基于C#实现照片条形码识别

一、技术选型对比

库名称	支持格式	识别速度	准确率	开源协议
ZXing.NET	QR/Code128/EAN13等30+格式	中等	高	MIT
ZBar	QR/Code128等主流格式	快	极高	LGPL
TencentOCR	通用条码+文字识别	慢	极高	闭源

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二、核心实现方案（ZXing.NET）

1. 环境配置

Install-Package ZXing.Net
Install-Package ZXing.Net.Bindings.SkiaSharp  # 图像处理增强

2. 基础识别代码

using ZXing;
using ZXing.Common;
using SkiaSharp;

public class BarcodeScanner
{
    public string Scan(string imagePath)
    {
        using var bitmap = SKBitmap.Decode(imagePath);
        var luminanceSource = new SKBitmapLuminanceSource(bitmap);
        
        var reader = new BarcodeReader
        {
            AutoRotate = true,
            TryHarder = true,
            Options = new DecodingOptions
            {
                PossibleFormats = new[] { BarcodeFormat.CODE_128, BarcodeFormat.EAN_13 },
                CharacterSet = "UTF-8",
                PureBarcode = false
            }
        };

        var result = reader.Decode(luminanceSource);
        return result?.Text ?? "未识别到条码";
    }
}

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三、图像预处理优化

1. 灰度化与二值化

public static SKBitmap Preprocess(SKBitmap src)
{
    var dst = new SKBitmap(src.Width, src.Height);
    using var canvas = new SKCanvas(dst);
    
    // 转换为灰度图
    canvas.DrawBitmap(src, 0, 0, new SKPaint
    {
        ColorFilter = SKColorFilter.CreateColorMatrix(new float[]
        {
            0.299f, 0.587f, 0.114f, 0, 0,
            0.299f, 0.587f, 0.114f, 0, 0,
            0.299f, 0.587f, 0.114f, 0, 0,
            0,      0,      0,      1, 0
        })
    });

    // 自适应阈值二值化
    var threshold = new AdaptiveThreshold(0.5f, 5);
    canvas.DrawBitmap(dst, 0, 0, threshold);

    return dst;
}

2. 图像增强

public static SKBitmap Enhance(SKBitmap src)
{
    using var filter = new SKImageFilter.Shadow(SKRect.MakeXYWH(0,0,0,0), 3, 3, 0.5f);
    return SKBitmap.Decode(src.Encode(SKEncodedImageFormat.Png, 100), filter);
}

参考项目 C# 根据照片识别条形码 www.youwenfan.com/contentcng/49545.html

四、高级功能实现

1. 批量识别

public List<string> BatchScan(IEnumerable<string> paths)
{
    var results = new ConcurrentBag<string>();
    Parallel.ForEach(paths, path => 
    {
        var scanner = new BarcodeScanner();
        var result = scanner.Scan(path);
        if (!string.IsNullOrEmpty(result)) 
            results.Add($"{Path.GetFileName(path)}: {result}");
    });
    return results.ToList();
}

2. 实时摄像头扫描

public class CameraScanner : IDisposable
{
    private VideoCaptureDevice _capture;
    private BarcodeReader _reader;

    public event Action<string> CodeDetected;

    public CameraScanner()
    {
        _reader = new BarcodeReader
        {
            AutoRotate = true,
            TryHarder = true
        };
        
        _capture = new VideoCaptureDevice(GetBestDevice());
        _capture.FrameCaptured += OnFrameCaptured;
    }

    private void OnFrameCaptured(object sender, FrameEventArgs e)
    {
        var frame = e.Frame;
        var result = _reader.Decode(frame);
        if (result != null) CodeDetected?.Invoke(result.Text);
    }

    private static VideoCaptureDevice GetBestDevice()
    {
        var devices = CaptureDeviceManager.GetDeviceList(DeviceType.VideoCapture);
        return devices.FirstOrDefault(d => d.MonikerString.Contains("USB")) ?? devices;
    }

    public void Start() => _capture.Start();
    public void Stop() => _capture.Stop();
    public void Dispose() => _capture?.Dispose();
}

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五、常见问题解决方案

1. 中文乱码

// 生成时指定编码
var options = new QrCodeEncodingOptions
{
    CharacterSet = "UTF-8",
    ErrorCorrection = ErrorCorrectionLevel.H
};

2. 低质量图片识别

// 图像预处理流水线
var processed = image
    .Resize(800, 600)       // 统一尺寸
    .Contrast(1.2f)         // 增强对比度
    .Despeckle(3)           // 去噪
    .ToBitmap();

3. 多码同图识别

var results = reader.DecodeMultiple(bitmap);
foreach (var result in results)
{
    Console.WriteLine($"类型：{result.BarcodeFormat}, 内容：{result.Text}");
}

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六、部署建议

1. 硬件要求

   • 最低配置：i5-8代+8GB内存+USB3.0接口
   • 推荐配置：i7-12代+16GB内存+独立显卡

2. 依赖项管理

   <!-- NuGet依赖 -->
   <PackageReference Include="ZXing.Net" Version="0.16.9" />
   <PackageReference Include="SkiaSharp" Version="2.88.4" />
   

3. 安装包制作

   • 使用MSIX打包工具
   • 包含.NET运行时6.0
   • 添加设备驱动签名