Beeps in a movie seen at the cinema. Why?

July 18, 2009 3:09 PM

Are movie studios inserting beeps into movies shown at cinemas to spot which cinemas have lax security?

I've just come back from seeing the latest Harry Potter movie (Half-blood prince, here in Switzerland), and there's two fairly obvious "beeps" inserted towards the end of the movie that are certainly not part of the background music, nor are they part of anything that's actually going on (but not that overt that it wrecks the scene/mood of the film). So that got me wondering, is this to catch the cinemas that don't check up on people trying to sneak in video cameras? Eg, the movie studios track the movies sent out to cinemas, somebody films it in the theatre, and torrents it, the movie studio will be able to match the position of the beeps in the movie with the reel sent out to that specific cinema.

posted by slater to media & arts (16 comments total)

Well, they do insert visual marks to identify the source of torrented movies etc... Don't know anything about beeps though. FWIW I was a theatre manager for years and had two of my showings recorded so I know about the tracking.
posted by saradarlin at 3:13 PM on July 18

There used to be visual and audio cues inserted into movies to signal the projectionist to start up the next reel. I'd expect this all to be automated these days, but there still may be a residual cue signal embedded in the sound track.
posted by qurlyjoe at 4:23 PM on July 18

It's to track pirated films to a specific print at a specific theater.
posted by bjork24 at 4:26 PM on July 18

If thats what it is, that's very clever. I never noticed.
posted by Thrillhouse at 4:30 PM on July 18

bjork24: Do you have any evidence of that? It's possible to watermark an audio track in a way that you can't hear, and that can be very difficult to remove if you don't know exactly how it was put in, to the point that running it through all kinds of distortion won't remove.

Loud beeps can be taken out pretty easily.

On the other hand, people have always put beeps in films to mark when reels should be changed. Not all theaters project in digital yet.
posted by delmoi at 7:02 PM on July 18

The dots are easy to spot if you know they exist - and they're annoying. I'll be interested to see if I can hear these beeps.
posted by Sutekh at 8:04 PM on July 18 [1 favorite has favorites]

It does sound like the beeps may be tracking indicators.
About dots:
Cigarette Burns
posted by xorry at 9:26 PM on July 18

Interesting. I too have just come back from the latest HP movie, and noticed the same thing - a few semi-random times throughout the movie, and two or three noticeable times towards the end (without giving too much away - in the underwater scenes). Sounds like short blips of random data in a .wav file, or damaged frames in an .mp3 (anyone remember the MP3PRO format? Sounds like playing one of those on a normal MP3 player).

The last couple in particular aren't in the right place for a reel change. I just put it down to the crap local multiplex, who also like charging extra for the badly-flickering image in their Gold Class. Didn't occur to me that it might be for piracy tracking.
posted by Pinback at 9:59 PM on July 18

pinback: for me, the first beep i noticed was around Gandalf-dude is moving his hand over the rocks, and another one when HP falls into the water.

As for the reel-changing, this is an all-digital cinema, I doubt they need cues to change anything.
posted by slater at 11:56 PM on July 18

delmoi: "Loud beeps can be taken out pretty easily. "

If the beep is taken out, won't there still be an audio dropout in the same point? And if each theater has a different pattern then the pattern will be the same whether it's a beep or silence.
posted by sharkfu at 1:01 AM on July 19

About dots:
Cigarette Burns

Those are to signal the reel change, but there are also "spot patterns" in movies that are different from print to print that are used to track piracy. This article has an example; the second picture down (here) shows spots in the shape of a "T". I notice them most when there's a lot of static, light-colored space on screen.

That article also talks about purposeful audio drop-outs as antipiracy measures, with an example being the last Indiana Jones movie. It wouldn't surprise me if different studios are experimenting with different audio methods.
posted by Karlos the Jackal at 1:29 AM on July 19 [1 favorite has favorites]

If you know what to look for you can also spot the EURion constellation on some prints, though it's far more common on currency.
posted by alby at 4:39 AM on July 19

...audible beeps, however, is just hacky. There are so many more subtle ways.
posted by rokusan at 9:50 AM on July 19

Misbehaving browser must have cut me off...

Audible beeps are hacky. There are so many more subtle ways to insert tracking information, mainly to prevent piracy. I regularly noticed the piracy spots: they're annoying as hell sometimes. Cigarette burns don't irritate me, though, and in fact I sort of like them. They're a part of the movie-going experience and I almost miss their absence in cinemas that exclusively use the digital kind of projectors.

The best ones are really subtle, like a 'scratch' in a corner, or a couple of flickering frames. (Nobody knows that they saw it, but they did.)
posted by rokusan at 5:16 PM on July 21

Rokusan, I'm guessing a moderator removed your first message because spelling "nice big cock" with your underlined letters arguably isn't in the spirit of AskMeFi. I mean, a fight club reference doesn't really help answer the question, does it? But it is confusing when comments are deleted without leaving behind a moderator edit note.
posted by sharkfu at 9:40 AM on July 22

There's always room for nice big cock. And yes, unexplained comment deleting is always confusing. It's one of MeFi's great annoying problems*.

Fight Club is the origin of the term 'cigarette burn', and the point was that there are always new ways to hide information.

Also, way to ruin a joke. This wasn't exactly a question about heart surgery.

*I'm another one.
posted by rokusan at 9:20 AM on August 10