Convert JPEG XL to PDF in Java

JDeli is a pure Java library that converts JPEG XL to PDF without native dependencies. It accepts File, InputStream, and byte[] input, and supports batch conversion from the command line.

JPEG XL (.jxl) is a next-generation image format designed as a long-term replacement for JPEG, offering improved compression and lossless support. Browser and software support for JPEG XL is still limited.

Why use JDeli instead of Java ImageIO

Java’s built-in ImageIO cannot read JPEG XL or write PDF. JDeli provides native support for both with no native dependencies required.

To run the code examples you will need to download the JDeli jar:

Download JDeli

Convert JPEG XL to PDF in one line of code

The JDeli.convert() methods allow you to save JPEG XL as PDF in just ONE line of code!

Using File

JDeli.convert(File inFile, File outFile);
JDeli.convert(File inFile, EncoderOptions encoderOptions, File outfile);
JDeli.convert(File inFile, File outfile, ImageProcessingOps imageProcessingOps);

Using InputStream and OutputStream

JDeli.convert(InputStream inputStream, OutputStream outputStream, "pdf");
JDeli.convert(InputStream inputStream, EncoderOptions encoderOptions, OutputStream outputStream);
JDeli.convert(InputStream inputStream, OutputStream outputStream, ImageProcessingOps imageProcessingOps);

Using byte[]

byte[] outputData = JDeli.convert(byte[] inputData, "pdf");
byte[] outputData = JDeli.convert(byte[] inputData, EncoderOptions encoderOptions);
byte[] outputData = JDeli.convert(byte[] inputData, "pdf", ImageProcessingOps imageProcessingOps);

Batch convert JPEG XL to PDF from command line

Change image formats from command line or bash, bat, and powershell scripts. This method can also be used to invoke JDeli from any programming language that allows you to create a child process.

java -jar jdeli.jar --convert pdf "inputFileOrDir" "outputDir"

How to convert from JPEG XL into PDF in Java as separate steps

Sometimes there is a requirement to convert between formats as separate steps. JDeli also allows the image to be read in as a BufferedImage and then written out later.

1. Read JPEG XL image into Java

   BufferedImage bufferedImage = JDeli.read(new File("jxlImageFile.jxl"));  
   

2. Process image if needed (scale, sharpen, lighten, watermark, etc)

   bufferedImage = operations.apply(BufferedImage bufferedImage); // Optional
   

3. Write out BufferedImage as PDF image file

   JDeli.write(bufferedImage, "pdf", new File("pdfImageFile.pdf"));
   

Frequently asked questions

Does Java support JPEG XL and PDF natively?
No. ImageIO cannot read JPEG XL or write PDF. JDeli adds native support for both with no additional installation.

Can I convert JPEG XL to PDF without installing native libraries?
Yes. JDeli is a pure Java library. It runs on any platform where the JVM runs with no additional installation.

What input types does JDeli accept for JPEG XL conversion?
JDeli accepts File, InputStream, and byte[] as input. Output can be written to a File, OutputStream, or returned as byte[].

Can I process the image during conversion?
Yes. All JDeli.convert() variants accept an ImageProcessingOps parameter, so you can scale, sharpen, watermark, and apply other operations in the same step. The two-step read/write approach also supports this if you need more control.

View Javadoc

Related conversions

See the JDeli conversion overview for a full list of supported format conversions.