Converting a PDF with color images to grayscale can help you reduce the file size and print the PDF in a more affordable mode without consuming colored ink. In this article, you will learn how to achieve the conversion programmatically in C# and VB.NET using Spire.PDF for .NET.

Install Spire.PDF for .NET

To begin with, you need to add the DLL files included in the Spire.PDF for.NET package as references in your .NET project. The DLLs files can be either downloaded from this link or installed via NuGet.

PM> Install-Package Spire.PDF 

Convert PDF to Grayscale

The following are the steps to convert a color PDF to grayscale:

• Load a PDF file using PdfGrayConverter class.
• Convert the PDF to grayscale using PdfGrayConverter.ToGrayPdf() method.

using Spire.Pdf.Conversion;
 
namespace ConvertPdfToGrayscale
{
    class Program
    {
        static void Main(string[] args)
        {
            //Create a PdfGrayConverter instance and load a PDF file
            PdfGrayConverter converter = new PdfGrayConverter(@"Sample.pdf");
            //Convert the PDF to grayscale
            converter.ToGrayPdf("Grayscale.pdf");
            converter.Dispose();
        }
    }
}

Imports Spire.Pdf.Conversion

Namespace ConvertPdfToGrayscale
    Friend Class Program
        Private Shared Sub Main(ByVal args As String())
            'Create a PdfGrayConverter instance and load a PDF file
            Dim converter As PdfGrayConverter = New PdfGrayConverter("Sample.pdf")
            'Convert the PDF to grayscale
            converter.ToGrayPdf("Grayscale.pdf")
            converter.Dispose()
        End Sub
    End Class
End Namespace

The input PDF:

The output PDF:

Apply for a Temporary License

If you'd like to remove the evaluation message from the generated documents, or to get rid of the function limitations, please request a 30-day trial license for yourself.

Postscript, also known as PS, is a dynamically typed, concatenative programming language that describes the appearance of a printed page. Owing to its faster printing and improved quality, sometime you may need to convert a PDF document to Postscript. In this article, you will learn how to achieve this function using Spire.PDF for Java.

Install Spire.PDF for Java

First of all, you're required to add the Spire.PDF.jar file as a dependency in your Java program. The JAR file can be downloaded from this link. If you use Maven, you can easily import the JAR file in your application by adding the following code to your project's pom.xml file.

<repositories>
    <repository>
        <id>com.e-iceblue</id>
        <name>e-iceblue</name>
        <url>https://repo.e-iceblue.com/nexus/content/groups/public/</url>
    </repository>
</repositories>
<dependencies>
    <dependency>
        <groupId>e-iceblue</groupId>
        <artifactId>spire.pdf</artifactId>
        <version>12.6.4</version>
    </dependency>
</dependencies>

Convert PDF to PostScript

The following are the steps to convert PDF to PostScript.

• Create a PdfDocument object.
• Load a sample PDF file using PdfDocument.loadFromFile() method.
• Save the document as PostScript using PdfDocument.saveToFile() method

import com.spire.pdf.*;

public class PDFToPS {
    public static void main(String[] args) {

        //Load a pdf document
        PdfDocument doc = new PdfDocument();
        doc.loadFromFile("sample.pdf");

        //Convert to PostScript file
        doc.saveToFile("output.ps", FileFormat.POSTSCRIPT);

    }
}

Apply for a Temporary License

If you'd like to remove the evaluation message from the generated documents, or to get rid of the function limitations, please request a 30-day trial license for yourself.

A hyperlink refers to an icon, graphic, or text that links to another file or object. It is one of the most commonly used features for manipulating documents. Spire.PDF for Java supports creating a new PDF document and adding various hyperlinks to it, including ordinary links, hypertext links, email links and document links. This article will show you how to add hyperlinks to specific text in an existing PDF.

Install Spire.PDF for Java

First of all, you need to add the Spire.Pdf.jar file as a dependency in your Java program. The JAR file can be downloaded from this link. If you use Maven, you can easily import the JAR file by adding the following code to your project's pom.xml file.

<repositories>
    <repository>
        <id>com.e-iceblue</id>
        <name>e-iceblue</name>
        <url>https://repo.e-iceblue.com/nexus/content/groups/public/</url>
    </repository>
</repositories>
<dependencies>
    <dependency>
        <groupId>e-iceblue</groupId>
        <artifactId>spire.pdf</artifactId>
        <version>12.6.4</version>
    </dependency>
</dependencies>

Find Text and Add Hyperlinks for Them in PDF

With Spire PDF for Java, you can find all matched text in a specific PDF page and add hyperlinks to them. Here are the detailed steps to follow.

• Create a PdfDocument instance and load a sample PDF document using PdfDocument.loadFromFile()method.
• Get a specific page of the document using PdfDocument.getPages().get() method.
• Find all matched text in the page using PdfPageBase.findText(String searchPatternText, boolean isSearchWholeWord) method, and return a PdfTextFindCollection object.
• Create a PdfUriAnnotation instance based on the bounds of a specific find result.
• Set a URL address for the annotation using PdfUriAnnotation.set(String value) method and set its border and color as well.
• Add the URL annotation to the PDF annotation collection as a new annotation using PdfPageBase.getAnnotationWidget().add() method.
• Save the document using PdfDocument.saveToFile() method.

import com.spire.pdf.*;
import com.spire.pdf.annotations.*;
import com.spire.pdf.general.find.*;
import com.spire.pdf.graphics.PdfRGBColor;
import java.awt.*;

public class SearchTextAndAddHyperlink {
    public static void main(String[] args) {
        //Create a PdfDocument instance
        PdfDocument pdf = new PdfDocument();

        //Load a sample PDF document
        pdf.loadFromFile("C:\\Users\\Test1\\Desktop\\sample.pdf");

        //Get the first page
        PdfPageBase page = pdf.getPages().get(0);

        // Find all matched strings and return the reesult oject
        List⁢PdfTextFragment> results = null;
        PdfTextFindOptions findOptions = new PdfTextFindOptions();
        findOptions.setTextFindParameter(EnumSet.of(TextFindParameter.WholeWord));

        //loop through the find collection
        for(PdfTextFragment find : results)
        {
            // Create a PdfUriAnnotation instance to add hyperlinks for the searched text
            Rectangle2D[] linkBounds = find.getBounds();
            PdfUriAnnotation uri = new PdfUriAnnotation(linkBounds[0]);
            uri.setUri("https://www.e-iceblue.com/Introduce/pdf-for-java.html");
            uri.setBorder(new PdfAnnotationBorder(1f));
            uri.setColor(new PdfRGBColor(Color.blue));
            page.getAnnotationsWidget().add(uri);
        }


        //Save the document
        pdf.saveToFile("output/searchTextAndAddHyperlink.pdf");
    }
}

Apply for a Temporary License

If you'd like to remove the evaluation message from the generated documents, or to get rid of the function limitations, please request a 30-day trial license for yourself.