IG_IP_gaussian_blur

---

Group: Image Processing

Declaration:

AT_ERRCOUNT ACCUAPI IG_IP_gaussian_blur (HIGEAR hIGear,  

	const LPAT_RECT			lpRect,  

	const double			dblRadius  

	); 

Arguments:

hIGear	HIGEAR handle of image
lpRect	Far pointer to AT_RECT struct specifying a portion of the image to be affected. NULL means entire image. Before ImageGear performs this operation, it will check to see if an internal flag has been set to TRUE to make a mask active for this HIGEAR image. If a mask is active, and a valid pointer to a mask can be found, ImageGear will override the settings passed to this structure in favor of the non-rectangular ROI defined by the mask.
dblRadius	Defines the neighborhood to be considered for each pixel.

Description:

This function smoothes the images using Gaussian transform. It makes images look softer and slightly out of focus. A specific feature of Gaussian Blur is that it removes the high-frequency component from the image, which is not the case for the IG_IP_smooth().

Parameter dblRadius corresponds to the Standard Deviation (Sigma) in Gaussian transform. It can range from 0.1 to 500. Typical values for high-resolution images range from 1.0 to 2.0. Larger values will cause greater softening. On the other hand, smaller values are faster. The width of the area considered for each pixel is approximately 6 * dblRadius.

This function, like other ImageGear Image Processing and Clipboard API calls, takes an AT_RECT structure as an argument, so that you can process a rectangular subregion of an image. However, before ImageGear performs the operation specified by this function, it will check to see if an internal flag has been set to TRUE, indicating that a mask HIGEAR should be used with the image. If the flag is set to TRUE, and a valid pointer to a mask image has been assigned, ImageGear will override the settings passed to the AT_RECT structure and use the non-rectangular ROI defined by the mask HIGEAR. To create a non-rectangular region of interest, call IG_IP_NR_ROI_to_HIGEAR_mask().

Bits Per Pixel: 8-bit gray level, 8i, 9-16-bit gray level, 24, and 32

Return Value:

Returns the number of ImageGear errors that occurred during this function call.

Example:

HIGEAR hIGear;  

/* Blur whole image, radius = 2.0 */ 

nErrCount =IG_IP_gaussian_blur ( hIGear, NULL, 2.0 );  

Sample: IMG_PROC