Python Extension: Barcode and QR Code SDK

This project provides a CPython binding to the Dynamsoft C/C++ Barcode Reader SDK v9.x. It demonstrates how to build a Python 1D/2D barcode SDK package for Windows, Linux and macOS from scratch. Beyond desktop PCs, it's also compatible with embedded and IoT devices such as Raspberry Pi and Jetson Nano. You are free to customize the Python API for Dynamsoft Barcode Reader to suit your specific needs.

Note: This project is an unofficial, community-maintained Python wrapper for the Dynamsoft Barcode SDK. For those seeking the most reliable and fully-supported solution, Dynamsoft offers an official Python package. Visit the Dynamsoft Capture Vision Bundle page on PyPI for more details.

About Dynamsoft Capture Vision Bundle

• Get a 30-day FREE trial license to activate the SDK.
• Install the SDK via pip install dynamsoft-capture-vision-bundle.

Comparison Table

Feature	Unofficial Wrapper (Community)	Official Dynamsoft Python Barcode SDK
Support	Community-driven, best effort	Official support from Dynamsoft
Documentation	README only	Comprehensive Online Documentation
API Coverage	Limited	Full API coverage
Feature Updates	May lag behind the official SDK	First to receive new features
Compatibility	Limited testing across environments	Thoroughly tested across all supported environments
OS Support	Windows, Linux, macOS	Windows, Linux, macOS

Supported Python Edition

• Python 3.x

Installation of Dependencies

To show UI, you need to install the OpenCV package:

pip install opencv-python

Command-line Usage

$ scanbarcode <file-name> -l <license-key>

# Show the image with OpenCV
$ scanbarcode <file-name> -u 1 -l <license-key>

How to Build the Python Barcode and QR Code Extension

• Create a source distribution:

  python setup.py sdist

• setuptools:

  python setup_setuptools.py build
  python setup_setuptools.py develop # Copy libraries to barcodeQrSDK folder

• scikit-build:

  python setup.py build
  python setup.py develop # Copy libraries to barcodeQrSDK folder

• Build wheel:

  pip wheel . --verbose
  # Or
  python setup_setuptools.py bdist_wheel
  # Or
  python setup.py bdist_wheel

Quick Start

• Console App

  import barcodeQrSDK
  
  # set license
  barcodeQrSDK.initLicense("LICENSE-KEY")
  
  reader = barcodeQrSDK.createInstance()
  
  results, elapsed_time = reader.decodeFile("IMAGE-FILE")
  for result in results:
      print(result.format)
      print(result.text)
      print(result.x1)
      print(result.y1)
      print(result.x2)
      print(result.y2)
      print(result.x3)
      print(result.y3)
      print(result.x4)
      print(result.y4)

• Video App

  import barcodeQrSDK
  import numpy as np
  import cv2
  import json
  
  g_results = None
  
  def callback(results, elapsed_time):
      global g_results
      g_results = (results, elapsed_time)
  
  def run():
      # set license
      barcodeQrSDK.initLicense("LICENSE-KEY")
  
      # initialize barcode scanner
      scanner = barcodeQrSDK.createInstance()
      params = scanner.getParameters()
      # Convert string to JSON object
      json_obj = json.loads(params)
      # json_obj['ImageParameter']['ExpectedBarcodesCount'] = 999
      params = json.dumps(json_obj)
      ret = scanner.setParameters(params)
      
      scanner.addAsyncListener(callback)
  
      cap = cv2.VideoCapture(0)
      while True:
          ret, image = cap.read()
          if image is not None:
              scanner.decodeMatAsync(image)
              
          if g_results != None:
              print('Elapsed time: ' + str(g_results[1]) + 'ms')
              cv2.putText(image, 'Elapsed time: ' + str(g_results[1]) + 'ms', (10, 30), cv2.FONT_HERSHEY_SIMPLEX, 1, (0, 0, 255), 2)
              for result in g_results[0]:
                  x1 = result.x1
                  y1 = result.y1
                  x2 = result.x2
                  y2 = result.y2
                  x3 = result.x3
                  y3 = result.y3
                  x4 = result.x4
                  y4 = result.y4
                  
