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AV1@Scale: Film Grain Synthesis, The Awakening

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

#21

Post by eviks »

> 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 there is no grain in reality, so it does the opposite

Otherwise I'm glad AV1 marches along and instead of wasting bitrate encoding visual garbage has an algorithmic replacement mechanism- which also means you could turn it off easier.

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

#22

Post by rainworld »

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.

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

#23

Post by postalrat »

jrm4 wrote: post #5

Yup, yet another example of the thing I'll never stop finding fascinating: ANY noticeable percieved "flaw" in any creative media will eventually become an aesthetic choice.

I think there is a bit more to it. For example when developing a game when CRTs were popular they were using CRTs to view their game and making decisions based on what they saw on the CRT. If you display the same game with perfect square pixels it looks different. If the developers were viewing square pixels when developing the game they would make different decisions.

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

#24

Post by messe »

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.

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

#25

Post by dperfect »

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 the actual scene because it's trying (and often failing) to encode sharp grains.

Film Grain Synthesis makes sense for streaming where bandwidth is limited, but I'll agree that in the examples, the synthesized grain doesn't look very grain-like. And, depending on the amount and method of denoising, it can definitely blur details from the scene.

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

#28

Post by meatmanek »

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…

> But there is no grain in reality, so it does the opposite

Well ackchually -- illumination is inherently random, so all time-bounded captures of a scene (including what your eyes do) are subject to shot noise: https://en.wikipedia.org/wiki/Shot_noise

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

#29

Post by hypertexthero »

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.

A film that explores this is Antonioni’s Blowup: https://en.wikipedia.org/wiki/Blowup

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

#30

Post by haiku2077 »

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

My vision is grainy because of visual snow. Which is why I turn off film grain in games, it stacks on my vision and makes a visual mess.
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