PDF OCR for C#

Or download the DLL directly here

OCR in 1 line of code See All 24 Code Examples

using IronOcr;

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

Install-Package IronOcr

PDF OCR Text Extraction See All 24 Code Examples

using IronOcr;
using System;

var ocrTesseract = new IronTesseract();

using var ocrInput = new OcrInput();

// OCR entire document
ocrInput.LoadPdf("example.pdf", Password: "password");

int[] pages = { 1, 2, 3, 4, 5 };

// Alternatively OCR selected page numbers
ocrInput.LoadPdfPages("example.pdf", pages, Password: "password");

var ocrResult = ocrTesseract.Read(ocrInput);
Console.WriteLine(ocrResult.Text);

Install-Package IronOcr

OCR with Barcode & QR Reading See All 24 Code Examples

using IronOcr;
using System;

var ocrTesseract = new IronTesseract();
ocrTesseract.Configuration.ReadBarCodes = true;
using var ocrInput = new OcrInput();
ocrInput.LoadImage(@"images\imageWithBarcode.png");
var ocrResult = ocrTesseract.Read(ocrInput);
foreach (var barcode in ocrResult.Barcodes)
{
    Console.WriteLine(barcode.Value);
}

Install-Package IronOcr

125 International OCR Languages See All 24 Code Examples

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

Fixing Low Quality Scans & Images See All 24 Code Examples

using IronOcr;
using System;

var ocrTesseract = new IronTesseract();
using var ocrInput = new OcrInput();
ocrInput.LoadImage(@"images\image.png");

ocrInput.Deskew();
ocrInput.DeNoise();
ocrInput.Despeckle();
ocrInput.EnhanceResolution(225);
ocrInput.Sharpen();
ocrInput.Erode();
ocrInput.Dilate();
ocrInput.Scale(200);
var ocrResult = ocrTesseract.Read(ocrInput);
Console.WriteLine(ocrResult.Text);

Install-Package IronOcr

Fast OCR Configuration See All 24 Code Examples

using IronOcr;
using System;

var ocrTesseract = new IronTesseract();

// Fast Dictionary
ocrTesseract.Language = OcrLanguage.EnglishFast;

// Turn off unneeded options
ocrTesseract.Configuration.ReadBarCodes = false;

// Assume text is laid out neatly in an orthogonal document
ocrTesseract.Configuration.PageSegmentationMode = TesseractPageSegmentationMode.Auto;

using var ocrInput = new OcrInput();
ocrInput.LoadImage(@"images\image.png");

var ocrResult = ocrTesseract.Read(ocrInput);
Console.WriteLine(ocrResult.Text);

Install-Package IronOcr

OCR Image Optimization Filters See All 24 Code Examples

using IronOcr;
using System;

var ocrTesseract = new IronTesseract();
using var ocrInput = new OcrInput();
// First load all image(s)
ocrInput.LoadImage(@"images\image.png");

// Note: You don't need all of them; most users only need Deskew() and occasionally DeNoise()
ocrInput.WithTitle("My Document");
ocrInput.Binarize();
ocrInput.Contrast();
ocrInput.Deskew();
ocrInput.DeNoise();
ocrInput.Despeckle();
ocrInput.Dilate();
ocrInput.EnhanceResolution(300);
ocrInput.Invert();
ocrInput.Rotate(90);
ocrInput.Scale(150);
ocrInput.Sharpen();
ocrInput.ToGrayScale();
ocrInput.Erode();

// WIZARD - If you are unsure use the debug-wizard to test all combinations:
string codeToRun = OcrInputFilterWizard.Run(@"images\image.png", out double confidence, ocrTesseract);
Console.WriteLine(codeToRun);

// Optional: Export modified images so you can view them.
foreach (var page in ocrInput.GetPages())
{
    page.SaveAsImage($"filtered_{page.Index}.bmp");
}

var ocrResult = ocrTesseract.Read(ocrInput);
Console.WriteLine(ocrResult.Text);

Install-Package IronOcr

OcrResult Class See All 24 Code Examples

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;
                }
            }
        }
    }
}

Install-Package IronOcr

Create Searchable PDFs by OCR See All 24 Code Examples

using IronOcr;

var ocrTesseract = new IronTesseract();

using var ocrInput = new OcrInput();

ocrInput.LoadImage(@"images\page1.png");
ocrInput.LoadImage(@"images\page2.bmp");

var page = new int[]{ 2, 3 };
ocrInput.LoadImageFrames(@"images\page3.tiff", page);

ocrInput.Deskew();

var ocrResult = ocrTesseract.Read(ocrInput);

ocrResult.SaveAsSearchablePdf("searchable.pdf");

Install-Package IronOcr

Tesseract 5 for .NET See All 24 Code Examples

using IronOcr;
using System;

var ocrTesseract = new IronTesseract();

// This is done by default and can be omitted:
// ocrTesseract.Configuration.TesseractVersion = TesseractVersion.Tesseract5;

using var ocrInput = new OcrInput();
ocrInput.LoadImage(@"images\image.png");
var ocrResult = ocrTesseract.Read(ocrInput);
Console.WriteLine(ocrResult.Text);