                  cv2.drawContours(image, [np.int0([(x1, y1), (x2, y2), (x3, y3), (x4, y4)])], 0, (0, 255, 0), 2)
                  cv2.putText(image, result.text, (x1, y1), cv2.FONT_HERSHEY_SIMPLEX, 1, (0, 255, 0), 2)
  
          cv2.imshow('Barcode QR Code Scanner', image)
          ch = cv2.waitKey(1)
          if ch == 27:
              break
      
      scanner.clearAsyncListener()
  
  if __name__ == '__main__':
      run()

  

Methods

• barcodeQrSDK.initLicense('YOUR-LICENSE-KEY'): Set the global license key for the barcode SDK.

  barcodeQrSDK.initLicense("LICENSE-KEY")

• barcodeQrSDK.createInstance(): Create a new barcode reader instance.

  reader = barcodeQrSDK.createInstance()

• decodeFile(filename): Decode barcodes and QR codes from an image file.

  results, elapsed_time = reader.decodeFile("IMAGE-FILE")

• decodeMat(Mat image): Decode barcodes and QR codes from an OpenCV Mat.

  image = cv2.imread("IMAGE-FILE")
  results = reader.decodeMat(image)
  for result in results:
      print(result.format)
      print(result.text)
      print(result.x1)
      print(result.y1)
      print(result.x2)
      print(result.y2)
      print(result.x3)
      print(result.y3)
      print(result.x4)
      print(result.y4)

• getParameters(): Retrieve the current SDK parameters as a JSON string.

  params = reader.getParameters()

• setParameters(JSON string): Set barcode SDK parameters using a JSON string.

  import json
  json_obj = json.loads(params)
  json_obj['ImageParameter']['DPMCodeReadingModes'][0]['Mode'] = 'DPMCRM_GENERAL'
  json_obj['ImageParameter']['LocalizationModes'][0]['Mode'] = 'LM_STATISTICS_MARKS'
  params = json.dumps(json_obj)
  ret = reader.setParameters(params)

• addAsyncListener(callback function): Register a Python function to receive barcode results asynchronously.

• decodeMatAsync(<opencv mat data>): Asynchronously decode barcodes and QR codes from an OpenCV Mat.

  def callback(results, elapsed_time):
      print(results)
                                                      
  import cv2
  image = cv2.imread("IMAGE-FILE")
  reader.addAsyncListener(callback)
  reader.decodeMatAsync(image)
  sleep(1)

• clearAsyncListener(): Stop the asynchronous listener and clear the registered callback.

• decodeBytes(bytes, width, height, stride, imageformat): Decode barcodes from a raw image byte array.

  import cv2
  image = cv2.imread("IMAGE-FILE")
  results, elapsed_time = scanner.decodeBytes(image.tobytes(), image.shape[1], image.shape[0], image.strides[0], barcodeQrSDK.ImagePixelFormat.IPF_BGR_888)

• decodeBytesAsync: Asynchronously decode image byte arrays.

  def callback(results, elapsed_time):
      print(results)
                                                      
  import cv2
  image = cv2.imread("IMAGE-FILE")
  imagebytes = image.tobytes()
  scanner.decodeBytesAsync(image.tobytes(), image.shape[1], image.shape[0], image.strides[0], barcodeQrSDK.ImagePixelFormat.IPF_BGR_888)
  sleep(1)

Supported Barcode Symbologies

• Linear Barcodes (1D)

  • Code 39 (including Code 39 Extended)
  • Code 93
  • Code 128
  • Codabar
  • Interleaved 2 of 5
  • EAN-8
  • EAN-13
  • UPC-A
  • UPC-E
  • Industrial 2 of 5

• 2D Barcodes:

  • QR Code (including Micro QR Code)
  • Data Matrix
  • PDF417 (including Micro PDF417)
  • Aztec Code
  • MaxiCode (mode 2-5)

• Patch Code

• GS1 Composite Code