While that can happen (sometimes cinemas can actually get a license to show a movie off a bluray disc), typically there's dedicated playback servers showing a much higher quality version of the movie (think about 600GB for a movie).
Pretty much! Every frame is a separate JPEG2000 at almost lossless quality.
That's 10× more data than a typical 4K UHD Blu-ray, with 64 times more color depth than Dolby Vision.
And the sound is for trailers typically uncompressed 5.1 surround, for most movies 1024 channels of lossless Dolby Atmos, or with IMAX lossless 12.1 surround.
That is because the theater screen on average measured 800 inches diagonally whereas most people home TV screen average 65 inches. Same reason why a 1080P youtube video look better on your phone screen vs your 4k 27" monitor.
Mostly feel the same, though for IMAX in particular. The Manchester Printworks Vue (UK)'s 70mm IMAX presentations usually have film noise or slight blurriness in general, though that's probably more to do with the film itself as opposed to projection quality.
Compared to streaming yes, that's a noticeable difference to quite a few people. But I doubt that if you played that quality vs a 4K BluRay on the same screen that there is that huge of a difference that people would notice.
Last time I went to the movies the projector screen was dirty. Which meant the brighter the image, the more apparent any flaws in the screen were. And also the black levels for projection just sucks compared to a modern OLED. Flaws of a theater are more apparent than what Blu-ray compression would be.
Theres one cinema we go to where some prick clearly threw a milkshake at the screen and apparently the cost to clean it is somehow too much for the cinema to bother with. As you say its noticable in bright scenes. Its like an infuriating dead pixel once you know about it.
It truly doesn’t matter, because you’re sitting so much further from the 85 foot screen.
My understanding of the development “HD” format is that it was more or less designed to be similar to sitting in the middle of a movie theater watching a normal screening print. My experience of having watched movies off of a 35 mm projector for many years, followed by some years of watching standard blu rays get sometimes played in movie theaters, is that they got it about right.
The one exception is well-shot black and white movies, which have much more dynamic range than the HD blu ray format allowed for, but 4K UHD discs are basically reference quality even for those.
Yep, many times actually. The angle of the seating and size of the screen is the amazing part. But it seems like the quality of those isnt what they used to be.
Funny thing about IMAX, is they are not all the same. They really should be if they are marketed as IMAX.
That's not correct at all. Most devices do very little on the fly "sharpening"; it's not an effective strategy anyway, you can't magic away compression artifacts.
Compression algorithms are just extremely efficient at keeping half-decent images even at awful bitrates.
I bet you would easily notice the difference on a large theater screen in the dark. There is a vast gulf of what is noticable to the eye with that set up vs even high quality TV panels.
Most cinemas have usually something like 64 actual speaker channels, but that's the point of Atmos (or DTS:X), object-based surround sound automatically mixed for whatever speaker configuration the local cinema has.
(In contrast to the old times, when cinemas had 5.1 channels with 5-10 speakers per channel)
The movies at my local AMC look like total shit unless you’re in one of the only two big auditoriums. The other 14 screens are complete and utter crap. They’re unbelievably dim, and no amount of polite complaints to the local staff or via their website has resolved it. Thanks, AMC! /s
Its done with software using object-oriented sounds in 3D space. "dolby atmos" is one example of such software.
The idea is you want the your explosion sound or whatever to sound like it's coming from the same direction with the same volume in every theater no matter what the speaker configuration is. So instead of a fixed master track tuned to a specific speaker layout, the audio system gets a command saying "make this sound come from XYZ coordinate in your theater" and it does some processing in realtime to figure out the exact volume and timing (phase) each speaker needs to use to fullfil that command.
To come back to your question on the number of channels, that defines your maximum resolution. More channels = more precise beam forming. Idk about the 1024 number. That does seem to high to me. But idk, it's possible. Audio processing is cheap these days
Basically, once you go beyond 12.1, each cinema will have a different speaker configuration.
