pdf417barcode.cpp

/*
    SPDX-FileCopyrightText: 2021 Volker Krause <[email protected]>
 
    SPDX-License-Identifier: MIT
*/
 
#include "pdf417barcode.h"
#include "zxingutil_p.h"
 
#include <ZXing/BitMatrix.h>
#include <ZXing/MultiFormatWriter.h>
 
#include <stdexcept>
 
using namespace Prison;
 
Pdf417Barcode::Pdf417Barcode()
    : AbstractBarcode(TwoDimensions)
{
}
 
QImage Pdf417Barcode::paintImage(const QSizeF &size)
{
    Q_UNUSED(size);
 
    std::wstring input;
    const bool isBinary = data().isEmpty();
    if (!isBinary) {
        input = data().toStdWString();
    } else {
        const auto b = byteArrayData();
        input.reserve(b.size());
        // ensure we explicitly copy unsigned bytes here, ie. each byte ends up in the least significant byte of
        // the std::wstring. If we end up converting to a signed value inbetween, values > 127 end up negative and
        // will be wrongly represented in the std::wstring
        for (uint8_t c : b) {
            input.push_back(c);
        }
    }
 
    try {
        ZXing::MultiFormatWriter writer(ZXing::BarcodeFormat::PDF417);
        // ISO/IEC 15438:2006(E) §5.8.3 Quiet Zone
        writer.setMargin(2);
        if (isBinary) {
            writer.setEncoding(ZXing::CharacterSet::BINARY);
        }
        // aspect ratio 4 is hard-coded in ZXing
        const auto matrix = writer.encode(input, 4, 1);
        return ZXingUtil::toImage(matrix, foregroundColor(), backgroundColor());
    } catch (const std::invalid_argument &e) {
    }; // input too large
    return {};
}