How to provide WebP and Avif image versions through a Java Servlet?

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To provide WebP and Avif image versions through a Java Servlet, follow the below steps:

1. Install the necessary packages:

   • To convert images to WebP format, install WebP toolkit
   • To convert images to Avif format, install libavif library

2. Create a servlet that will handle the image requests and convert the image to WebP and Avif formats.

3. In the servlet, first check if the client's browser supports WebP or Avif formats. Use the "Accept" header of the request to check if the browser supports WebP or Avif format.

4. If the client's browser supports either WebP or Avif format, then use the appropriate conversion tool to convert the image to that format.

5. Set the response header to indicate the content type of the converted image.

6. Return the converted image.

Here's a code snippet to convert an image to WebP format in a Java Servlet:

import org.webpki.WebPki;

// ...

// Convert image to WebP
byte[] webpData = WebPki.encodeImage(imageData, width, height, quality);
response.setContentType("image/webp");
response.getOutputStream().write(webpData);

Similarly, here's a code snippet to convert an image to Avif format:

import org.libavif.AV1Image;
import org.libavif.AvifCodec;
import org.libavif.AvifRGBImage;
import org.libavif.Frame;
import org.libavif.JniBridge;

// ...

// Load the image data
AvifRGBImage rgbImage = new AvifRGBImage(imageData, width, height, AvifRGBImage.ColorPrimaries.BT709, AvifRGBImage.TransferCharacteristics.SRGB, AvifRGBImage.MatrixCoefficients.BT709);

// Convert image to Avif
AV1Image av1Image = rgbImage.toYUV(AV1Image.ColorRange.LIMITED, AV1Image.ChromaSamplePosition.UNKNOWN);

Frame frame = new Frame(1, av1Image, null);
AvifCodec codec = new AvifCodec();
byte[] avifData = codec.encodeJni(JniBridge.avifEncoderCreate(), frame);

response.setContentType("image/avif");
response.getOutputStream().write(avifData);

Note: You may need to adjust the code snippets based on your specific use case.