So instead you have each individual object as a separate track, in the scene positioned in 3D space, and typically a Dolby Atmos processor that then mixes that automatically for the specific speaker configuration of each cinema.
So indeed pretty much close to what I was imagining. Except hopefully you just specify how your speakers are positioned in some kinda virtual room, and the thing calculates the mix itself.
This must be a nightmare for the studio's audio engineers too. I'm gonna guess most films don't use anywhere near the whole 1024 channels.
All that and then you have an uncalibrated projector with chromatic aberration all over the picture. Totally skewed and flickering luminosity.
That's where I saw backroom. At least half the time there was a vhs look over the image so the poor image quality wasn't so important. But come on, if I'm paying 15 for a 2h screening theater better up their rig
And if you're in a non-english country, the sound is often also dubbed.
There's a reason why I only watch movies either in IMAX with Laser 4K in the original language, or at home (with an OLED and proper Dolby Atmos 5.1.4 system, not a soundbar).
Usually the contrarians who just sort by top to find a bunch of movies they've pretended they've seen and pretend they don't like at least try to copy and paste points they've seen from negative reviews online, it's funny that you guys just literally can't find any for this movie lol
That's not uncommon still, a lot of games the majority of the game size is in audio and video files still, for a while it was a not uncommon process to delete other languages + story mode voice files + other languages in games to make the file size drastically smaller.
As a consumer, the best quality of movies I can buy is the 4K UHD version. If I rip it losslessly to my PC I usually end up with a 60gb file that has a bitrate of 60Mb/s.
Same with PS1 games. CDs were about 600MB and even at 420p FMVs and mp3 audio used the bulk of that space, hence why FMV heavy games like Final Fantasy came on multiple disks.
Well, if you simply encode each frame as lossless webp, you already get lossless video compression.
FLAC and other lossless audio codecs apply pure mathematical compression that allows reconstructing the original stream, only they account for playback realities such as seeking. It's no surprise that the same can be done with video.
Is that maybe for the 2K dual projection systems, or for movies with more typical runtimes? Because the previous 3h movie 4K DCPs I've seen were around 500-600 gigs.
Both from extrapolating the trailer sizes, and from extrapolating the pixel count of the different releases, you'd expect the IMAX 1.43:1 DCP to be around 500GB.
8k imax must be huge... Looks like just a normal 8k dcp would be about 17TB raw, ~8.5TB losslessly compressed... plus, like 10GB probably for sound or so?
imax often does double camera so it may be 34TB/17TB? And if they mess around with 60fps... 85TB...
I read they receive hard drives that have the movie on it? Regal has been doing a ton of older movies on and off since September. I remember the day they were supposed to show Saving Private Ryan got delayed because they didn't receive the hard drive in time.
sometimes cinemas can actually get a license to show a movie off a bluray disc
And sometimes they just don’t care.
Also, it’s possible that some theater rentals for normal birthday parties and stuff fall under “exhibition” laws, but in practice I doubt studios care, and those are usually “bring your own blu ray.”
That doesn't sound right. The system for digital movie distribution is heavily locked down and tightly integrated with the studios themselves, to the point that the actual theaters barely have any control over showtimes and when/how a movie starts. I'm not sure how a theater would be able to play a new release digital movie through VLC. Movies released in DCP are encrypted and to my knowledge there is no way to acquire the keys or decrypt the files unofficially.
They probably used VLC for the trailers, or in some rare cases cinemas can also get a license to play movies off of consumer blu ray discs, but that's typically only for films that have long been released.
Even the proper cinema projectors usually have an HDMI input.
In larger cinemas you'll typically see one set of ads (usually local businesses, car ads, ice cream, etc), then a few seconds of darkness, followed by movie trailers and maybe one or two ads. The first half is usually played from regular video files such as .mp4, while the second half are actual cinema packages (DCP). Often the first half is played from a different projector or via the HDMI in.
Oh darn, those are expensive. Understandably. My hopes of seeing that original Avatar trailer in glorious quality, not obliterated by 17 years of compression are dashed. :(
Thank you for the info. I assume that, hypothetically, even with a DCP server or something like easyDCP there aren't really DCPs to watch for a normal (non-rich) person? Just curious.
