Blob analysis. More...

Collaboration diagram for Blob:

Data Structures
struct	sb_t_blob_par
	Defines the parameters for blob analysis. More...

struct	sb_t_blobs_info
	Defines the information about the blob analysis. More...

struct	sb_t_blob
	Defines a blob. More...

struct	sb_t_blobs
	Defines a blobs list. More...

Enumerations
enum	sb_t_pixel_connection { SB_PIXEL_CONNECTION_4 = 0 , SB_PIXEL_CONNECTION_8 }
	Defines the pixel connection. More...

enum	sb_t_blob_distance_mode { SB_BLOB_DISTANCE_MODE_BOUNDING_BOX = 0 , SB_BLOB_DISTANCE_MODE_CONTOUR }
	Enumerates the algorithm for calculating the distance between blobs. More...

enum	sb_t_blob_deleted { SB_BLOB_OK = 0 , SB_BLOB_DELETED_BEFORE_MERGE , SB_BLOB_DELETED_AFTER_MERGE }
	Defines the deleted blob. More...

Functions
sb_t_err	sb_blobs_create (sb_t_blobs **const blobs)
	Creates the blobs structure. More...

sb_t_err	sb_blob_init_par (sb_t_blob_par *const par)
	Initializes the fields of the structure. More...

sb_t_err	sb_blob_format_par (const sb_t_blob_par const par, char const str, int str_size)
	Formats the blob analysis parameters structure. More...

sb_t_err	sb_blobs_detection (sb_t_blobs *const blobs, const sb_t_image const image, const sb_t_roi const roi, const sb_t_blob_par const par, sb_t_image_circularity_type circularity_type)
	Blob analysis. More...

sb_t_err	sb_blob_intersect (const sb_t_blob const blob1, const sb_t_blob const blob2, int extract_blob_seg, sb_t_blob **const res)
	Blob intersection. More...

sb_t_err	sb_blobs_plot_roi (const sb_t_blobs const blobs, sb_t_roi const roi, unsigned char gl)
	Prints the blobs on the roi. More...

sb_t_err	sb_blob_plot_roi (const sb_t_blob const blob, sb_t_roi const roi, unsigned char gl)
	Prints the blob on the roi. More...

sb_t_err	sb_blobs_clone (sb_t_blobs *const dst, const sb_t_blobs const src)
	Blobs structure clone. More...

sb_t_err	sb_blobs_destroy (sb_t_blobs **const blobs)
	Destroys the blobs structure. More...

sb_t_err	sb_blob_destroy (sb_t_blob *const blob)
	Destroys the blob. More...

sb_t_err	sb_blob_copy (sb_t_blob const dst, const sb_t_blob const src)
	Blob copy. More...

Detailed Description

Blob analysis.

Enumeration Type Documentation

◆ sb_t_blob_deleted

enum sb_t_blob_deleted

Defines the deleted blob.

The values are 32 bits both for 32 and 64 bits library version.

Enumerator
SB_BLOB_OK	Blob is not deleted.
SB_BLOB_DELETED_BEFORE_MERGE	Blob is deleted before merge.
SB_BLOB_DELETED_AFTER_MERGE	Blob is deleted after merge.

Definition at line 8640 of file sb.h.

◆ sb_t_blob_distance_mode

enum sb_t_blob_distance_mode

Enumerates the algorithm for calculating the distance between blobs.

In the case of irregular or rotated shapes the distance based on the contour and that based on the bounding box give very different results. In the figure below, the blobs are shown in red and their bounding boxes in green. The difference between the two types of measurement is clearly seen. In the case on the right the bounding boxes intersect so their distance is zero while based on the boundaries the blobs are at a certain distance.

Blobs distance

Enumerator

SB_BLOB_DISTANCE_MODE_BOUNDING_BOX

The distance between blobs is calculated using the unrotated bounding box.

SB_BLOB_DISTANCE_MODE_CONTOUR

The distance between blobs is calculated using the contour.

