I have been trying to examine a JPEG file, known to contain IPTC data, but could notice no strings whatsoever. I tried the well known UNIX strings command, ASCII, 8-bit, 16-bit Unicode --- to no avail: I could not see any strings that I expect to find in IPTC fields.
My question is: How is IPTC data encoded? Is it encrypted? Compressed? Other? Why can't it be viewed using the strings command?
The most probable reason why you cannot view IPTC data using a hex viewer is because it has no IPTC data.
An image that contains IPTC data like this one:
http://regex.info/exif.cgi?dummy=on&imgurl=https%3A%2F%2Fwww.iptc.org%2Fstd%2Fphotometadata%2Fexamples%2FIPTC-PhotometadataRef-Std2014_large.jpg
has an XML structure and text fields that are view-able through a text editor like Emacs (8-bit, not even Unicode).
