ZXing-C++

ZXing-C++ ("zebra crossing") is an open-source, multi-format linear/matrix barcode image processing library implemented in C++.

It was originally ported from the Java ZXing Library but has been developed further and now includes many improvements in terms of runtime and detection performance. It can both read and write barcodes in a number of formats.

Features

Written in pure C++17 (/C++20), no third-party dependencies (for the library itself)
Thread safe
Wrappers/Bindings for:
- Android
- C
- iOS
- Kotlin/Native
- .NET
- Python
- Rust
- WebAssembly
- WinRT
- Flutter (external project)

Supported Formats

Linear product	Linear industrial	Matrix
UPC-A	Code 39	QR Code
UPC-E	Code 93	Micro QR Code
EAN-8	Code 128	rMQR Code
EAN-13	Codabar	Aztec
DataBar	DataBar Expanded	DataMatrix
	DX Film Edge	PDF417
	ITF	MaxiCode (partial)

[Note:]

DataBar used to be called RSS.
DataBar, DX Film Edge, MaxiCode, Micro QR Code and rMQR Code are not supported for writing.
Building with C++20 (see CMakeLists.txt) changes the behaviour of the library: it then supports multi-symbol and position independent detection for DataMatrix. This comes at a noticable performace cost. C++20 is enabled by default for the Android, iOS, Python and WASM wrappers.

Getting Started

To read barcodes:

Load your image into memory (3rd-party library required).
Call ReadBarcodes() from ReadBarcode.h, the simplest API to get a list of Barcode objects.

A very simple example looks like this:

#include "ZXing/ReadBarcode.h"
#include <iostream>

int main(int argc, char** argv)
{
    int width, height;
    unsigned char* data;
    // load your image data from somewhere. ImageFormat::Lum assumes grey scale image data.

    auto image = ZXing::ImageView(data, width, height, ZXing::ImageFormat::Lum);
    auto options = ZXing::ReaderOptions().setFormats(ZXing::BarcodeFormat::Any);
    auto barcodes = ZXing::ReadBarcodes(image, options);

    for (const auto& b : barcodes)
        std::cout << ZXing::ToString(b.format()) << ": " << b.text() << "\n";

    return 0;
}

To see the full capability of the API, have a look at ZXingReader.cpp.

[Note: At least C++17 is reqired on the client side to use the API.]

To write barcodes:

Create a MultiFormatWriter instance with the format you want to generate. Set encoding and margins if needed.
Call encode() with text content and the image size. This returns a BitMatrix which is a binary image of the barcode where true == visual black and false == visual white.
Convert the bit matrix to your native image format. See also the ToMatrix<T>(BitMatrix&) helper function.

As an example, have a look at ZXingWriter.cpp.

Web Demos

[Note: those live demos are not necessarily fully up-to-date at all times.]

Build Instructions

These are the generic instructions to build the library on Windows/macOS/Linux. For details on how to build the individual wrappers, follow the links above.

Make sure CMake version 3.15 or newer is installed.
Make sure a C++17 compliant compiler is installed (minimum VS 2019 16.8 / gcc 7 / clang 5).
See the cmake ZXING_... options to enable the testing code, python wrapper, etc.

git clone https://github.com/zxing-cpp/zxing-cpp.git --recursive --single-branch --depth 1
cmake -S zxing-cpp -B zxing-cpp.release -DCMAKE_BUILD_TYPE=Release
cmake --build zxing-cpp.release -j8 --config Release

[Note: binary packages are available for/as vcpkg, conan, mingw and a bunch of linux distributions.]

ISNing/zxing-cpp