F_VN_ReadDataMatrixCodeRoi
Detect and interpret a data matrix code (ECC200) within the provided image. The code should be in the image center.
Can use available TwinCAT Job Tasks for executing parallel code regions.
Syntax
Definition:
FUNCTION F_VN_ReadDataMatrixCodeRoi : HRESULT
VAR_INPUT
ipSrcImage : ITcVnImage;
ipDecodedData : Reference To ITcVnContainer;
fModuleWidth : REAL;
hrPrev : HRESULT;
END_VAR
VAR_OUTPUT
fAngleDeg : REAL;
END_VAR
Inputs
Name | Type | Description |
|---|---|---|
ipSrcImage | Source image (USINT elements, 1 channel) | |
ipDecodedData | Reference To ITcVnContainer | Returns the decoded code (ContainerType_String_SINT) |
fModuleWidth | REAL | Minimum module width of the code in the image (in pixels). Must be at least 3, preferably 5 - 8. |
hrPrev | HRESULT indicating the result of previous operations (If SUCCEEDED(hrPrev) equals false, no operation is executed.) |
Outputs
Name | Type | Description |
|---|---|---|
fAngleDeg | REAL | Returns the clockwise rotation angle in degree |
Further information
The F_VN_ReadDataMatrixCodeRoi function is optimized for the detection of a single Data Matrix code (ECC200) within a defined image area. To do this, the function uses a customized algorithm that requires the code to be centered in the transferred image.
fModuleWidth
The fModuleWidth parameter defines the minimum expected module width of the Data Matrix code to be read in pixels. A module corresponds to a black or white square of the code. If the module size in the image differs more from this, this may result in longer calculation time or no result.
Required License
TC3 Vision Code Reading
System Requirements
Development environment | Target platform | PLC libraries to include |
|---|---|---|
TwinCAT V3.1.4024.59 or later | PC or CX (x64) with min. PL50, e.g. Intel 4-core Atom CPU | Tc3_Vision |