VB.NET 中的 OCR

VB.NET 起始代碼

自動 Ocr

using IronOcr;

string imageText = new IronTesseract().Read(@"images\image.png").Text;

Install-Package IronOcr

IronOCR 的獨特之處在於它能夠自動偵測和讀取掃描不完美的影像和 PDF 文件中的文字。 IronTesseract 類別提供了最簡單的 API。

嘗試其他程式碼範例，以獲得對 C# OCR 操作的更精細控制。

IronOCR 提供了目前已知最先進的 Tesseract 版本，適用於任何平台，速度更快，準確性更高，並且具有原生 DLL 和 API。

支援.NET Framework、Standard、Core、Xamarin 和 Mono 的 Tesseract 3、Tesseract 4 和 Tesseract 5。

## 如何在.NET中進行OCR

安裝 VB .NET庫以對影像或 PDF 檔案進行 OCR 識別
實例化`IronTesseract`以使用直覺的 API
在.NET中使用`Read`方法執行 OCR。
透過存取`Text`屬性來取得 OCR 結果
用一行程式碼執行步驟 2、3 和 4。

Explore the IronTesseract C# OCR How-To Guide

國際語言

using IronOcr;
using System;

var ocrTesseract = new IronTesseract();

ocrTesseract.Language = OcrLanguage.Arabic;

using (var ocrInput = new OcrInput())
{
    ocrInput.LoadImage(@"images\arabic.gif");
    var ocrResult = ocrTesseract.Read(ocrInput);
    Console.WriteLine(ocrResult.Text);
}

// Example with a Custom Trained Font Being used:

var ocrTesseractCustomerLang = new IronTesseract();
ocrTesseractCustomerLang.UseCustomTesseractLanguageFile("custom_tesseract_files/custom.traineddata");
ocrTesseractCustomerLang.AddSecondaryLanguage(OcrLanguage.EnglishBest);

using (var ocrInput = new OcrInput())
{
    ocrInput.LoadPdf(@"images\mixed-lang.pdf");
    var ocrResult = ocrTesseractCustomerLang.Read(ocrInput);
    Console.WriteLine(ocrResult.Text);
}

Install-Package IronOcr

IronOCR語言支持

IronOCR支援 125 種國際語言。除了預設安裝的英文之外，還可以透過NuGet將其他語言套件新增至您的.NET專案中，或從我們的語言頁面下載其他語言套件。

大多數語言都提供快速、標準（建議）和最佳品質三種版本。最佳品質選項可能提供更準確的結果，但處理時間也會更慢。

使用IronOCR探索多種語言的 OCR 功能。

結果對象

using IronOcr;
using IronSoftware.Drawing;

// We can delve deep into OCR results as an object model of
// Pages, Barcodes, Paragraphs, Lines, Words and Characters
// This allows us to explore, export and draw OCR content using other APIs/
var ocrTesseract = new IronTesseract();

ocrTesseract.Configuration.ReadBarCodes = true;

using var ocrInput = new OcrInput();
var pages = new int[] { 1, 2 };
ocrInput.LoadImageFrames("example.tiff", pages);

OcrResult ocrResult = ocrTesseract.Read(ocrInput);
foreach (var page in ocrResult.Pages)
{
    // Page object
    int PageNumber = page.PageNumber;
    string PageText = page.Text;
    int PageWordCount = page.WordCount;
    // null if we dont set Ocr.Configuration.ReadBarCodes = true;
    OcrResult.Barcode[] Barcodes = page.Barcodes;
    AnyBitmap PageImage = page.ToBitmap(ocrInput);
    double PageWidth = page.Width;
    double PageHeight = page.Height;
    double PageRotation = page.Rotation; // angular correction in degrees from OcrInput.Deskew()

    foreach (var paragraph in page.Paragraphs)
    {
        // Pages -> Paragraphs
        int ParagraphNumber = paragraph.ParagraphNumber;
        string ParagraphText = paragraph.Text;
        AnyBitmap ParagraphImage = paragraph.ToBitmap(ocrInput);
        int ParagraphX_location = paragraph.X;
        int ParagraphY_location = paragraph.Y;
        int ParagraphWidth = paragraph.Width;
        int ParagraphHeight = paragraph.Height;
        double ParagraphOcrAccuracy = paragraph.Confidence;
        OcrResult.TextFlow paragrapthText_direction = paragraph.TextDirection;
        foreach (var line in paragraph.Lines)
        {
            // Pages -> Paragraphs -> Lines
            int LineNumber = line.LineNumber;
            string LineText = line.Text;
            AnyBitmap LineImage = line.ToBitmap(ocrInput);
            int LineX_location = line.X;
            int LineY_location = line.Y;
            int LineWidth = line.Width;
            int LineHeight = line.Height;
            double LineOcrAccuracy = line.Confidence;
            double LineSkew = line.BaselineAngle;
            double LineOffset = line.BaselineOffset;
            foreach (var word in line.Words)
            {
                // Pages -> Paragraphs -> Lines -> Words
                int WordNumber = word.WordNumber;
                string WordText = word.Text;
                AnyBitmap WordImage = word.ToBitmap(ocrInput);
                int WordX_location = word.X;
                int WordY_location = word.Y;
                int WordWidth = word.Width;
                int WordHeight = word.Height;
                double WordOcrAccuracy = word.Confidence;
                foreach (var character in word.Characters)
                {
                    // Pages -> Paragraphs -> Lines -> Words -> Characters
                    int CharacterNumber = character.CharacterNumber;
                    string CharacterText = character.Text;
                    AnyBitmap CharacterImage = character.ToBitmap(ocrInput);
                    int CharacterX_location = character.X;
                    int CharacterY_location = character.Y;
                    int CharacterWidth = character.Width;
                    int CharacterHeight = character.Height;
                    double CharacterOcrAccuracy = character.Confidence;
                    // Output alternative symbols choices and their probability.
                    // Very useful for spellchecking
                    OcrResult.Choice[] Choices = character.Choices;
                }
            }
        }
    }
}