Vision Laplace Edge :: QUARC Targets Library

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Vision Laplace Edge

This block is currently a beta version. If you are using this block, we would appreciate any feedback at tech@quanser.com.

Calculates Laplacian of the input image.

Library

QUARC Targets Beta/Image Processing/Open Source Computer Vision

Description

Vision Laplace Edge

The Vision Laplace Edge block calculates Laplacian of the source image by summing second x- and y- derivatives calculated using Sobel operator:

edge_image(x,y) = d2src_image/dx2 + d2src_image/dy2.

In order to use this block, be sure to follow the instructions described on the Vision Capture Image page, and take careful note of the limitations.

Input Ports

src_image

A handle to a source image that uses OpenCV (Open Source Computer Vision) IplImage structure.

Output Ports

edge_image

A single-channel signed 16-bit image that shows Laplacian of the input image.

dst_image

Thresholded destination image in 8-bit binary format.

err

An error signal which is negative in case of invalid memory allocation or usage of invalid parameter values.

Parameters and Dialog Box

Vision Laplace Edge

Input image

Specifies the type of input image to be used for edge detection. The available options are Gray, Blue, Green, and Red. If the input image is a color image, this block either converts it into a grayscale image or splits it into red, green, or blue color plane according to the specified parameter. On the other hand, if the input is a grayscale or binary image, the edge detection algorithm is directly applied to it.

Kernel size

Specifies a kernel size of Sobel operator to be convolved with the input image. For kernel size 3×1 or 1×3, the kernel is defined as

                |0   1  0|
                |1  -4  1| .
                |0   1  0|

Threshold

Specifies a 16-bit signed value for Laplacian thresholding.

Threshold type

Specifies the type of thresholding to be used. The options are BINARY and BINARY_INV. The options are described as follows:

                BINARY:
                dst_image(x,y) = 255, if edge_image(x,y)>Threshold
                                 0, otherwise

                BINARY_INV:
                dst_image(x,y) = 0, if edge_image(x,y)>Threshold
                                 255, otherwise

Sample time

The sample time of the block. A sample time of 0 indicates that the block will be treated as a continuous time block. A positive sample time indicates that the block is a discrete time block with the given sample time. A sample time of -1 indicates that the block inherits its sample time.

Targets

Target Name	Compatible*	Model Referencing	Comments
QUARC Win32 Target	No	No	Not supported.
QUARC Win64 Target	No	No	Not supported.
QUARC Linux Nvidia Target	Yes	Yes
QUARC Linux QBot Platform Target	Yes	Yes
QUARC Linux QCar 2 Target	Yes	Yes
QUARC Linux QDrone 2 Target	Yes	Yes
QUARC Linux Raspberry Pi 3 Target	Yes	Yes
QUARC Linux Raspberry Pi 4 Target	Yes	Yes
QUARC Linux RT ARMv7 Target	Yes	Yes
QUARC Linux x64 Target	Yes	Yes
QUARC Linux DuoVero Target	Yes	Yes
QUARC Linux DuoVero 2016 Target	Yes	Yes
QUARC Linux Verdex Target	Yes	Yes
QUARC QNX x86 Target	No	No	Not supported.
Rapid Simulation (RSIM) Target	No	No	Not supported.
S-Function Target	No	N/A	Old technology. Use model referencing instead.
Normal simulation	Yes	Yes

* Compatible means that the block can be compiled for the target.