Utils

Functions for general purpose and supporting your app. More...

Functions
VL_SDK_API char *VL_CALLINGCONVENTION	vlSDKUtil_get (const char *uri, unsigned long *size, const char *options=0)
	Retrieves a file and its data from a given URI. More...
VL_SDK_API bool VL_CALLINGCONVENTION	vlSDKUtil_set (const char *uri, const void *data, unsigned long size, const char *options=0)
	Posts or writes data to given URI. More...
VL_SDK_API bool VL_CALLINGCONVENTION	vlSDKUtil_getTempFilename (const char *prefName, char *newName, unsigned int maxSize)
	Generate a temporary file URI. More...
VL_SDK_API char *VL_CALLINGCONVENTION	vlSDKUtil_getCameraPositionsFromGeometry (const char *geometryJson, unsigned long *size)
	Transforms a workspace geometry into a list of points. More...
VL_SDK_API char *VL_CALLINGCONVENTION	vlSDKUtil_getCameraTransformsFromWorkspaceDefinition (const char *workspaceJson, unsigned long *size)
	Transforms a workspace definition into a list of poses. More...
VL_SDK_API double VL_CALLINGCONVENTION	vlSDKUtil_getPosterQuality (vlImageWrapper_t *imageWrapper)
	Estimates the quality of a given image as a PosterTracker reference. More...

Detailed Description

Functions for general purpose and supporting your app.

Functions allowing to support your implementation with the visionlibSDK.

Function Documentation

vlSDKUtil_get()

VL_SDK_API char* VL_CALLINGCONVENTION vlSDKUtil_get	(	const char *	uri,
		unsigned long *	size,
		const char *	options = 0
	)

Retrieves a file and its data from a given URI.

This function tries to retrieve a file synchronously from a given source URI. An AbstractApplication instance has to be created before calling this function. The URI can point to a file on disk (file:///path) or even to a file on a web server (http://192.0.0.1/file). VisionLib schemes (e.g. project_dir:filename) and custom schemes are also supported.

Parameters

uri	A zero terminated string containing the URI.
size	A pointer to an unsigned long integer, which will be used to store the size of the retrieved file.
options	An optional pointer (can be NULL), which describes some options for download (not used yet).

Returns

A valid pointer to the memory which MUST be freed using vlReleaseBinaryBuffer(), on success. Returns NULL if an error occurred.

vlSDKUtil_getCameraPositionsFromGeometry()

VL_SDK_API char* VL_CALLINGCONVENTION vlSDKUtil_getCameraPositionsFromGeometry	(	const char *	geometryJson,
		unsigned long *	size
	)

Transforms a workspace geometry into a list of points.

This function parses a workspace defined in json and transforms it into an array of positions (3 float values).

Parameters

geometryJson	A zero terminated string containing the geometry definition as json.
size	A pointer to an unsigned long integer, which will be used to store the size of the retrieved file.

Returns

A valid pointer to the memory which MUST be freed using vlReleaseBinaryBuffer(), on success. Returns NULL if an error occurred.

vlSDKUtil_getCameraTransformsFromWorkspaceDefinition()

VL_SDK_API char* VL_CALLINGCONVENTION vlSDKUtil_getCameraTransformsFromWorkspaceDefinition	(	const char *	workspaceJson,
		unsigned long *	size
	)

Transforms a workspace definition into a list of poses.

This function parses a workspace defined in json and transforms it into an array of camera transformations (7 float values tx, ty, tz, rx, ry, rz, rw).

Parameters

geometryJson	A zero terminated string containing the geometry definition as json.
size	A pointer to an unsigned long integer, which will be used to store the size of the retrieved file.

Returns

A valid pointer to the memory which MUST be freed using vlReleaseBinaryBuffer(), on success. Returns NULL if an error occurred.

vlSDKUtil_getPosterQuality()

VL_SDK_API double VL_CALLINGCONVENTION vlSDKUtil_getPosterQuality

(

vlImageWrapper_t *

imageWrapper

)

Estimates the quality of a given image as a PosterTracker reference.

Parameters

imageWrapper

The image in any image format.

Returns

The quality between 0 (bad) and 1 (good).

vlSDKUtil_getTempFilename()

VL_SDK_API bool VL_CALLINGCONVENTION vlSDKUtil_getTempFilename	(	const char *	prefName,
		char *	newName,
		unsigned int	maxSize
	)

Generate a temporary file URI.

This function creates a filename that can be written to on the local file system of the device. A hint can be given, which will get incorporated into the filename.

Parameters

prefName	A zero terminated string containing the preferred name, which can also be NULL.
newName	Buffer for storing the filename as zero terminated string.
maxSize	Size of the buffer.

Returns

true, on success; false, otherwise.

vlSDKUtil_set()

VL_SDK_API bool VL_CALLINGCONVENTION vlSDKUtil_set	(	const char *	uri,
		const void *	data,
		unsigned long	size,
		const char *	options = 0
	)

Posts or writes data to given URI.

This function tries to write a file synchronously to a given URI. An AbstractApplication instance has to be created before calling this function. The URI can point to a file on disk (file:///path) or even to a file on a web server (http://192.0.0.1/file). VisionLib schemes (e.g. data_dir:filename) and custom schemes are also supported.

Parameters

uri	A zero terminated string containing the URI.
data	A pointer to the data to be written.
size	Number of bytes to be written.
options	An optional pointer (can be NULL), which describes some options for download (not used yet)

Returns

true, on success; false, otherwise.