Most likely scenario is that they don't live in the USA (or a country with formal distribution channels for movies) in some smaller countries it's very common for theaters to show bootleg copies of movies.
This won't happen in the USA though (or at least if it does happen, the theater won't stay on business very long).
Do... Do you not live somewhere dense enough for there to be an indie theater? Because indie theaters have a lot of freedom compared to your standard corporate chain while still getting a select few new releases.
How would they do that in this scenario? When Avatar was released, there was no ability then or now to access the unencrypted DCP files to be able to play the movie through VLC. You can certainly do it now after the movie has been out on streaming and DVD/Blu-ray. It's trivial to play a pirated or legit copy of the movie, but definitely not when it was originally released in theaters.
They do basically download the movies now, but they have to play at such a high bitrate. Many theater-quality movies are essentially 1080P, but because of the bitrate they are so much better.
We went to a theater to watch Wonka (2023) and it looked and sounded exactly like a cam pirated copy. Low resolution, flat color, terrible echoey sound. It was such poor quality that we walked out. (And this was at a big national chain.)
Went home and searched the internet for a way to watch the movie with better quality and found the movie with the exact same shitty quality as the theater. Waited a couple of months and were able to finally watch the movie with the "good" quality.
I'm quite positive that the theater pirated the movie instead of paying for it. Has anybody heard of or experienced this?
I definitely figured they moved to something digital after all the cinemas revamped for high death. It's hilarious that they use VLC.
Also, I remember back in the day the girl I went on a date with to go see The Matrix had seen it before but she said she was fine seeing it again.
In the scene where Cypher betrays Neo suddenly the film literally melted onscreen. The theater got it back up and running quickly, however it was after all the action happened and the scene played out. I freaked out wondering what I missed and then remembered that my date had seen it before and luckily she filled me in on what happened. It was kind of worth missing that scene because I had never seen that happen in a movie before (and now probably never will again).
4 frames per foot at about 50mb each is something like 410tb of footage. Tough squeeze for a usb drive, I’d say.
Compression techniques could save a lot but to replicate true 1:1 imax footage would be a crazy amount of data.
nah in regular photography its indistinguishable because its rare to get perfect lighting conditions. but under studio lights thats where film surpasses digital. you are talking about pixels vs molecules
You're talking about pixels vs film grains, and there is a functional resolution limit for the grain of film (especially considering the image is printed on a tiny rectangle that gets blown up).
We're also talking human eye, and beyond 4k there are massively diminishing returns on what people can distinguish. High bitrate 4k digital is gloriously sharp to the human eye, you aint getting anything extra in the experience from 70mm. It's all bluster and theatre.
for a 34 inch monitor maybe but even then you get a very noticeable difference going from 4k to 5k let alone 16k. with a 888 inch screen the pixel density for 4k is going to be worse than 1080p on a 34 inch monitor. sure the viewing distance is going to help but you are still not going to see as much details at 4k
There's a arthouse theatre in my city that does this type of thing. I couldn't believe it but I got there early for a couple of screenings and while waiting, sitting in the theatre the projectionist is setting up and pulls up VLC on a windows 10 computer and browses to the movie file on a removable drive. Even knowing this now I still go back since they have A/C, a bigger screen and way better sound system than I have at home, plus it supports a small business.
I mean what else were you expecting? VLC is a very solid media player and most movies being shown are digital. It's always going to just be some media player program on a computer.
VLC does not actually support the format most movies use (believe me, I've tried... — ffmpeg doesn't have support for the colorspace), but it's frequently used for trailers and in some rare cases also in cinemas.
That's silly. They have different UIs, and different configurations, but they're all just running ffmpeg's ffplay under the hood.
MPV and MPC have different defaults that work better for pirated media, especially anime, but for any regular usage there's absolutely no difference. You can even just use ffplay directly without any UI, and it'll look and sound the same.
