[x-1, y] + src[x-1, y+1]));

Note

This function is a C++ wrapper for function SimdSobelDxAbsSum.

Parameters

[in]	src	- an input image.
[out]	sum	- an unsigned 64-bit integer value with result sum.

SobelDyAbsSum()

void SobelDyAbsSum	(	const View< A > &	src,
		uint64_t &	sum
	)

Calculates sum of absolute value of Sobel's filter along y axis.

Input image must have 8-bit gray format.

For every point:

sum += abs((src[x-1,y+1] + 2*src[x, y+1] + src[x+1, y+1]) - (src[x-1,y-1] + 2*src[x, y-1] + src[x+1, y-1]));

Note

This function is a C++ wrapper for function SimdSobelDyAbsSum.

Parameters

[in]	src	- an input image.
[out]	sum	- an unsigned 64-bit integer value with result sum.