Raspberry Pi Barcode Reader with DBR 5.2
Dynamsoft finally released Barcode Reader SDK v5.2 for Raspberry Pi. It is time to make an update. In this post, I will show you how to install the SDK, as well as how to write a simple Raspberry Pi barcode app using C/C++ and Python.
Installation
Tarball
Download dbr-rpi-5.2.0.tar.gz.
Extract the package:
tar -xvf dbr-rpi-5.2.0.tar.gz
Create a symlink for libDynamsoftBarcodeReader.so:
sudo ln –s <Your PATH>/libDynamsoftBarcodeReader.so /usr/lib/libDynamsoftBarcodeReader.so
Command line tool
Add public key:
wget -O - http://labs.dynamsoft.com/debian/conf/dbr.gpg.key | sudo apt-key add -
Add source to /etc/apt/sources.list:
deb http://labs.dynamsoft.com/debian/ dbr main non-free
Install Dynamsoft Barcode Reader:
sudo apt-get update && install dbr
Walkthrough of Raspberry Pi Barcode SDK
Getting started with C/C++ sample
Compile the built-in sample code:
cd <Package-root>/samples/c/
make
./BarcodeReaderDemo ../../images/Codabar.jpg
Barcode extension for Python 2 and Python 3
Create setup.py:
from distutils.core import setup, Extension
import os, numpy
numpy_include = os.path.join(os.path.dirname(numpy.__file__), "core", "include", "numpy")
print(numpy_include)
module_dbr = Extension('dbr',
sources = ['dbr.c'],
include_dirs=[numpy_include, '<Path- DynamsoftBarcodeReader.h>'],
libraries=['DynamsoftBarcodeReader'])
setup (name = 'DynamsoftBarcodeReader',
version = '5.2',
description = 'Python barcode extension',
ext_modules = [module_dbr])
Here I don’t explain dbr.c. If you are interested in the source code, please read How to Port C/C++ Barcode Extension to Python 3.
Build and install Python extension:
sudo python setup.py build install
Now we can quickly create a Raspberry Pi barcode app:
import os.path
import dbr
def initLicense(license):
dbr.initLicense(license)
def decodeFile(fileName):
formats = 0x3FF | 0x2000000 | 0x8000000 | 0x4000000 # 1D, QRCODE, PDF417, DataMatrix
results = dbr.decodeFile(fileName, formats)
for result in results:
print("barcode format: " + result[0])
print("barcode value: " + result[1])
def decodeBuffer(image):
formats = 0x3FF | 0x2000000 | 0x8000000 | 0x4000000 # 1D, QRCODE, PDF417, DataMatrix
results = dbr.decodeBuffer(image, formats)
for result in results:
print("barcode format: " + result[0])
print("barcode value: " + result[1])
if __name__ == "__main__":
barcode_image = input("Enter the barcode file: ")
if not os.path.isfile(barcode_image):
print("It is not a valid file.")
else:
initLicense("t0068MgAAAHtCgAPxEdCJN1bsu9n6YfnWDoaW7YZomIZZke2m9KynRnKSqsuQyd7Cdgo6razlb7VU3IFaKeBgg9Rq069Uihc=")
decodeFile(barcode_image)
Create Shell scripts for SDK distribution
If you are a Python developer, you have to build the barcode module yourselves. We can use Shell scripts to automate the process.
Check CPU architectures for ARMv6 and ARMv7:
#!/bin/bash
CPU=$(lscpu)
ARMV6=$(echo $CPU | grep "armv6")
ARMV7=$(echo $CPU | grep "armv7")
if [ -n "${ARMV6}" ]
then
echo "this is armv6"
sudo ln -s $PWD/lib/armv6l/libDynamsoftBarcodeReader.so /usr/lib/libDynamsoftBarcodeReader.so
fi
if [ -n "${ARMV7}" ]
then
echo "this is armv7"
sudo ln -s $PWD/lib/armv7l/libDynamsoftBarcodeReader.so /usr/lib/libDynamsoftBarcodeReader.so
fi
Install essential packages for new environment:
sudo apt-get install python-dev python-pip
sudo pip install numpy
Build and install the Python module:
sudo python ./lib/python/setup.py build install
Remove the Python module:
#!/bin/bash
DBR_LIBRARY=$(python -c "import dbr; print(dbr.__file__)")
sudo rm "$DBR_LIBRARY"
sudo rm /usr/lib/libDynamsoftBarcodeReader.so