It is possible to select this mode only if the parameter sb_t_blob_par::blob_contour is set to 1.

Definition at line 8546 of file sb.h.

◆ sb_t_pixel_connection

enum sb_t_pixel_connection

Defines the pixel connection.

The values are 32 bits both for 32 and 64 bits library version.

Enumerator

SB_PIXEL_CONNECTION_4

4 connection.

4-connected pixels are neighbors to every pixel that touches one of their edges. These pixels are connected horizontally and vertically. In terms of pixel coordinates, every pixel that has the coordinates (x+1,y), (x-1,y), (x,y+1), (x,y-1) is connected to the pixel at (x,y).

SB_PIXEL_CONNECTION_8

8 connection. 8-connected pixels are neighbors to every pixel that touches one of their edges or corners. These pixels are connected horizontally, vertically, and diagonally. In addition to 4-connected pixels, each pixel with coordinates (x+1,y), (x+1,y+1), (x,y+1), (x-1,y+1) (x-1,y), (x-1,y-1), (x,y-1), (x+1,y-1) is connected to the pixel at (x,y).

Definition at line 8514 of file sb.h.

Function Documentation

◆ sb_blob_copy()

sb_t_err sb_blob_copy	(	sb_t_blob *const	dst,
		const sb_t_blob *const	src
	)

Blob copy.

The function creates a copy of the blob src into the blob dst.

Parameters

[out]	dst	Destination blob.
[in]	src	Source blob.

Returns: If successful, returns SB_ERR_NONE. Otherwise, it returns an error code sb_t_err.

◆ sb_blob_destroy()

sb_t_err sb_blob_destroy ( sb_t_blob *const blob )

Destroys the blob.

The function resets the structure.

Parameters

blob	[in,out] pointer to the blob

Returns: If successful, returns SB_ERR_NONE. Otherwise, it returns an error code sb_t_err.*

◆ sb_blob_format_par()

sb_t_err sb_blob_format_par	(	const sb_t_blob_par *const	par,
		char *const	str,
		int	str_size
	)

Formats the blob analysis parameters structure.

Interprets the contents of par and converts it to a C-string containing a human-readable version of the corresponding structure.

Parameters

[in]	par	Pointer to the blob analysis parameters structure.
[out]	str	Pointer to the string. On successful return, this parameter will be filled with a human-readable version of the blob analysis parameters structure.
[in]	str_size	Number of bytes of the string str.

Returns: If successful, returns SB_ERR_NONE. Otherwise, it returns an error code sb_t_err.

◆ sb_blob_init_par()

sb_t_err sb_blob_init_par ( sb_t_blob_par *const par )

Initializes the fields of the structure.

Parameters

[out] par Pointer to the blob analysis parameters structure.

Returns: If successful, returns SB_ERR_NONE. Otherwise, it returns an error code sb_t_err.

◆ sb_blob_intersect()

sb_t_err sb_blob_intersect	(	const sb_t_blob *const	blob1,
		const sb_t_blob *const	blob2,
		int	extract_blob_seg,
		sb_t_blob **const	res
	)

Blob intersection.

The function extract the blob that represents the intersection of the input blobs.

Parameters

[in]	blob1	First blob.
[in]	blob2	Second blob.
[in]	extract_blob_seg	Enables the extraction of the rle.
[out]	res	Pointer to the result blob (null if no intersection is found).

Returns: If successful, returns SB_ERR_NONE. Otherwise, it returns an error code sb_t_err.

◆ sb_blob_plot_roi()

sb_t_err sb_blob_plot_roi	(	const sb_t_blob *const	blob,
		sb_t_roi *const	roi,
		unsigned char	gl
	)

Prints the blob on the roi.

The function print the blob on the provided roi.
The function updates the sb_t_roi::bounding_box parameter of the roi.

Parameters

[in]	blob	Pointer of the blob.
[in]	roi	Pointer to the ROI.
[in]	gl	Gray level to be set.