And even then, cinemas typically don't use any of that, but doremi as playback software, christie or dolby playback servers for playback and projector control, and Dolby's hardware decoders for audio.
ffplay is a separate barebones player FFmpeg ships for testing, none of these use it. What they actually share is libavcodec for decoding, and decoding isn't where quality differs. Color range mapping, scaling and dithering happen in each player's own renderer, and VLC has documented full vs limited range bugs on Windows that crush blacks or wash out the image. Same decoded frames, different picture. And the cinema hardware point doesn't apply, the whole thread is about a cinema that literally uses VLC.
Color range mapping, scaling and dithering happen in each player's own renderer, and VLC has documented full vs limited range bugs on Windows that crush blacks or wash out the image.
None of which matters in a cinema, where no scaling or colorspace conversion happens.
Regarding dithering, that's only an issue if you're watching typical pirated anime encodes, which, guess what, a cinema typically isn't.
the whole thread is about a cinema that literally uses VLC.
Which I'd contest anyway, it's possible the trailers before the movie were shown via VLC, but the movie itself cannot be shown via VLC (yet).
You're describing a DCP server chain, this isn't one. It's a Windows PC outputting to a projector, so colorspace conversion (YCbCr to RGB, full/limited range mapping) happens on every frame, which is exactly where VLC's documented bugs are. Scaling happens too unless the file matches the projector's native res, which it won't.
Dithering isn't just an anime encode thing, it applies whenever bit depth drops. And OP literally watched them open a regular movie file in VLC, so there's nothing to contest. VLC even has a DCP module with KDM support anyway, it's just too slow to be practical.
Last time I read up on this, the file format was essentially one standalone JPEG per frame, all concatenated together, which is pretty low tech. Modern video formats only send a whole image every few seconds and then make little adjustments to it, essentially working the still image of someone's face like a puppet to make their mouth move. This is why when a keyframe got dropped, you sometimes see a brick wall with a mouth and eyes that move, and it's all made of brick.
Most modern projection booths have a dedicated server that allocates what houses the movies play or have the movies directly ingested into the projector (it's a long process and a pain in the ass when moving film around). They're mostly sent in via satellite, but some are sent on large hard drives.
The sound keys are sent separately and are encrypted for that specific copy of the movie. The files for both are also massive.
I used to be the manager at my hometown theater, it was the first all digital theater in the state (though, there were three .35mm projectors because Hollywood hadn't made the transition to all digital back in 2006). Because it was so new, we had a lot of hiccups - took over a year to install the film server, another to fully automate movie start times and allocations. But, it kept me in shape as I had to run up and down a few flights of stairs about 6+ times a day.
It is mostly. There's like 10 theaters in the country, and ~30? worldwide that will show the film like this. 70mm IMAX is the "true" IMAX format, it's a totally different aspect ratio that makes the image almost square (think like 2 IMAX screens stacked). It's HUGE and incredibly impressive visually.
For how much people praise VLC I'm always amazed when people want watch a newer movie using it unless it's just some torrent with surround sound stripped.
Been using it for forever and I only use it on old video and corrupted video.
New movies are encrypted on a special hard drive sent to you by the studio. You have to upload the movie and the encryption key to the projector hard drive.
For old movies you can just pay for the temp screening rights and play whatever format you want, generally speaking
I used to work at a cinema. That’s what we did to play the movies. It was all digital and regular staff weren’t allowed in the projector hallway without a manager.
Went to see interstellar in 70mm a few years ago. Drove 4h to the nearest theater, booked tickets a month ahead. Arrive at 10pm and they informed us that the projector broke early in the day and they would be playing a digital copy instead.
On the bright side I complained about their poor communication and they gave me a full refund.
If any theater used VLC I'd never go there again. MPV and MPC both provide higher image quality, theaters should be using the best which VLC objectively isn't.
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u/moomzzz Jul 16 '26
Here’s me thinking they just plug in a usb somewhere and crack open VLC player on the big screen