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Read the QR Code (read_qr_code)

Aim

Devise an algorithm that reads QR codes from images.

Input

A set of images with QR Codes captured under different lighting conditions.

Images are stored in the ''read_qr_code'' directory.

Output

A position and a text read from a QR Code. The read text should be drawn in the input image.

Hints

This exercise shows the concept of performing one of the most typical vision problems. It can be solved using a predefined set of filters. In this case, only a single filter is used to determine the code position and to read data from it.

To get images from a directory, EnumerateImages filter should be used. To find the QR Code in an image, use a high-level ReadSingleQRCode filter. DrawStrings_SingleColor filter may be helpful to show the results.

Labeling connections is explained in this article.

Solution (AVS)

  1. Add the EnumerateImages filter to ACQUIRE section to obtain images from a directory. Enter the image directory path to the inDirectory input.

  2. Add the ReadSingleQRCode filter to PROCESS section. Connect the outImage output of the EnumerateImages filter to the inImage input of the ReadSingleQRCode filter.

  3. Add the DrawStrings_SingleColor filter to the project and configure the inputs: inLocations and inColor. Set inSize to 20.

  4. Connect the outQRCode.Text output of the ReadSingleQRCode filter to the inStrings input of the DrawStrings_SingleColor filter.

  5. Add outImage of the DrawStrings_SingleColor filter to a preview window.

Main macrofilter reads data from a QR code and writes result on an input image.