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Comment by babypuncher | Hacker News Reader

I'm not sure I like the idea of a film's photography potentially looking different based on the decoder used. I would much rather dedicate additional bits to preserving the noise that was present in the original film stock or added during post-production.

Storage and bandwidth are only getting cheaper.

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That goal might already have been somewhat lost years ago. The video almost everyone after the editors watch has been re-encoded at least once (more likely twice) with one or more different codecs that definitely change the character of the video from that of the source. Any same source content will already look noticeably different depending one which service or provider you’re using, since they each have their own opinionated video content encoding and distribution pipelines. If you’re talking about archival storage in the sense of preserving masters, then I definitely agree and the film grain removal should be disabled in the encoder, so the decoder-side synthesis won’t happen. Thankfully, that’s very easy to do (for example, libaom-av1 encoder in ffmpeg supports denoise-noise-level parameter set to zero to disable those scary parts.)

No one is archiving with av1 and no one ever will. It's all film out, DPX sequences, and prores 4444 for the vast majority of things I've encountered as a post professional.

Even the editors don’t usually use the original files but they get transcoded to proxy format for editing.

> I'm not sure I like the idea of a film's photography potentially looking different based on the decoder used.

Well it says the noise is specified exactly by the bitstream. I'm not sure how much lenience there is for the decoder in the postprocess option.

Funnily, I also don't like these techniques but that's because I'd rather eliminate the noise myself and have a noiseless image when possible. Grain, to me, is simply annoying. Adding it and preserving it has little value.

in that case, this is still probably a good feature for you since you can make an encoder that just doesn't re-synthesize noise and you'll get a de-noised picture.

Not really, because these encoders are (generally speaking) making pretty large compromises with their noise filters in order to be timely. I want to spend the extra time doing motion compensated denoising.

These noise filter will sometimes be temporal, rarely will be motion compensating (because that's computationally expensive) and as a result can't get as good a result as I can.

In subjective tests, normal people often report grain (real or reconstructed) as a defect so you're probably in the majority of viewers. Creators and codec nerds value them more than the audience.

So these grain removal techniques are in many ways a political compromise between people who just want the smaller video, and the people who want the grain.

I'd be fascinated to see how codecs with and without this feature diverge in terms of encoding changes. Presumably there were some big gains just sitting there but the minority that preferred grain stopped then being exploited.

Much of the drama around encoder quality has came down to this dichotomy. Choosing to lose the grain/detail was attacked as plastic or fake by the people who care about it, while people who didn't could point to better test scores. Which then caused more arguments about the validity of the measures.

I am a film person (director, camera guy, work in post production). Grain is an aesthetic choice and has an effect on the perception of an image.

Sure, for the typical Hollywood blockbuster it has not much value and can break the immersion, but for everything else grain can make you look on a picture, rather than into it. This could be the difference between looking through a window and looking at a painting for example. Additionally grain can emphasize the passing of time. A shot of a still life without grain is something different from the very same shot with grain.

Today it is just another tool in the aesthetical toolbox. And someone somewhere decides when to have it and when not to have it.

Exactly this, there have long been plugins for edit suites that let you specify the grain and color process of specific film stocks to get the look you want.

People today miss the point that things like grain can be an intentional directorial choice and not an artifact to be removed.

Now-a-days, I agree, grain is more of an aesthetic choice and for modern films. And, in fact, I generally don't enable de-noise when it's fairly clear that's what's happening.

However, for a lot of film shot pre-2010, grain is an artifact that's not there by choice or artistically. Other than perhaps the film 300.

It just so happens that most of my personal media fits in that box of being pre-2010 which is why I generally denoise.

Something like 30 rock, or The Office, for example, don't have film grain because of some artistic choice.

Interestingly, though, "That 70s' show" does in a few cases even though it's somewhat noisy be default. That's a more tough call.

Even before 2010, directors and their cinematographers put a lot of thought into what film stock to use in order to build the aesthetic they want for their film. Grain characteristics are one of the most prominent distinctions among different stocks.

Again, depends on what's being shot. Like I said, 300 is a good pre-2010 example of a film stock/grain specifically chosen for it's artistic value.

However, for a bunch of film and especially tv shows, the choice had FAR less to do with aesthetics and was more related to cost. Big budget films certainly could pick any sort of equipment/stock they wanted. Lower budget productions didn't necessarily have that luxury.

I'm not saying it didn't happen, rather that the choice in stock was more often than not "cheap while being as clear as we can afford".

Again, you see this with modern film where grain is almost never added (except for specific scenes trying to give more of a dated effect). That, to me, says cinematographers aren't generally trying to pick their stock to add grain. Some do, but that's the exception and not the rule.

Storage is, but additional bandwidth is seldom spent on quality. It's more often spent on cramming in more bullshit, AKA another home-shopping channel.

In the olden days when cable and satellite were still relevant, sure.

Today, Netflix doesn't need to use less bandwidth just to make room for Hobomax and Paramount+.

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