The World of WarCraft fanatics over on the OwendCore forums have uncovered what they claim to be evidence of Blizzard embedding World of WarCraft user ID info into screenshots taken in-game.
There was a lot of sleuthing involved, with much discussion about disassembling the .JPG compression algorithm for the screenshot routine, ruling out compression artefact theory, and possible reasons for Blizzard doing this in the first place.
To see the watermarks, one has to go to extreme lengths, taking a shot of an area of flat, bright texture, and then twiddling in an image program to sharpen and enhance the image until the watermarks stand out to the human eye.
The end result looks something like this:
Another screenshot, with high contrast added to emphasise the watermarks:
This appears as some sort of custom matrix bar-code (like the familiar QR-Codes) which Blizzard can presumably decode to obtain information about who took the screenshot.
It is believed that the following information is embedded: Account Name, Realm Info (Serialized, unknown content), Realm IP, Timestamp.
It appears that the watermarks are created as a function of the WoW screenshot tool, but only at compression quality levels of 1-9 (with the default value being 3). This value can be changed via console commands; but what is strange is that, on maximum quality (10), the watermarks do not appear.
Further backing up the notion that WoW’s in-game screenshot function is the culprit, is the fact that using a screen capture program such as Fraps doesn’t result in the same watermarks appearing.
With no official word from Blizzard on the matter, current theories peg it as a method of identifying those who have posted evidence of in-game exploits being abused.
During a developer Q&A on Reddit yesterday evening, the question was posed to Blizzard about the purpose of these watermarks, but no asnwers were forthcoming.
What do you think? Storm in a teacup, or massive Activion-Blizzard conspiracy? Let us know in the comments below and on the MyGaming forum.
Source: Ownedcore
Related Articles
World of WarCraft patch drops, prepares for Mists of Pandaria
Blizzard bans Iranian players from World of WarCraft


I’m actually a retired moderator from the OwnedCore forums, you can contact me under the username UnholyShaman if you have any questions.
Something I wish to add is that the Account Name information isn’t your logon email address. It’s your Account Name in ID format (so it will appear in a series of numbers). This means it’s only useful to Blizzard and cannot directly increase the risk of your account being compromised in anyway (just wan’t to reassure people).
Someone can’t extract that Account ID, enter it in and start bruteforcing or guessing your password. Blizzard only accepts email accounts as a logon username.
I find it very interesting that Blizzard hasn’t apparently made use of this identification method which makes me wonder how capable they are of actually extracting it out of a normal screenshot. Sure non-Blizzard employees on OwnedCore forums have figured out how to extract the information, but only when it’s presented against a plain coloured background.
I’ve been privy to a lot of the top hacks/exploits posted with screenshots to back it up in the upper levels of the OC forums and if this watermark embedding really was used to catch punish hackers and exploiters then Blizzard would have had a field day by now.
The only conclusion I can think of is A) they are using it purely for statistical gathering and market research of some kind, or B) as mentioned, to identify a server. If someone posts a very abusive exploit, Blizzard are going to want to know if this was performed on live realms or on a fake server.