How to read WMF images in Java

In this post, I will show you how to read WMF images in Java. We also have a related article covering how to convert WMF to SVG files in Java that might interest you.

ImageIO does not support WMF file types by default so you will need to use an ImageIO plugin or an external library. I will demonstrate using an Open source ImageIO plugin called TwelveMonkeys (which extends ImageIO to provide WMF reading support), and using the JDeli Image Library.

What is WMF?

Windows Metafile (WMF for short) is an image file format developed by Microsoft, which has the capabilities for both vector and bitmap images. It is more commonly used for its vector capabilities, similar to a file format such as SVG. Note that once you have loaded a WMF file into a BufferedImage, it has been converted into a bitmap image and is no longer a vector format.

The file name extension for WMF files is: .wmf

How to read a WMF image in Java with ImageIO

1. Download TwelveMonkeys plugin and add to class path.
2. Create a File handle, InputStream or URL pointing to the raw WMF image.
3. ImageIO will now be able to read a WMF file into a BufferedImage. This syntax is like so:

   BufferedImage image = ImageIO.read(wmfFileOrInputStreamOrURL)

How to read a WMF image in Java with JDeli

1. Add JDeli to your class or module path. (download the trial jar).
2. Create a File handle, InputStream pointing to the raw WMF image. You can also use a byte[] containing the image data.
3. Read the WMF image into a BufferedImage

   BufferedImage image = JDeli.read(wmfFile);

Why do developers choose JDeli over free alternatives?

1. Works with newer image formats such as AVIF, HEIC, JPEG XL, WEBP (AVIF next release) that are not supported in Java.
2. Better support than alternatives for JPEG, PNG, TIFF.
3. Process images up to 3x faster than ImageIO and other Java image libraries.
4. Prevent JVM crashes caused by native code in other image libraries such as ImageIO.
5. Image security as JDeli processes images on your servers with no calls to any external system or third party library.

// Read an image
BufferedImage bufferedImage = JDeli.read(dicomImageFile);

// Read an image
BufferedImage bufferedImage = JDeli.read(heicImageFile);

// Write an image
JDeli.write(bufferedImage, "heic", outputStreamOrFile);

// Read an image
BufferedImage bufferedImage = JDeli.read(jpegImageFile);

// Write an image
JDeli.write(bufferedImage, "jpeg", outputStreamOrFile);

// Read an image
BufferedImage bufferedImage = JDeli.read(jpeg2000ImageFile);

// Write an image
JDeli.write(bufferedImage, "jpx", outputStreamOrFile);

// Write an image
JDeli.write(bufferedImage, "pdf", outputStreamOrFile);

// Read an image
BufferedImage bufferedImage = JDeli.read(pngImageFile);

// Write an image
JDeli.write(bufferedImage, "png", outputStreamOrFile);

// Read an image
BufferedImage bufferedImage = JDeli.read(tiffImageFile);

// Write an image
JDeli.write(bufferedImage, "tiff", outputStreamOrFile);

// Read an image
BufferedImage bufferedImage = JDeli.read(webpImageFile);

// Write an image
JDeli.write(bufferedImage, "webp", outputStreamOrFile);