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ReadMultipleBarcodes

Basic

Module: Barcodes

Detects and recognizes multiple barcodes on the input image.

Applications

To be used as an easy all-in-one solution for typical barcode reading applications.
Name Type Range Description
Input value
 inImage Image Input image
Input value
 inRoi ShapeRegion* Region of interest
Input value
 inRoiAlignment CoordinateSystem2D* Adjusts the region of interest to the position of the inspected object
Input value
 inBarcodeParams BarcodeParams Specification of barcodes that can be detected
Input value
 inDetectionParams BarcodeDetectionParams Parameters of the barcode detection algorithm
Input value
 inMaxBarcodeCount Integer 1 - Maximum number of barcodes in one image
Output value
 outBarcodes BarcodeArray List of barcodes that have been correctly detected and decoded
Output value
 outBarcodeCandidates Rectangle2DArray Places with high gradient values that are further investigated
Output value
 outAlignedRoi ShapeRegion Input ROI after transformation (in the image coordinates)
Diagnostic input
 diagGradientImage Image Image of gradient directions
Diagnostic input
 diagScheduledScanSegments Segment2DArrayArray Scheduled scan segments

Description

This filter detects barcodes present in the input image and reads their content.

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.
  • If the image resolution is high, set inBarcodeParams.MaxModuleSize accordingly or resize/downsample the input image.

Examples

Two barcodes in a good quality image.

Two barcodes in a blurry image.

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.

Hardware Acceleration

This operation supports automatic parallelization for multicore and multiprocessor systems.

Complexity Level

This filter is available on Basic Complexity Level.

Filter Group

This filter is member of ReadBarcodes filter group.

See Also

  • DecodeBarcode – Translates an array of bar widths to sequence of digits or text in accordance to the selected barcode standard.
  • RecognizeBarcode – Extracts information from a barcode located on the input image at a given position.