years-enron/webp-imageio

Java ImageIO WebP support

Forked repository

This is a fork from luciad/webp-imageio

Changes

• Native libs are bundled in the jar
• Published to Maven Central (org.sejda.imageio:webp-imageio artifact)
• Android support unknown (have not tested)

Supported platforms

• windows (32, 64 bit)
• linux (64 bit)
• mac (64 bit)

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Description

Java Image I/O reader and writer for the Google WebP image format.

License

webp-imageio is distributed under the Apache Software License version 2.0.

Usage

• Add Maven dependency org.sejda.imageio:webp-imageio to your application
• The WebP reader and writer can be used like any other Image I/O reader and writer.

Decoding

WebP images can be decoded using default settings as follows.

BufferedImage image = ImageIO.read(new File("input.webp"));

To customize the WebP decoder settings you need to create instances of ImageReader and WebPReadParam.

// Obtain a WebP ImageReader instance
ImageReader reader = ImageIO.getImageReadersByMIMEType("image/webp").next();

// Configure decoding parameters
WebPReadParam readParam = new WebPReadParam();
readParam.setBypassFiltering(true);

// Configure the input on the ImageReader
reader.setInput(new FileImageInputStream(new File("input.webp")));

// Decode the image
BufferedImage image = reader.read(0, readParam);

Encoding

Encoding is done in a similar way to decoding.

You can either use the Image I/O convenience methods to encode using default settings.

// Obtain an image to encode from somewhere
BufferedImage image = ImageIO.read(new File("input.png"));

// Encode it as webp using default settings
ImageIO.write(image, "webp", new File("output.webp"));

Or you can create an instance of ImageWriter and WebPWriteParam to use custom settings.

// Obtain an image to encode from somewhere
BufferedImage image = ImageIO.read(new File("input.png"));

// Obtain a WebP ImageWriter instance
ImageWriter writer = ImageIO.getImageWritersByMIMEType("image/webp").next();

// Configure encoding parameters
WebPWriteParam writeParam = new WebPWriteParam(writer.getLocale());
writeParam.setCompressionMode(ImageWriteParam.MODE_EXPLICIT);
writeParam.setCompressionType(p.getCompressionTypes()[WebPWriteParam.LOSSLESS_COMPRESSION]);

// Configure the output on the ImageWriter
writer.setOutput(new FileImageOutputStream(new File("output.webp")));

// Encode
writer.write(null, new IIOImage(image, null, null), writeParam);

Compiling

Compiling the native library for Java SE

• Install CMake 2.8 or newer. CMake can be downloaded from www.cmake.org or installed using your systems package manager.
• Install VS 2017 Community and make sure the C++/Cmake dev tools modules are installed
• Create a directory called build in the root of the project
• Open a terminal and navigate to the newly created 'build' directory
• Run cmake .. in the 'build' directory to generate the build scripts for your system. On Windows 64 bit run cmake -DCMAKE_GENERATOR_PLATFORM=x64 .. to get a 64 bit dll.
• cmake --build . --config Release to compile the library
• The compiled library can be found under the directory build/src/main/c
• Copy the compiled library to src/main/resources/native/$platform/$bits

Compiling the native library for Android

• Install the Android NDK.
• Run ndk-build in the src/android directory
• After completion libwebp-imageio.so can be found under src/android/libs/<abi>

Compiling the Java library

Using Maven

• Run mvn clean test in the root of the project
• The compiled Java library can be found under the build directory
• Run mvn release:prepare release:perform -Prelease -Darguments="-Dgpg.passphrase=secret123 -DstagingDescription=sambox" to upload to OSS Nexus, then login and publish to Maven Central