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AV1@Scale: Film Grain Synthesis, The Awakening

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Re: AV1@Scale: Film Grain Synthesis, The Awakening

#41

Post by zerocrates »

ConanRus wrote: post #31

Everything is fake now. I want a technology which works with a raw film scans, not even compressing them to JPEG, which is a 1st step in loosing the details BTW. Motion detection, key frames, delta frames - fine. But with a lossless video. On a Blu Ray off course, i don't care much about streaming.

I wonder how much you'd get with such a technology... truly uncompressed 4K video you're talking about something on the order of a few terabytes for a 90-minute movie, so way way bigger than the biggest 4K Blu-ray discs. Lossless compression would get you under that number, but far enough to matter?

Re: AV1@Scale: Film Grain Synthesis, The Awakening

#42

Post by NoMoreNicksLeft »

rainworld wrote: post #22
fidotron wrote: post #3

There are definite philosophical questions over the merits of adding noise, but the problem with their example here is their denoising process appears to excessively blur everything, so both it and the synthesized grain image look noticeably less sharp than the source. The grain itself also looks too much like basic noise, and not really grain like.

These days, when we see noise/grain in an end product it has likely been added in post-production. So, ideally, studios would provide distributors with a noiseless source plus grain synthesis parameters. Bonus: many viewers would welcome an option to turn it off.

I'll keep the film grain, I just want to be able to turn off laugh tracks.

Re: AV1@Scale: Film Grain Synthesis, The Awakening

#43

Post by CharlesW »

ConanRus wrote: post #31

Everything is fake now. I want a technology which works with a raw film scans, not even compressing them to JPEG, which is a 1st step in loosing the details BTW. Motion detection, key frames, delta frames - fine. But with a lossless video. On a Blu Ray off course, i don't care much about streaming.

A 4K/24p film encoded with Apple ProRes 4444 XQ (not even ProRes RAW) is 716 GB per hour, so you would need to swap a total of 30 Blu-ray discs once every 4 minutes in order to watch a 2 hour movie.

Re: AV1@Scale: Film Grain Synthesis, The Awakening

#44

Post by eviks »

messe wrote: post #24
eviks wrote: post #21

> Picture this: you’re watching a classic film, and the subtle dance of film grain adds a layer of authenticity and nostalgia to every scene It just adds visual noise that obscures details of the authentic scene, and nothing prevents nostalgia from being tied to many of the more prominent visual cues like old actors or your own old memories from when you watched it first... > contributing to [film's] realism But ther…

> It just adds visual noise that obscures details of the authentic scene Does it add any more than modern video compression techniques? What constitutes noise in cinema, is somewhat subjective.

Which modern compression artifacts that are still visible at high bitrates do you have in mind that would similarly detail-obscuring?

Re: AV1@Scale: Film Grain Synthesis, The Awakening

#45

Post by throw0101d »

Kina wrote: post #18
jedbrooke wrote: post #2

> This grain, formed from tiny particles during the film’s development, is more than just a visual effect. It plays a key role in storytelling by enhancing the film’s depth and contributing to its realism. I never understood the “grain = realism” thing. my real eyes don’t have grain. I do appreciate the role of grain as an artistic tool though, so this is still cool tech

This reminds me of modern windows having fake panes. They’re just strips that are applied to give the impressions that there are multiple smaller panes because people are used to that and it feels “correct”. I have to imagine past glassmakers would have been absolutely enthralled by the ability we now have to make uniform, large sheets of glass, but here we are emulating the compromises they had to make because we ar…

> They’re just strips that are applied to give the impressions that there are multiple smaller panes because people are used to that and it feels “correct”.

It is more than just 'feeling correct': windows and their various (sub-)elements that make them up (can) change the architectural proportions and how the building is perceived as a whole:

* https://www.youtube.com/watch?v=uAMyUoDz4Og

* https://www.youtube.com/watch?v=_c8Ahs9Tcnc&t=49

It is similar with columns: they're not just 'tall-and-narrow', but rather have certain proportions and shapes depending on the style and aesthetic/feeling one wishes to convey:

* https://en.wikipedia.org/wiki/Classical_order

And these proportions can even be 'fractal': the window panes related to windows as a whole, related to the building as a whole:

* https://www.youtube.com/watch?v=J-0XJpPnlrA&t=3m13s

* https://en.wikipedia.org/wiki/Golden_rectangle

* https://en.wikipedia.org/wiki/List_of_works_designed_with_th...

