public void handleCommentTags(Directory directory, Metadata metadata) {
            if (metadata.get(TikaCoreProperties.DESCRIPTION) == null &&
                    directory.containsTag(ExifIFD0Directory.TAG_IMAGE_DESCRIPTION)) {
                metadata.set(TikaCoreProperties.DESCRIPTION,
                        directory.getString(ExifIFD0Directory.TAG_IMAGE_DESCRIPTION));
            }
        }
EXIF may contain image description, although with undefined encoding.
Use IPTC for other annotation fields, and XMP for unicode support.
tika-parsers/tika-parsers-standard/tika-parsers-standard-modules/tika-parser-image-module/src/main/java/org/apache/tika/parser/image/ImageMetadataExtractor.java