Question

How can I read the metadata of a JPG image in Java using BufferedImage, and then encode it as JSON?

Answer 1

The MetadataExtractor can be used to extract metadata like Exif, IPTC… and more, http://www.drewnoakes.com/code/exif/

The following snippet will print metadata found in file:

Metadata metadata = ImageMetadataReader.readMetadata(file);
Iterable<Directory> directories = metadata.getDirectories();
Iterator<Directory> iterator = directories.iterator();
while(iterator.hasNext()) {
    Directory dir = iterator.next();
    Collection<Tag> tags = dir.getTags();
    for(Tag tag: tags) {
        System.out.println(tag.getTagName() + "  " + tag.getDescription() + " " + tag.getTagTypeHex());
    }
}

This snippet uses the latest release candidate, http://code.google.com/p/metadata-extractor/downloads/detail?name=metadata-extractor-2.5.0-RC3.zip&can=2&q=

At least that’s a start with the extraction, which I believe is the hard part.