IM: Image Analysis

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Image Analysis
[Image Processing]

Detailed Description

: See im_process_ana.h


Functions
int	imAnalyzeFindRegions (const imImage src_image, imImage dst_image, int connect, int touch_border)
void	imAnalyzeMeasureArea (const imImage image, int area)
void	imAnalyzeMeasurePerimArea (const imImage image, float perimarea)
void	imAnalyzeMeasureCentroid (const imImage image, const int area, int region_count, float cx, float cy)
void	imAnalyzeMeasurePrincipalAxis (const imImage image, const int data_area, const float cx, const float cy, const int region_count, float major_slope, float major_length, float minor_slope, float minor_length)
void	imAnalyzeMeasureHoles (const imImage image, int connect, int holes_count, int area, float perim)
void	imAnalyzeMeasurePerimeter (const imImage image, float perim)
void	imProcessPerimeterLine (const imImage src_image, imImage dst_image)
void	imProcessPrune (const imImage src_image, imImage dst_image, int connect, int start_size, int end_size)
void	imProcessFillHoles (const imImage src_image, imImage dst_image, int connect)

Function Documentation

int imAnalyzeFindRegions	(	const imImage *	src_image,
		imImage *	dst_image,
		int	connect,
		int	touch_border
	)

Find white regions in binary image.
Result is IM_USHORT type. Regions can be 4 connected or 8 connected.
Returns the number of regions found. Background is marked as 0.
Regions touching the border are considered only if touch_border=1.

void imAnalyzeMeasureArea	(	const imImage *	image,
		int *	area
	)

Measure the actual area of all regions. Holes are not included.
This is the number of pixels of each region.
Source image is IM_USHORT type (the result of imAnalyzeFindRegions).
data has size the number of regions.

void imAnalyzeMeasurePerimArea	(	const imImage *	image,
		float *	perimarea
	)

Measure the polygonal area limited by the perimeter line of all regions. Holes are not included.
Notice that some regions may have polygonal area zero.
Source image is IM_USHORT type (the result of imAnalyzeFindRegions).
data has size the number of regions.

void imAnalyzeMeasureCentroid	(	const imImage *	image,
		const int *	area,
		int	region_count,
		float *	cx,
		float *	cy
	)

Calculate the centroid position of all regions. Holes are not included.
Source image is IM_USHORT type (the result of imAnalyzeFindRegions).
data has size the number of regions. If area is NULL will be internally calculated.

void imAnalyzeMeasurePrincipalAxis	(	const imImage *	image,
		const int *	data_area,
		const float *	cx,
		const float *	cy,
		const int	region_count,
		float *	major_slope,
		float *	major_length,
		float *	minor_slope,
		float *	minor_length
	)

Calculate the principal major axis slope of all regions.
Source image is IM_USHORT type (the result of imAnalyzeFindRegions).
data has size the number of regions. If area or centroid are NULL will be internally calculated.
Principal (major and minor) axes are defined to be those axes that pass through the centroid, about which the moment of inertia of the region is, respectively maximal or minimal.

void imAnalyzeMeasureHoles	(	const imImage *	image,
		int	connect,
		int *	holes_count,
		int *	area,
		float *	perim
	)

Measure the number and area of holes of all regions.
Source image is IM_USHORT type (the result of imAnalyzeFindRegions).
data has size the number of regions. If some data is NULL it will be not calculated.

void imAnalyzeMeasurePerimeter	(	const imImage *	image,
		float *	perim
	)

Measure the total perimeter of all regions (external and internal).
Source image is IM_USHORT type (the result of imAnalyzeFindRegions).
It uses a half-pixel inter distance for 8 neighboors in a perimeter of a 4 connected region.
This function can also be used to measure line lenght.
data has size the number of regions.

void imProcessPerimeterLine	(	const imImage *	src_image,
		imImage *	dst_image
	)

Isolates the perimeter line of gray integer images. Background is defined as being black (0).
It just checks if at least one of the 4 connected neighboors is non zero. Image borders are extended with zeros.

void imProcessPrune	(	const imImage *	src_image,
		imImage *	dst_image,
		int	connect,
		int	start_size,
		int	end_size
	)

Eliminates regions that have size outside the given interval.
Source and destiny are a binary images. Regions can be 4 connected or 8 connected.
Can be done in-place. end_size can be zero to ignore big objects.

void imProcessFillHoles	(	const imImage *	src_image,
		imImage *	dst_image,
		int	connect
	)

Fill holes inside white regions.
Source and destiny are a binary images. Regions can be 4 connected or 8 connected.
Can be done in-place.

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IM: Image Analysis

Image Analysis [Image Processing]

Detailed Description

Functions

Function Documentation

Image Analysis
[Image Processing]