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Matrix trailer dynamically uses current time

thechoiceisyours.whatisthematrix.com

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Re: Matrix trailer dynamically uses current time

#191

Post by gregsadetsky »

cwizou wrote: post #169
gregsadetsky wrote: post #164

Earlier quoted context omitted.

Someone posted a trailer they found (that has since been removed) with “7000k” in the url, so… maybe? https://news.ycombinator.com/item?id=28448361 Having looked at it a bit more, I only see "low" and "high" mentioned as qualities. You can replace "high" with "low" in the list of URLs I included (see my gist, posted above) and they seem to work e.g., https://thechoiceisyours.whatisthematrix.com/generated/v7/lo... The…

15k is getting very blue in terms of temperature. Maybe bitrates? Those would also fit.

You've been vindicated, it's definitely bitrate! :-)

See: https://news.ycombinator.com/item?id=28464228

Re: Matrix trailer dynamically uses current time

#192

Post by higgins »

gregsadetsky wrote: post #151
higgins wrote: post #137

Earlier quoted context omitted.

Hmm...each of these videos is rendering the same clips for me. The web player will render new ones though.

The clips are pretty much the same, except for when the time appears on the screen, which happens somewhere in the middle of the videos, no?

At least for me, for each of the videos in that gist the only difference between them was the timestamp at the beginning of the video. All the movie clips were the same. :/

Re: Matrix trailer dynamically uses current time

#193

Post by gregsadetsky »

higgins wrote: post #192
gregsadetsky wrote: post #151

Earlier quoted context omitted.

The clips are pretty much the same, except for when the time appears on the screen, which happens somewhere in the middle of the videos, no?

At least for me, for each of the videos in that gist the only difference between them was the timestamp at the beginning of the video. All the movie clips were the same. :/

Since I first replied to your comment, people have figured out that there's more than just the 'time' (that appears at 0:23 in the video) that changes from one video to another. There are 'parameters' that get encoded in the video file name/URL's MD5 hash as well. Compare these two videos:

Original video file name: blue-a-b1-c1234-d-e1-f-g1-h1-i

which is this url: https://thechoiceisyours.whatisthematrix.com/generated/v7/hi...

Another video file name: blue-a-b3-c0555-d-e3-f-g3-h3-i

which is this url: https://thechoiceisyours.whatisthematrix.com/generated/v7/hi...

Notice the differences due to the b, e, g and h values:

- at 0:13 the video is different

- at 0:18 the video is different

- at 0:23 the displayed time is different (12:34 versus 5:55)

- at 0:35 the video is different

- at 0:39 the video is different

- at 0:42 the video is different

---

This is also really helpful to see all of the clips :-)

https://www.youtube.com/watch?v=MeRmoU7VxIA

Found on https://www.reddit.com/r/matrix/comments/pjww65/whatismatrix...

Re: Matrix trailer dynamically uses current time

#194

Post by chakhs »

nacs wrote: post #176
chakhs wrote: post #150

Earlier quoted context omitted.

I'm disappointed, would've been cool if it was done on the fly

Their static file approach makes sense. There's "only" 1440 combinations and the site is going to get a lot more views than that so why bother re-rendering everything dynamically?

Yes it does make sense. I just wished they did took the re-rendering approach so I could see how it can be done :)

Re: Matrix trailer dynamically uses current time

#195

Post by chakhs »

wahern wrote: post #183
nacs wrote: post #176

Earlier quoted context omitted.

Their static file approach makes sense. There's "only" 1440 combinations and the site is going to get a lot more views than that so why bother re-rendering everything dynamically?

Technically you wouldn't have to re-render (i.e. recompress), you could just dynamically splice in different compressed audio frames. AAC (what MP4 uses) does this well, MP3 less so but for vast majority of listeners it's still indiscernible, especially if there's a slight audio gap. The CPU load is de minimis, though you do still need to track frames--can't just move blobs from disk to socket using sendfile(2). I di…

Thanks that's what I was looking for!

Re: Matrix trailer dynamically uses current time

#196

Post by dynamite-ready »

gregsadetsky wrote: post #154
dynamite-ready wrote: post #147

Earlier quoted context omitted.

Might these not have been cached?

Sorry, what do you mean? In a way, they are “cached” — by being pre-rendered files, all that the web server (s3/cloudfront, really) has to do is serve the file to the user… Are you saying that the video files should have been cached, or..? Thanks

I'm saying that these URL's:

https://gist.github.com/gregsadetsky/cb4754d123f0ea1eae26820...

May have be generated dynamically on the fly (probably programmatically editing / splicing the vids), but the developers, knowing that some people were going save the URLs, cache what's generated for a time so you can access it again without the expense of regen (also splicing in the different clips).

I'm just speculating though. It's part of what makes this promo really cool.

I'd love to see a breakdown. As promo sites go, it's very smart.

Re: Matrix trailer dynamically uses current time

#197

Post by gregsadetsky »

dynamite-ready wrote: post #196
gregsadetsky wrote: post #154

Earlier quoted context omitted.

Sorry, what do you mean? In a way, they are “cached” — by being pre-rendered files, all that the web server (s3/cloudfront, really) has to do is serve the file to the user… Are you saying that the video files should have been cached, or..? Thanks

I'm saying that these URL's: https://gist.github.com/gregsadetsky/cb4754d123f0ea1eae26820... May have be generated dynamically on the fly (probably programmatically editing / splicing the vids), but the developers, knowing that some people were going save the URLs, cache what's generated for a time so you can access it again without the expense of regen (also splicing in the different clips). I'm just speculating tho…

Ah, got it, thanks.

I don’t think that we have definitive proof that the video files are not being generated every time, but most evidence points to that. (There might be some metadata in the mp4 that could help resolve this more definitely)

Considering the complexity of doing on the fly video splicing (even if the results are cached) vs the ability for big studios like WB to do the splicing offline in a controlled environment that they’re used to, it’s probably safe-ish to assume everything was generated in advance.

It also definitely helps with QA - you can be more sure that the splicing worked if you can test some/any/all files before serving them via CloudFront vs relying on a complex-enough piece of tech.

A breakdown of the tech behind this from WB would be interesting to read for sure!

Cheers

Re: Matrix trailer dynamically uses current time

#198

Post by JetSpiegel »

aidenn0 wrote: post #97
modeless wrote: post #52

Earlier quoted context omitted.

I recently realized that in an action movie the hero almost doesn't matter. The villain makes or breaks the movie. Luke Skywalker, John McClane, Neo: they're irrelevant next to Darth Vader, Hans Gruber, and Agent Smith. Hugo Weaving was on fire as Agent Smith in The Matrix. One of the best performances I've ever seen. The interrogation room at the beginning, and the desperation with Morpheus at the end, are just pure…

Counterpoint is action movies where the conflict with the villain is not the primary conflict. e.g. True Lies; sure there's some terrorist stealing nuclear bombs, but that's not what the audience cares about.

True Lies is about a NSA agent using agency powers to spy on his wife, who's not even cheating on him (he just think she is). The bomb plot is just an excuse for the horse chase, and that horrible fighter jet at the end.
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