Returns: If successful, returns SB_ERR_NONE. Otherwise, it returns an error code sb_t_err.

◆ sb_blobs_clone()

sb_t_err sb_blobs_clone	(	sb_t_blobs **const	dst,
		const sb_t_blobs *const	src
	)

Blobs structure clone.

The function creates a copy of the blobs src into the blobs dst.

Parameters

[out]	dst	Destination blobs.
[in]	src	Source blobs.

Returns: If successful, returns SB_ERR_NONE. Otherwise, it returns an error code sb_t_err.

◆ sb_blobs_create()

sb_t_err sb_blobs_create ( sb_t_blobs **const blobs )

Creates the blobs structure.

Parameters

[out] blobs Pointer to the blob structure. On successful return, this parameter will be updated with the pointer of the blobs structure.

Returns: If successful, returns SB_ERR_NONE. Otherwise, it returns an error code sb_t_err.

◆ sb_blobs_destroy()

sb_t_err sb_blobs_destroy ( sb_t_blobs **const blobs )

Destroys the blobs structure.

Parameters

[in,out] blobs pointer to the blobs structure. It is set to NULL.

Returns: If successful, returns SB_ERR_NONE. Otherwise, it returns an error code sb_t_err.

See also: sb_blobs_detection

◆ sb_blobs_detection()

sb_t_err sb_blobs_detection	(	sb_t_blobs **const	blobs,
		const sb_t_image *const	image,
		const sb_t_roi *const	roi,
		const sb_t_blob_par *const	par,
		sb_t_image_circularity_type	circularity_type
	)

Blob analysis.

The function search for the blobs according to the values in the parameters structure.

Parameters

[out]	blobs	List of the blobs ordered by area descending. On successful return, this parameter will be updated with the pointer of the blobs structure.
[in]	image	Image on which to find the blobs. The format must be SB_IMAGE_FORMAT_BW.
[in]	roi	ROI of the image where to search the blobs. The ROi may be both compress and uncompress. In case it is uncompress the bounding box must be defined.
[in]	par	Pointer to the structure of the blob analysis parameters.
[in]	circularity_type	Circularity property of the image If the image is circular, the function manages the blobs that are divided between the beginning and the end of the image. In this case only one blob is returned which can be either in the initial or final part of the image so that the center of the blob falls within the image, furthermore the coordinates of the contour points and the rle encoding can have negative coordinates or greater than img_width_circular. Only SB_IMAGE_CIRCULARITY_TYPE_HORIZONTAL is managed.

Returns: If successful, returns SB_ERR_NONE. Otherwise, it returns an error code sb_t_err.

See also: sb_blobs_destroy;

◆ sb_blobs_plot_roi()

sb_t_err sb_blobs_plot_roi	(	const sb_t_blobs *const	blobs,
		sb_t_roi *const	roi,
		unsigned char	gl
	)

Prints the blobs on the roi.

The function print the blobs on the provided roi.
The function updates the sb_t_roi::bounding_box parameter of the roi.

Parameters

[in]	blobs	Pointer of the blobs.
[in]	roi	Pointer to the ROI.
[in]	gl	Gray level to be set.

Returns: If successful, returns SB_ERR_NONE. Otherwise, it returns an error code sb_t_err.

Data Structures

Enumerations

Functions

Detailed Description

Enumeration Type Documentation

◆ sb_t_blob_deleted

◆ sb_t_blob_distance_mode

◆ sb_t_pixel_connection

Function Documentation

◆ sb_blob_copy()

◆ sb_blob_destroy()

◆ sb_blob_format_par()

◆ sb_blob_init_par()

◆ sb_blob_intersect()

◆ sb_blob_plot_roi()

◆ sb_blobs_clone()

◆ sb_blobs_create()

◆ sb_blobs_destroy()

◆ sb_blobs_detection()

◆ sb_blobs_plot_roi()