IMAQ BCGLookup VI

LabView NI Vision

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IMAQ BCGLookup VI

Owning Palette: ProcessingInstalled With: NI Vision Development Module

Applies a brightness, contrast, and gamma correction to an image. The correction is performed by computing and applying a lookup table. Brightness, Contrast, and Gamma control the changes made to the transfer function represented by the lookup table.

Examples

IMAQ BCGLookup

BCG Values is a cluster of the brightness, contrast, and gamma values.

	Brightness (default = 128) sets the brightness of the image. This value is used as the x intercept of the transfer function in the lookup table. The neutral value is 128 (no change in the image). A higher value returns a brighter image. A value less than 128 decreases the overall brightness of the image.
	Contrast (default = 45.0) sets the contrast of the image. This control is used as the slope of the transfer function in the lookup table and is expressed in degrees. A slope of 45 degrees is neutral. A higher value returns a more contrasted image. A value smaller than 45 decreases the contrast of the image.
	Gamma (default = 1.0) sets the gamma correction applied to the image. The neutral value is 1. A value greater than 1 gives extended contrast for small pixel values and less contrast for large pixel values. A value smaller than 1 returns an image with less contrast for small pixel values and extended contrast for large pixel values.

Image Src is a reference to the source image.

Image Mask is an 8-bit image that specifies the region of the small image that will be copied. Only those pixels in the Image Src (Small) image that correspond to an equivalent non-zero pixel in the mask image are copied. All other pixels keep their original values. The entire image is processed if Image Mask is not connected.

Image Dst is a reference to the destination image.

error in (no error) describes the error status before this VI or function runs. The default is no error. If an error occurred before this VI or function runs, the VI or function passes the error in value to error out. This VI or function runs normally only if no error occurred before this VI or function runs. If an error occurs while this VI or function runs, it runs normally and sets its own error status in error out. Use the Simple Error Handler or General Error Handler VIs to display the description of the error code. Use error in and error out to check errors and to specify execution order by wiring error out from one node to error in of the next node.

	status is TRUE (X) if an error occurred before this VI or function ran or FALSE (checkmark) to indicate a warning or that no error occurred before this VI or function ran. The default is FALSE.
	code is the error or warning code. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code.
	source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.

Image Dst Out is a reference to the destination image. If Image Dst is connected, Image Dst Out is the same as Image Dst. Otherwise, Image Dst Out refers to the image referenced by Image Src.

error out contains error information. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information. Otherwise, it describes the error status that this VI or function produces. Right-click the error out indicator on the front panel and select Explain Error from the shortcut menu for more information about the error.

	status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred.
	code is the error or warning code. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code.
	source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.

Examples

Refer to the following for an example that uses this VI.

LabVIEW\examples\Vision\2. Functions\Grayscale Processing\BCG Lookup Example.vi

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