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RecognizeBarcode

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Module: Barcodes

Extracts information from a barcode located on the input image at a given position.

Applications

Most often used after a barcode detection filter.
Name Type Range Description
Input value
 inImage Image Input image
Input value
 inBarcodePosition Rectangle2D Position of the input image in which the barcode is located
Input value
 inBarcodePositionAlignment CoordinateSystem2D* Adjusts the barcode rectangle to the position of the inspected object
Input value
 inBarcodeParams BarcodeParams Specification of barcode that can be read
Input value
 inScanCount Integer 1 - Number of parallel scans run until first successful read
Input value
 inScanWidth Integer 1 - Width of the single scan
Input value
 inMinEdgeStrength Real 0.0 - Minimal strength of an extracted edge
Output value
 outBarcode Barcode? Decoded barcode or nothing if all of the scans failed
Output value
 outAlignedBarcodePosition Rectangle2D
Diagnostic input
 diagScheduledScanSegments Segment2DArray Scheduled scan segments

Hints

  • Connect inImage with the output of your image acquisition filter.
  • Select inBarcodeParams.Format according to the type of codes you want to read. If you choose the wrong format, the codes will not be recognized. Setting its value to Auto can increase the computation time considerably. Furthermore, the Auto value causes detection of UPC-A codes as EAN-13 codes.

Examples

Description of usage of this filter can be found in examples and tutorial: Barcodes (Pharmacode).

Rotated barcode.

Low quality barcode printed on plastic foil.

Barcode on package wrapped in plastic foil.

Barcode on blurry image.

Barcode on standard 330ml can.

Barcode on reflective and wrapped surface.

EAN-13 with add-on 2 used to indicate a book edition.

EAN-13 with add-on 5 to give a suggestion for the price.

Remarks

Minimal bar width requirement

To provide precise detection of the barcode width of the thinnest bar should be at least 1.5 pixels.

Depending on the barcode format guard or start/end code patterns must be readable.

Pharmacode usage

The pharmacode barcode type can be read correctly in both directions. To get results from both directions use a Pharmacode and PharmacodeInversed barcode types.

Before decoding a Pharmacode the code orientation angle is normalized to a range from -45° to 135° what makes the code decoding more stable

Results of reading using a different Pharmacode directions: Pharmacode = 23 and PharmacodeInversed = 16.

Using a relative coordinate systems

Read more about Local Coordinate Systems in Machine Vision Guide: Local Coordinate Systems.

Complexity Level

This filter is available on Advanced Complexity Level.

See Also

  • DecodeBarcode – Translates an array of bar widths to sequence of digits or text in accordance to the selected barcode standard.