Parameter and Result Types

MERLIC supports various parameter and result types when working with MERLIC tools. Tool parameters are represented on the top left of the Tool Board. Tool results are represented on the bottom left of the Tool Board. When parameters or results are visible by default, they are called "Basic Parameters" or "Basic Results". If they can be added manually via the button, they are called "Additional Parameters" or "Additional Results". Also, there are training parameters and results (both "basic" and "additional") at the top and bottom right of the Tool Board. These are needed to train MERLIC tools that have a training mode.

All of the basic, additional, and training parameters and results can be sorted into different types. These types apply to both parameters and results because the result of one tool can become the parameter of another. In the following you can find an overview of all the types of parameters and results:

Alignment Data

Parameters and results of the type "Alignment Data" determine the alignment of an object with respect to a reference object. The alignment data contains the rotation and translation that is required to align the object with its reference.

There are only two MERLIC tools that calculate "Alignment Data": Determine Alignment with Matching and Determine Alignment with Straight Border. However, many other MERLIC tools can use it as input data for further processing.

Calibration Data

Parameters and results of the type "Calibration Data" transfer camera coordinates to world coordinates. It is used to determine possible lens distortions of the device that was used to acquire the image data and its position with respect to the image plane.

There are only two MERLIC tools that calculate "Calibration Data": Calibrate Camera and Determine Pixel Size. However, the tools Rectify Image and Set Calibration Origin as well as the tools of the categories Measuring and Position Determination and the tool Check Presence with Matching can use it as input data for further processing.

Contour

Parameters and results of the type "Contour" mark the outline of an object. Unlike a region or ROI, they are not filled in. Contours indicate where something was found, e.g., the outline of a font or a QR code. The MERLIC tool Evaluate Contours can be used to evaluate contours.

File Path

Parameters of the type "File Path" are a specific type of tuple. Depending on the MERLIC tool, they consist of a tuple with one or more strings that define the name and the path from which a tool reads the information it needs. However, parameters and results of the type "File Path" behave differently to the parameters and results of the type "Tuple". This is because the string represents the path to a directory or a file within a file system and the parameter is set up so that the user can browse for the file via the icon.

Examples for tools that use the parameter of the type "File Path" are Acquire Image from File, Write to File, or Read Text and Numbers with Deep Learning. Depending on which kind of file the tool is requiring, the parameter expects a specific or one of several predefined file formats.

Handle

Parameters and results of the type "Handle" are simple values that are representative of a more complex kind of data structure. For efficiency and data security reasons, not the entire structure but only the handle is passed between the MERLIC tools. Examples for MERLIC tools that use handles are Write to Socket or Read from Socket.

Image

Parameters and results of the type "Image" consist of a pixel matrix with a defined height and width and additional color channels. The number of channels varies from image to image.

MERLIC supports images with the following pixel types:

Pixel Type

Description

Value Range

byte

1 byte per pixel, unsigned

0 ... 255

int1

1 byte per pixel, signed

−128 ... 127

uint2

2 bytes per pixel, unsigned

0 ... 65535 (216 −1)

int2

2 bytes per pixel, signed

−32 768 (−215) ... 32 767 (215 - 1)

int4

4 bytes per pixel, signed

−2 147 483 648 (−231) ... 2 147 483 647 (231 - 1)

int8

8 bytes per pixel, signed

-9 223 372 036 854 775 808 (−263) ... 9 223 372 036 854 775 807 (263 - 1)

real

4 bytes per pixel, floating point

Precision: 6 significant decimal digits

−3.4e38 to 3.4e38

Most of the provided MERLIC tools require a "byte" image as input. If your input image has a different pixel type, you can use the MERLIC tool Scale Gray Range to 8 Bit to convert it. However, some MERLIC tools work with input images of other pixel types. Also, there are MERLIC tools that create output images of another pixel type, e.g., the tool Convert Disparity to Height Image puts out images of the pixel type "real".

Region

Parameters and results of the type "Region" can be imagined as a mask, i.e., a binary image. A region consists of a set of image points without gray values. It can be described as a set of coordinates in the image plane.

A region does not need to be connected and it may contain holes. Regions can be used, e.g., to mark a location on an image, or to group pixels with the same color value.

Region of Interest (ROI)

Parameters and results of the type "ROI" are a specific type of region that is used to restrict tools to work only on a certain area of an image. Only the image part corresponding to the region remains relevant, which reduces the number of pixels to be processed. The aim is to focus the processing and to save processing time. Consequently, the output of the tools contains only results with respect to these ROIs.

ROIs can be created manually and by using easyTouch and easyTouch+. MERLIC has several tools to create ROIs in different shapes. Find out more in the chapter ROI.

If an ROI was created with a MERLIC tool that is connected to calibration data, the ROI itself will be calibrated.

Tuple

Parameters and results of the type "Tuple" are returned as a list of elements, e.g., numeric values, strings, or Boolean values. As scalars are tuples with only one element, they belong to the type "Tuple".

If a tuple contains multiple elements, only the values of the first elements might be visible at the tool board in the Tool Workspace. For information about how to inspect all tuple values, see the topic Data Connectors.