if (discNum != null) {
metadata.set(XMPDM.DISC_NUMBER, discNum.getA());
}
// Compilation
AppleCompilationBox compilation = getOrNull(apple, AppleCompilationBox.class);
if (compilation != null) {
metadata.set(XMPDM.COMPILATION, (int)compilation.getValue());
}
// Comment
AppleCommentBox comment = getOrNull(apple, AppleCommentBox.class);
addMetadata(XMPDM.LOG_COMMENT, metadata, comment);