* https://www.nngroup.com/articles/golden-ratio-ui-design/

Re: AV1@Scale: Film Grain Synthesis, The Awakening

#46

Post by kibwen »

eviks wrote: post #21

> Picture this: you’re watching a classic film, and the subtle dance of film grain adds a layer of authenticity and nostalgia to every scene It just adds visual noise that obscures details of the authentic scene, and nothing prevents nostalgia from being tied to many of the more prominent visual cues like old actors or your own old memories from when you watched it first... > contributing to [film's] realism But ther…

Documentaries might care about accurately representing reality. For every other cinematic genre, "authenticity" is not an inherent goal. If film grain is part of the director's vision, then that's just as valid as a choice to have dramatic non-diagetic music playing in the background of a scene (which is highly inauthentic, but also highly effective at evoking emotion, which is the point of art).

Re: AV1@Scale: Film Grain Synthesis, The Awakening

#47

Post by kderbe »

jedbrooke wrote: post #2

> This grain, formed from tiny particles during the film’s development, is more than just a visual effect. It plays a key role in storytelling by enhancing the film’s depth and contributing to its realism. I never understood the “grain = realism” thing. my real eyes don’t have grain. I do appreciate the role of grain as an artistic tool though, so this is still cool tech

The article points out the masking effect of grain, which hides the fake-looking compression artifacts, and also the familiarity/nostalgia aspect. But I will offer an additional explanation.

Look around you: nearly all surfaces have some kind of fine texture and are not visually uniform. When this is recorded as video, the fine texture is diminished due to things like camera optics, limited resolution, and compression smoothing. Film grain supplies some of the high frequency visual stimulus that was lost.

Our eyes and brains like that high frequency stimulation and aren't choosy about whether the exact noise pattern from the original scene is reproduced. That's why the x265 video encoder (which doesn't have grain synthesis since it produces H.265 video) has a psy-rd parameter that basically says, "try to keep the compressed video as 'energetic' as the original, even if the energy isn't in the exact same spot", and even a psy-rdoq parameter that says, "prefer higher 'energy' in general". These parameters can be adjusted to make a compressed video look better without needing to store more data.

Re: AV1@Scale: Film Grain Synthesis, The Awakening

#48

Post by bee_rider »

dperfect wrote: post #25
fidotron wrote: post #3

There are definite philosophical questions over the merits of adding noise, but the problem with their example here is their denoising process appears to excessively blur everything, so both it and the synthesized grain image look noticeably less sharp than the source. The grain itself also looks too much like basic noise, and not really grain like.

> both it and the synthesized grain image look noticeably less sharp than the source That's true, but at a given bitrate (until you get to very high bitrates), the compressed original will usually look worse and less sharp because so many bits are spent trying to encode the original grain. As a result, that original grain tends to get "smeared" over larger areas, making it look muddy. You lose sharpness in areas of t…

It seems like a shame that they didn’t include a screenshot of the original (with natural grain), after suffering from low-bitrate streaming. Aka the actual baseline.

I can see why they want to compare against the actual local copy of the video with the natural grain. But that’s the perfect copy that they can’t actually hope to match.

Re: AV1@Scale: Film Grain Synthesis, The Awakening

#49

Post by CharlesW »

ChrisArchitect wrote: post #20

How much grain is there in IMAX films? There's an influx of high-profile directors/films right now and in pipeline filmed for IMAX (F1: The Movie I think, Mission Impossible, etc) and Christopher Nolan's Odyssey coming next year shot entirely on IMAX film with newly developed smaller/quieter cameras made to accomplish it.

> How much grain is there in IMAX films?

I've read that a 15-perf 65mm IMAX negative shot with slower film stocks is "virtually grainless", even when viewed on a 70ft screen. Grain is apparently noticeable in IMAX films when large/fast stocks are used and pushed toward their limits, and (of course) when smaller-format film stocks have been blown up.

Re: AV1@Scale: Film Grain Synthesis, The Awakening

#50

Post by dperfect »

To the comments hating on grain: everything naturally has some amount of noise or grain - even the best digital sensors. Heck, even your eyes do. It's useful beyond just aesthetics. It tends to increase perceived sharpness and hides flaws like color banding and compression artifacts.

That's not to say that all noise and grain is good. It can be unavoidable, due to inferior technology, or a result of poor creative choices. It can even be distracting. But the alternative where everything undergoes denoising (which many of our cameras do by default now) is much worse in my opinion. To my eyes, the smoothing that happens with denoising often looks unrealistic and far more distracting.

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